United States Patent (19) 11) 4,265,809 Holsopple et al. 45 May 5, 1981

54 METHOD OF MAKING EPOXIDE-LIGNIN 3,519,581 7/1970 Moorer et al...... 260/124 RESNS 3,577,358 5/1971 Santelli et al 260/124 3,578,651 5/1971 Ludwig ...... 260/24 76 Inventors: Dale B. Holsopple, 12908 Thraves 4,07,474 4/1977 Glasser et al...... 260/24 Rd., Garfield Heights, Ohio 44125; 4,045,421 8/1977 Wenzel et al...... 260/124 Wasyl W. Kurple, 110 W. Grace 4,111,928 9/1978 Holsopple et al...... 260/124 Ave., Bedford, Ohio 44146; William M. Kurple, 16607 N. 34th Ave., OTHER PUBLICATIONS Phoenix, Ariz. 85023; Kenneth R. A.B.I.P.C., vol. 45, No. 9 (Mar. 1975) 9519. Kurple, 9533 Springborn Rd., A.B.I.P.C., vol. 46, No. 2 (Aug. 1975) 1653. Anchorville, Mich. 48004 A.B.I.P.C., vol. 46, No. 11 (May 1976) 11492. 21 Appl. No.: 72,244 A.B.I.P.C., vol. 46, No. 5 (Nov. 1975) 4636. A.B.I.P.C., vol. 45, No. 1 (Jul. 1974) 501. 22 Filed: Sep. 4, 1979 A.B.I.P.C., vol. 46, No. 8 (Feb. 1976) 8218. 51) Int. Cl...... C07G1/00; C08L97/00 Primary Examiner-Delbert R. Phillips 52 U.S. C...... 260/124 R; 260/17.5 58) Field of Search ...... 260/124 57 ABSTRACT (56) References Cited A process for making lignin-epoxide resins from lignin separated from the waste cooking liquor from a paper U.S. PATENT DOCUMENTS pulping process comprising the steps of reacting the 2,168,160 8/1939 Hochwalt et al...... 260/24 separated lignin with a chemical system to produce 2,816,100 12/1957 Walker ...... 260/124 3,251,820 5/1966 Grangoard ...... 260/24 unsaturated end groups on the lignin molecule which 3,296,159 1/1967 Lissner ...... 260/124 are epoxidized to produce the resin. 3,447,939 6/1969 Johnson ...... 260/124 3,492,228 1/1970 Kim ...... 260/124 24 Claims, 1 Drawing Figure U.S. Patent May 5, 1981 4,265,809

S EPA RATION OF GNN FROM

BLACK L Q UOR

REACTION OF LIGN IN TO PRODUCE UNSATURATED END GROUPS ON

LGN N MOLE CULE

F. G.

E POX DATION

PLASTCs ADHES WES PANTS 4,265,809 1. 2 The lignin separation portion of the present invention METHOD OF MAKING EPOXDE-LIGNIN is highly useful in and of itself since it provides an eco RESNS nomical method for acquiring an excellent grade of lignin from both kraft and sulfite black liquor. This invention relates to the separation of lignin from 5 The present prior art teaches that lignin in kraft black waste black cooking liquor resulting from the kraft and liquor may be precipitated and then filtered. Because of sulfite paper pulping process and the preparation of the fine colloidal nature of precipitated lignin the filtra useful organic materials from the lignin. The useful tion of lignin becomes a difficult procedure. Because of organic materials include plastics, adhesives and resins this procedure lignin is fused during processing and the for use, for example, in paints. 10 liqnin formed is a frit-like material. Unfortunately this The kraft process broadly relates to the separation of frit-like lignin material is very difficult to dissolve in wood into cellulose and lignin. Other materials are solvents and other organic media. These frit-like lignins separated, for example sugars, hemicelluloses, tall oil, can be reprocessed to make them more usable, but the and other chemicals. The separation is effected essen extra processing makes the cost of the lignin too expen tially by cutting the wood into small portions and then 15 sive for large market application. cooking them under heat and pressure with certain The present invention enables lignin to be obtained pulping chemicals which include sodium hydroxide and from kraft black liquor in a fine powder or dissolved in sodium sulfide. This cooking renders the lignin, sugars an organic medium which then can be readily dissolved and hemicellulose materials soluble and these form the in various solvents and organic media. This solubility major materials present in the waste black liquor. There 20 characteristic enables the lignin produced from the are, of course, other chemicals present as well as dis invention to be utilized in large market applications. solved pulping chemicals. Normal procedure in a kraft One significant advantage of the invention is that poly plant is to evaporate the black liquor to a given solids ols can be used as the solvent or organic medium for the content which solids are then burned in a furnace to separation of lignin from kraft black liquor or sulfite - recover the inorganic pulping chemicals which are 25 waste liquor. In this way lignin can be effectively uti recycled to produce more pulp. The cellulose is insolu lized in many polyurethane applications, because by ble in the black liquor and is separated therefrom and using the lignin in conjunction with the polyol, the cost is made into paper. The only value obtained from the of the polyurethane product is significantly reduced. lignin in this justmentioned procedure is the heat value In this invention relating to the separation of lignin derived in the furnace. The sulfite process is well 30 from black liquor there are three distinct aspects, one known to those skilled in the art. aspect is where the lignin is soluble in the solvent or The present invention basically involves the separa organic chemical medium that is used in the separation. tion or extraction of lignin from waste black pulping As the solubility of the lignin in the aqueous phase is liquor. The lignin may be used for many purposes and reduced, the lignin has more affinity for the solvent one use is to chemically place reactive unsaturated car 35 phase than the aqueous phase and a separation results. bonyl groups or unsaturated nitrogen-containing com In this situation the preferred procedure is to reduce the pounds on the lignin molecule in addition to the unsatu solubility of the lignin in the aqueous phase. The reduc rated groups already naturally existing on the lignin tion of the solubility of the lignin in the aqueous phase molecule and thereafter produce an epoxide-lignin resin may not be necessary if the lignin is significantly soluble by reaction with another chemical, for example hydro in the solvent or organic chemical medium. The de gen peroxide. The epoxide-lignin resin may be cured to scription of this technology is demonstrated in examples a hard infusible plastic by means of heat and/or a cata 1 through 25 of the specification. lyst, it may be reacted with various fatty acids to pro In the second approach of the separation invention, duce resins for paints and inks or it may be reacted with the lignin has normally only partial solubility in the various amines to produce polyamines or polyamides 45 solvent or organic chemical medium. In this case, as the for use as adhesives or plastics. The aqueous phase of solubility of lignin in the aqueous phase is descreased, the waste black liquor from which the lignin is sepa the lignin, because of its partial solubility in the solvent rated may be recycled in the normal way to recover the or organic chemical medium, has more affinity for the pulping chemicals. solvent phase than the aqueous phase and a separation The present invention provides a new and inexpen 50 results. The description of this technology is demon sive source of epoxide resins and the ultimate products strated in examples 68 through 74 of the specification. therefrom, at a time when the national petroleum sup In the third approach of the invention, the lignin is ply is being acutely diminished. The supply of lignin considered to have no solubility in the solvent or chemi from the paper industry measures in the millions of tons cal medium. In this case, as the solubility of the lignin is annually and as mentioned above, the bulk of this lignin 55 decreased in the aqueous phase, the lignin becomes is used for its heat value which is acquired by burning. dispersed in the solvent or chemical medium. This dis The lignin source is essentially renewed each year by persion of the lignin can be improved through mechani the tree planting policies of the major paper companies. cal means. The dispersion of the lignin is achieved even Some of the strongest adhesives and plastics with excel though the lignin is not soluble in the solvent or chemi lent mechanical properties are epoxy-type adhesives cal medium, by the fact that the surface of the lignin and epoxy-type plastics. particles is wetted by the solvent or chemical medium. Even though there are on the order of 160 million Once the lignin particle is wetted, the lignin particles pounds of epoxy, resins being used annually in the are prevented from forming aggregates. Thus the lignin United States, the largest volume markets have been is suspended in the solvent or chemical medium. The virtually untouched because of the present high cost of 65 wetting of the lignin particles is enhanced by such me these resins. The present invention will drastically re chanical means as agitation and conventional dispersing duce the cost of epoxy-type resins so they can economi equipment. These lignin particles are formed when the cally compete for the yet untouched markets. I solubility of the lignin in the aqueous phase is decreased 4,265,809 3 4. to the point where the lignin is no longer soluble and the end of four hours there is alignin-solvent layer on precipitates out. Another significant advantage of the top which produces 908 gms, of lignin. invention is that of using fluorocarbons which are "Freon' type of materials for the separation of lignin EXAMPLE 2 from kraft black liquor and sulfite waste liquor. These 5 This example illustrates the extraction of lignin from fluorocarbons are low boiling point materials which kraft black liquor into an organic solvent, and the use of means that significantly less energy is required to spray an ion (magnesium sulfate) to reduce soap formation dry the lignin from these materials. Also these fluoro and thus improve the extraction. carbons are nonflammable which means that safety is PROCEDURE: Charge 4000 ml. (4 parts) of kraft black also significantly improved. These materials are also 10 liquor (50% solids) into a 5-gallon vessel. Then add relatively non-toxic which also improves safety. The 1400 ml. (1.4 parts) of water and stir. Then add 1400 fluorocarbons are also inert so they can easily be recov ml. (1.4 parts) of mesityl oxide and stir. Premix 40 ered after spray drying and used again. The description gms. (0.04 part) of magnesium sulfate in 200 ml. (0.2 of this technology is demonstrated in examples 75 part) water under agitation over 10 minutes. Add 450 through 79 of the specification. 15 ml. (0.45 part) of 80% acetic acid slowly while agitat The lignin from sulfite waste liquor is presently ob ing the mixture. This addition requires about 15 min tained by spray drying the waste sulfite liquor. The final utes. Stir for 10 minutes and stop the agitation and product contains lignin, and also wood sugars, hemicel allow the mixture to stand. At the end of four hours luloses and water soluble inorganic salts. These water there is alignin-solvent layer formed which produces soluble materials severely limit the potential applica 20 950 gms. of lignin. tions that lignin from sulfite waste find. This invention is also applicable to sulfite waste liquor and this technol EXAMPLE 3 ogy is demonstrated in examples 80 through 85 of the This example illustrates the extraction of lignin from specification. kraft black liquor which contains 20% solids. Other objects and a fuller understanding of this in 25 PROCEDURE: Charge 8000 ml. (8 parts) of kraft li vention may be had by referring to the following de quor into a 5-gallon vessel. Then add 2400 ml. (24 scription and claims, taken in conjunction with the ac parts) of water and stir. Then add 5000 gms. (5 parts) companying drawings, in which: of mesityl oxide and stir. Then add 600 ml. (0.6 part) FIG. 1 is a flow sheet showing the various steps in 30 of 80% acetic acid over a 15-minute interval while volved in the teachings of the present invention. the mixture is under agitation. Then stir for another As seen in the flow sheet of FIG. 1 and as discussed 15 minutes. The agitation is stopped and the mixture above, the first procedure involved in the present inven allowed to stand for the fomation of a lignin-solvent tion is the separation or extraction of the lignin from the layer. waste black liquor resulting from the kraft paper pulp This layer produces 700 gms. of lignin. ing process. The first twenty-five examples (numbered 35 Examples 1 through 25) illustrate this separation by the EXAMPLE 4 use of ketones, esters, aldehydes and ethers. Solids con This example illustrates the extraction of lignin from tent of the black illustrated is 20% and 50%; however, kraft black liquor which contains 20% solids. other solids content may be utilized. The examples also PROCEDURE: Charge 4000 ml. (4 parts) black liquor illustrate that the separation may take place in acid or (20% solids) into a 5-gallon vessel with some means basic media. The specific ketones demonstrated are of agitation. Then charge 2000 ml. (2 parts) of water mesityl oxide, cyclohexanone, isophorone, and methy and stir. Then add 1400 ml. (1.4 parts) of mesityl ... heptyl ketone; esters are 2, 2 butoxyethoxyethyl ace oxide and stir. Then slowly add 375 ml. (0.375 part) of tate, hexyl acetate, heptyl acetate, amyl acetate, iso 45 80% acetic acid over a 15-minute interval. The mix amyl acetate and phenyl acetate; aldehydes are benzal ture is then stirred for an additional 15 minutes and dehyde, valeradehyde, butyraldehyde and furfural; and allowed to stand with no agitation. A lignin-solvent ethers may be butyl ether and 2, 2 butoxyethoxyethyl layer starts to form and is complete within a few acetate in addition to being an ester, is also an ether. hours. This layer produces approximately 350gms. of EXAMPLE 1. 50 lignin. This example illustrates the extraction of lignin from EXAMPLE 5 kraft black liquor into an organic solvent. The pH of the The example illustrates the extraction of lignin from black liquor may be on the order of 12 or 13. kraft black liquor which contains 20% solids with an PROCEDURE: Charge 4000 ml. (4 parts) kraft black 55 organic solvent. liquor (50% solids) into a 5-gallon vessel with some PROCEDURE: Charge 4000 ml. (4 parts) of kraft black means of agitation. Then added 1000 ml. of water (1 liquor into a 5-gallon vessel provided with some part) and stir. Then add 700 ml. (0.7 part) of mesityl means of agitation. Then add 1000 ml. (1 part) water oxide (solvent) and stir. While the mixture is being and stir. To this mixture is then added 2000 ml. (2 stirred, add 250 ml. (0.25 part) of 80% acetic acid 60 parts) of mesityl oxide and stirred for 5 minutes. Then slowly over 10 minutes and stir for another 10 min 350 ml. (0.35 part) of 80% acetic acid is added slowly utes. The mixture starts to thicken and then thins out over a 15-minute interval, until the mixture is acidic. again. At this time add another 300 ml. (0.3 part) of The addition of acid is stopped if the mixture starts to 80% acetic acid until the mixture is acidic. The foam due to the evolution of gases. The mixture is amount of acid required may vary because alkalinity 65 stirred for 15 minutes and the agitation stopped. of the kraft pulps may also vary. The mixture is When the mixture is acidic, it normally will have a stirred for 10 minutes and the agitation is then light brown color. The lignin-solvent layer which stopped. The mixture is then allowed to stand and at separates produces approximately 350 gms. of lignin. 4,265,809 5 6 is continued until the mixture is acidic (pH of less EXAMPLE 6 than 7.0). The rate is maintained so that no frothing This example illustrates the separation of lignin from occurs while the mixture is under agitation. After the kraft black liquor by using a solvent such as methylene mixture is acidic the carbon dioxide gas is discontin chloride which is a chlorinated hydrocarbon. ued and the mixture stirred for an additional 15 min PROCEDURE: Charge 400 ml. (4 parts) of kraft black utes. The agitation is stopped and the mixture cov liquor (50% solids) into a one liter vessel. Add 100 ered. The solvent-lignin layer produces 711 gms. of ml. (1 part) of water and stir. Then add 100 ml. (1 lignin. part) of methylene chloride. While this mixture is being stirred, add 25 ml. (0.25 parts) of 80% acetic 10 EXAMPLE 10 acid slowly over a five minute interval. As soon as the This example illustrates the extraction of lignin from viscosity of the mixture starts to increase the stirring kraft black liquor into an organic solvent by reducing may be discontinued and a layer starts to form which the alkalinity but still maintaining a basic solution, with contains the lignin. carbon dioxide gas. The pH of the solution in Examples 1 through 6 is 15 PROCEDURE: Charge 4000 ml. (4 parts) kraft black normally kept between 4.5 and 6.5. These separations liquor (50% solids) into a 5-gallon vessel equipped were all carried out at about room temperature or with some means of agitation. Then add 400 ml. (4 slightly lower. parts) water and stir. Next add 2000 ml. (2 parts) of EXAMPLE 7 mesityl oxide and stir for 5 minutes. While the mix 20 ture is under agitation, carbon dioxide gas is passed This example illustrates the extraction of lignin from through a glass frit or bubbler which is immersed at kraft black liquor into an organic solvent by reducing the bottom of the 5-gallon vessel. The rate is adjusted the pH but still maintaining a basic solution. so that no frothing occurs while the mixture is being PROCEDURE: Charge 4000 ml. kraft black liquor agitated. When the pH of the mixture is in the range (50% solids) into a 5-gallon vessel with some means 25 7 to 8.9 pH units, the carbon dioxide gas may be of agitation. Then add 400 ml. (4 parts) of water and discontinued, however, the closer to an acid pH the stir. Then add 1400 ml. (1.4 parts) of mesityl oxide better the yields will be. After the carbon dioxide gas and stir for 5 minutes. While the mixture is being is discontinued, the mixture is stirred for an additional stirred, 300 ml. (0.3 part) of 80% acetic acid is added 15 minutes. The agitation is then stopped and the slowly over 15 minutes until the pH of the mixture is 30 vessel covered. The lignin layer produces 665gms. of still alkaline, between about 7.5 and 8.5. The mixture lignin. is then stirred for an additional 15 minutes, and the agitation stopped and the vessel covered. A lignin EXAMPLE 11 containing layer separates which contains about 670 This example illustrates the extraction of lignin from gms. of lignin. 35 kraft black liquor into an organic solvent by reducing the alkalinity of the black liquor with a mineral acid but EXAMPLE 8 still maintaining a pH of 7 or greater. p0 PROCE This example illustrates the extraction of lignin from DURE: Charge 4000 ml. (4 parts) of kraft black liquor kraft black liquor into an organic solvent by acidifying (50% solids) into a 5-gallon vessel equipped with some with a mineral acid. means of agitation. Then add 4000 ml. (4 parts) of water PROCEDURE: Charge 4000 ml. (4 parts) of kraft black and stir. Next add 2000 ml. (2 parts) of mesityl oxide and liquor (50% solids) into a 5-gallon vessel equipped stir for 5 minutes. Premix 100 ml. (0.1 part) of concen with some means of agitation. Then add 4000 ml. (4 trated sulfuric acid into 1000 ml. (1 part) of water. This parts) of water and stir. Then add 2000 ml. (2 parts) of sulfuric acid solution is then added slowly to the mix mesityl oxide and stir for 5 minutes. Premix 150 ml. 45 ture under agitation over a 15-minute period. The (0.15 part) of concentrated sulfuric acid into 1000 ml. amount of acid needed will vary, because of the varying (1 part) of water. Then add this sulfuric acid solution amounts of base present in kraft pulps. Therefore, the slowly over 15 minutes while the mixture is under addition of acid is stopped when the desired pH is agitation. When the color of the mixture becomes a reached. In this example a pH of 7.5 to 8.0 was suffi light brown the mixture is then acidic and the addi 50 cient. After the acid has been added, the mixture is tion of acid is stopped when the pH is in the range of stirred for an additional 15 minutes. Then the agitation 5 to 6.5 pH units. The agitation is continued for an is stopped and the vessel covered. The lignin layer additional 15 minutes and then stopped. The 5-gallon produces 710 gms. of lignin. vessel is then covered. The lignin layer contains 813 gms. of lignin. 55 EXAMPLE 12 This example illustrates the extraction of lignin from EXAMPLE 9 kraft black liquor into the organic solvent methylheptyl This example illustrates the extraction of lignin from ketone by acidifying the solution. kraft black liquor into an organic solvent by acidifying PROCEDURE: Charge 4000 ml. (4 parts) of kraft black with a gas that produces an acid in an aqueous solution. 60 liquor (50% solids) into a 5-gallon vessel equipped PROCEDURE: Charge 4000 ml. (4 parts) kraft black with some means of agitation. Then add 2000 ml. (2 liquor (50% solids) into a 5-gallon vessel equipped parts) of water and stir. Next add 4000 ml. (4 parts) of with some means of agitation. Then add 4000 ml. (4 methyl heptyl ketone and stir for 5 minutes. Then parts) of water and stir. Then add 2000 ml. (2 parts) of slowly add 550 ml. (0.55 part) of 80% acetic acid over mesityl oxide and stir for 5 minutes. While the mix 65 a 15-minute interval while the mixture is being ture is under agitation, carbon dioxide gas is passed stirred. When the mixture is acidic (pH 5.5 to 6.0) the through a glass frit or bubbler immersed near the addition of acid is discontinued and the mixture bottom of the mixture. The use of carbon dioxide gas stirred for an additional 15 minutes. When the agita 4,265,809 7 8 tion has stopped, the vessel is covered. The lignin layer produces 578 gms. of lignin. EXAMPLE 16 This example illustrates the separation of lignin from EXAMPLE 13 kraft black liquor by using mesityl oxide with a mixture This example illustrates the extraction of lignin into 5 of xylenes while reducing the alkalinity of the solution the organic solvent 2, 2, butoxy, ethoxy, ethyl acetate, but still maintaining a basic pH. from kraft black liquor. PROCEDURE: Charge 8000 ml. (8 parts) of kraft black PROCEDURE: Charge 4000 ml. (4 parts) of kraft black liquor (50% solids) into a 5-gallon vessel equipped liquor (50% solids) into a 5-gallon vessel equipped with some means of agitation. Then add 4000 ml. (4 with some means of agitation. Then add 4000 ml. (4 O parts) of water and stir. Then premix 200 ml. (0.2 parts) of water and stir. Next add 4000 ml. (4 parts) of part) of mesityl oxide with 1000 ml. (1 part) of a 2, 2, butoxy, ethoxy, ethyl acetate and stir for 5 min xylene solvent which consists of a mixture of ortho utes. Then slowly add 550 ml. (0.55 part) of 80% and para xylene as well as some ethyl benzene. This acetic acid over a 15-minute interval while the mix premix is then added to the black liquor solution and ture is being agitated. Once the mixture is acidic (pH 15 stirred for 5 minutes. While the mixture is being 5.5 to 6) the addition of acid is discontinued and the stirred 500 ml. (0.5 part) of 80% acetic acid is added mixture is stirred for an additional 15 minutes. After slowly over 5 minutes. The viscosity of the mixture the agitation has stopped, the vessel is then covered starts to thicken and then thins out again. At this time and a layer will start to form. The lignin layer pro another 100 ml. (0.1 part) of 80% acetic acid is added until the pH of the mixture is in the preferred range of duces 435 gms. of lignin. 7.8 to 8.2. The mixture is then stirred for another 5 EXAMPLE 1.4 minutes, and then the agitation stopped. The mixture This example illustrates the extraction or separation is then allowed to stand and at the end of one-half of lignin from kraft black liquor into the organic solvent hour a layer has formed which contains 1950 gms. of benzaldehyde. 25 lignin. PROCEDURE: Charge 4000 ml. (4 parts) of kraft black EXAMPLE 7 liquor (50% solids) into a 5-gallon vessel equipped This example illustrates the extraction or separation with some means of agitation. Then add 1000 ml. (1 of lignin from kraft black liquor (50% solids) with cy part) of water and stir. Next add 5000 ml. (5 parts) of 30 clohexanone, an organic ketone. benzaldehyde and stir for 5 minutes. Then slowly add PROCEDURE: Charge 4000 ml. (4 parts) of kraft black 550 ml. (0.55 part) of 80% acetic acid over a 15 liquor into a 5-gallon vessel provided with some minute interval until the mixture is weakly acidic (pH means of agitation. Then add 1000 ml. (1 part) water 5.5 to 6). Then the addition of acid is discontinued and stir. To this mixture is then added 2000 ml. (2 and the mixture stirred for an additional 10 minutes. 35 parts) of cyclohexanone and stirred for 5 minutes. After the agitation has stopped, the vessel is then Then 350 ml. (0.35 part) of 80% acetic acid is added covered. Because of the density of benzaldehyde, the slowly over a 15-minute interval, until the mixture is layer containing lignin may not rise to the top, since acidic. The addition of acid is stopped if the mixture the density of the benzaldehyde lignin layer may be starts to foam due to the evolution of gases. The greater than the density of the aqueous mixture. The mixture is stirred for 5 minutes and the agitation lignin layer produces 756 gms. of lignin. stopped. When the mixture is acidic, it normally will have a light brown color. The lignin layer which EXAMPLE 1.5 separates produces 805 gms. of lignin. This example illustrates the extraction of lignin from kraft black liquor into a combination of organic sol 45 EXAMPLE 8 vents, such as xylenes and furfural. In order to achieve This example illustrates the separation or extraction the optimum extraction or separation, it may be advan of lignin from kraft black liquor (50% solids) with iso tageous to combine various solvents to obtain improved phorone, an organic ketone. results. PROCEDURE: Charge 4000 ml. (4 parts) of kraft black PROCEDURE: Charge 4000 ml. (4 parts) of kraft black 50 liquor into a 5-gallon vessel provided with some liquor (50% solids) into a 5-gallon vessel. Then add means of agitation. Then add 1000 ml. (1 part) water 2000 ml. (2 parts) of water and stir. Premix 2000 ml. and stir. To this mixture is then added 2000 ml. (2 (2 parts) of furfural and 2000 ml. (2 parts) of xylene parts) of isophorone and stirred for 5 minutes. Then and then add this premix and stir for 10 minutes. Next 350 ml. (0.35 part) of 80% acetic acid is added slowly slowly add 550 ml. (0.55 part) of 80% acetic acid to 55 over a 15-minute interval, until the mixture is acidic. the mixture over a 15-minute interval. Once the mix The addition of acid is stopped if the mixture starts to ture has become acidic (preferably in the pH range foam due to the evolution of gases. The mixture is 5.0 to 6.5), the addition of acid is stopped and the stirred for 15 minutes and the agitation stopped. mixture is stirred for an additional 15 minutes. Then When the mixture is acidic, it normally will have a agitation is stopped and the vessel covered. The for 60 light brown color. The lignin layer which separates mation of a layer will be complete in 4 to 5 hours. The produces 910 gms. of lignin. lignin layer produces 465 gms. of lignin. The xylene in this example acts as a carrier or extender for the EXAMPLE 19 furfural and improves the extraction economics. The This example illustrates the extraction of lignin from Xylene used was a commercial grade which contained 65 kraft lignin black liquor (50% solids) with valeraide m-xylene, o-xylene, p-xylene and ethyl benzene. Tol hyde, an organic aldehyde. uene and benzene might also be used as a carrier or PROCEDURE: Charge 4000 ml. (4 parts) of kraft black extender. liquor into a 5-gallon vessel provided with some 4,265,809 9 10 means of agitation. Then add 1000 ml. (1 part) water and stir. To this mixture is then added 2000 ml. (2 EXAMPLE 23 parts) of valeraldehyde and stirred for 5 minutes. This example illustrates the separation or extraction Then 350 ml. (0.35 part) of 80% acetic acid is added of lignin from kraft black liquor (50% solids) with hep 5 tyl acetate, an organic ester. slowly over a 15-minute interval, until the mixture is PROCEDURE: Charge 4000 ml. (4 parts) of kraft black acidic. The addition of acid is stopped if the mixture liquor into a 5-gallon vessel provided with some starts to foam due to the evolution of gases. The means of agitation. Then add 1000 ml. (1 part) water mixture is stirred for 15 minutes and the agitation and stir. To this mixture is then added 2000 ml. (2 stopped. When the mixture is acidic, it normally will 10 parts) of heptyl acetate and stirred for 5 minutes. have a light brown color. The lignin layer which Then 350 ml. (0.35 part) of 80% acetic acid is added separates produces 715 gms. of lignin. slowly over a 15-minute interval until the mixture is EXAMPLE 20 acidic. The addition of acid is stopped if the mixture starts to foam due to the evolution of gases. The This example illustrates the separation or extraction 15 mixture is stirred for 15 minutes and the agitation of lignin from kraft black liquor with butyraldehyde, an stopped. When the mixture is acidic, it normally will organic aldehyde. have a light brown color. The lignin layer which PROCEDURE: Charge 4000 ml. (4 parts) of kraft black separates produces 420 gms. of lignin. liquor into a 5-gallon vessel provided with some means of agitation. Then add 1000 ml. (1 part) water 20 EXAMPLE 24 and stir. To this mixture is then added 2000 ml. (2 This example illustrates the separation or extraction parts) of butyraldehyde and stirred for 5 minutes. of lignin from kraft black liquor (50% solids) with amyl Then 350 ml. (0.35 part) of 80% acetic acid is added acetate, an organic ester. slowly over a 15-minute interval, until the mixture is PROCEDURE: Charge 4000 ml. (4 parts) of kraft black acidic. The addition of acid is stopped if the mixture 25 liquor into a 5-gallon vessel provided with some starts to foam due to the evolution of gases. The means of agitation. Then add 1000 ml. (1 part) water mixture is stirred for 15 minutes and the agitation and stir. To this mixture is then added 2000 ml. (2 stopped. When the mixture is acidic, it normally will parts) of amyl acetate and stirred for 5 minutes. Then have a light brown color. The lignin layer which 350 ml. (0.35 part) of 80% acetic acid is added slowly 30 over a 15-minute interval, until the mixture is acidic. separates produces 435 gms. of lignin. The addition of acid is stopped if the mixture starts to EXAMPLE 21 foam due to the evolution of gases. The mixture is stirred for 15 minutes and the agitation stopped. This example illustrates the separation or extraction When the mixture is acidic, it normally will have a of lignin from kraft black liquor (50% solids) into butyl 35 light brown color. The lignin layer which separates ether, an organic ether. produces 570 gms. of lignin. PROCEDURE: Charge 4000 ml. (4 parts) of kraft black liquor into a 5-gallon vessel provided with some EXAMPLE 25 means of agitation. Then add 1000 ml. (1 part) water This example illustrates the separation or extraction and stir. To this mixture is then added 2000 ml. (2 of lignin from kraft black liquor (50% solids) into iso parts) of butyl ether and stirred for 5 minutes. Then amyl acetate, an organic ester. 350 ml. (0.35 part) of 80% acetic acid is added slowly PROCEDURE: Charge 4000 ml. (4 parts) of kraft black over a 15-minute interval, until the mixture is acidic. liquor into a 5-gallon vessel provided with some The addition of acid is stopped if the mixture starts to means of agitation. Then add 1000 ml. (1 part) water foam due to the evolution of gases. The mixture is 45 and stir. To this mixture is then added 2000 ml. (2 stirred for 15 minutes and the agitation stopped. parts) of iso-amyl acetate and stirred for 5 minutes. When the mixture is acidic, it normally will have a Then 350 ml. (0.35 part) of 80% acetic acid is added light brown color. The lignin layer which separates slowly over a 15-minute interval, until the mixture is produces 565 gms. of lignin. acidic. The addition of acid is stopped if the mixture 50 starts to foam due to the evolution of gases. The EXAMPLE 22 mixture is stirred for 15 minutes and the agitation This example illustrates the separation or extraction stopped. When the mixture is acidic, it normally will oflignin from kraft black liquor (50% solids) with hexyl have a light brown color. The lignin layer which acetate, an organic ester. separates produces 580 gms. of lignin. PROCEDURE: Charge 4000 ml. (4 parts) of kraft black 55 EXAMPLE 26 liquor into a 5-gallon vessel provided with some This example illustrates the separation or extraction means of agitation. Then add 1000 ml. (1 part) water of lignin from kraft black liquor (50% solids) into and stir. To this mixture is then added 2000 ml. (2 phenyl acetate, an organic ester. parts) of hexyl acetate and stirred for 5 minutes. Then 60 PROCEDURE: Charge 4000 ml. (4 parts) of kraft black 350 ml. (0.35 part) of 80% acetic acid is added slowly liquor into a 5-gallon vessel provided with some over a 15-minute interval, until the mixture is acidic. means of agitation. Then add 1000 ml. (1 part) water The addition of acid is stopped if the mixture starts to and stir. To this mixture is then added 2000 ml. (2 foam due to the evolution of gases. The mixture is parts) of phenyl acetate and stirred for 5 minutes. stirred for 15 minutes and the agitation stopped. 65 Then 350 ml. (0.35 part) of 80% acetic acid is added When the mixture is acidic, it normally will have a slowly over a 15-minute interval, until the mixture is light brown color. The lignin layer which separates acidic. The addition of acid is stopped if the mixture produces 407 gms. of lignin. starts to foam due to the evolution of gases. The 4,265,809 12 mixture is stirred for 15 minutes and the agitation PROCEDURE: Charge 1000 gms. (1 part) of the lignin stopped. When the mixture is acidic, it normally will solvent layer from Example 5 into a 5-liter, 3-neck, have a light brown color. The lignin layer which round-bottom flask equipped with a thermometer, separates produces 850 gms. of lignin. dropping funnel and mechanical stirrer. Add 200 ml. The lignin layer containing the solvent and lignin in (0.2 part) of 38% aqueous formaldehyde dropwise the examples above may be utilized in exactly this form over a 10-minute interval, while stirring. Then add or the lignin may be separated from the solvent simply 200 ml. (0.2 part) of deionized water and stir for 5 by drying or spray drying which simply evaporates the minutes and add 30 ml. (0.03 part) of triethylamine solvent under atmospheric or vacuum conditions leav and stir for 30 minutes. The dropping funnel is re ing the lignin in solid form. The following Example 26A 10 placed with a water-cooled condenser. The mixture is illustrates this method of drying. now heated to reflux and refluxed for 30 minutes. The EXAMPLE 26A heat is removed and the mixture is stirred while cool ing to room temperature. All of the materials appear This example illustrates the preparation of a spray as seemingly a homogenous liquid. This reaction of dried lignin powder, from kraft black liquor. 15 the lignin, mesityl oxide and formaldehyde is believed PROCEDURE: Charge 4000 gms. (4 parts) of the sol to put unsaturated carbonyl groups onto the lignin vent-lignin layer separated in Example 16 into a 5-gal molecule. These groups are reactive and may be ep lon vessel. Then add 2000 gms. (2 parts) of a volatile oxidized as is disclosed in further examples. solvent such as acetone or methyl ethyl ketone and stir. This mixture is then spray-dried where the re 20 EXAMPLE 28 duced pressure removes the solvents and the pow This example illustrates the preparation of an unsatu dered lignin remains. rated carbonyl intermediate from extracted lignin, mesi This method of recovery of lignin from waste black tyl oxide and formaldehyde. liquor from the kraft process is highly advantageous PROCEDURE: Charge 1600 gms. (1.6 parts) of the over previous methods which involved the precipitat 25 separated lignin-solvent layer from Example 5 into a ing of lignin from an aqueous solution, filtering the 5-liter, 3-neck, round-bottom flask equipped with a lignin and then drying the lignin. Lignin so precipitated dropping funnel thermometer, and mechanical stir is to some degree in colloidal form and in such form will rer. Then add 100 ml. (0.1 part) of 38% aqueous form pass through most filters and to this extent is not recov aldehyde dropwise over 15 minutes while the ex erable. The present invention allows the lignin to be 30 tracted lignin is being stirred. Then add 300 ml. (0.3 purified by the separation of the inorganic materials part) of deionized water, over a 10-minute interval. including the pulping chemicals into the water layer, as The mixture is stirred while 30 ml. (0.03 part) of well as all water-soluble material. This is very useful triethylamine is added dropwise over a 10-minute because a polymer may be made from the lignin without interval. The mixture is then stirred for half an hour. having the materials in the water layer interfere with 35 The dropping funnel is replaced with a water-cooled the properties of the polymer. Another advantage is condenser. The mixture is heated to reflux which that the lignin-solvent combination presents the lignin requires a half hour. Then the mixture is refluxed for in a liquid phase where it can be conveniently reacted 30 minutes and then cooled to room temperature over with other chemicals to produce other useful end prod 30 minutes. The lignin is believed to have an unsatu ucts such as resins, adhesives, paints and the like. 40 rated carbonyl structure which is subsequently used The uses of lignin so recovered are extensive. Lignins for epoxidation. have found extensive uses as fillers and extenders for various resins. It has been used as a dispersant, emulsi EXAMPLE 29 fier, grinding aid, protein precipitator, and sequestering This example illustrates the preparation of a reaction agent depending on the particular nature of the lignin. 45 intermediate using mesityl oxide and formaldehyde. In Lignin can be converted chemically to organic chem order to increase the number of unsaturated carbonyl icals, for example vanillin, methyl mercaptan and di groups the amount of mesityl oxide and formaldehyde is methyl sulfide. The potential uses of lignin are quite increased accordingly. extensive. PROCEDURE: Charge 1600 gms. (1.6 parts) of the The following examples illustrate the use of the lig 50 separated lignin-mesityl oxide from Example 5 into a nin-solvent layer produced in accordance with the 5-liter, 3-neck, round-bottom flask equipped with a teachings of Examples 1 through 26, to make a useful dropping funnel, thermometer and mechanical stir end product of an epoxide-lignin resin by way of vari rer. Then add 200 ml. (0.2 part) of mesityl oxide and ous chemical intermediates. These examples relate to stir for 15 minutes. Then add 300 ml. (0.3 part) of producing unsaturated reactive end groups on the lignin 55 38% aqueous formaldehyde dropwise over a 15 molecule which end groups are readily amenable to minute interval while the mixture is being stirred. To epoxidation to produce epoxide-lignin resins. These the mixture is then added 200 ml. (0.2 part) of deion examples include the placing of an unsaturated carbonyl ized water dropwise over a 10-minute interval. Then group on the lignin molecule such as an unsaturated 40 ml. (0.04 part) of triethylamine is added dropwise ketone ester, aldehyde or acid. They also include the 60 over a 10-minute interval. The dropping funnel is placing of an unsaturated nitrogen containing com replaced by a water-cooled condenser and the mix pound on the lignin molecule such as an unsaturated ture is agitated for one-half hour and heated to reflux. nitrile or amide. The mixture is refluxed for one hour and afterwards EXAMPLE 27 cooled to room temperature. 65 This example illustrates the reaction of extracted or EXAMPLE 30 separated lignin with mesityl oxide and formaldehyde, This example illustrates the preparation of a reactive to produce a lignin unsaturated carbonyl intermediate. intermediate which can be used to prepare a lignin 4,265,809 13 14 epoxy resin which has a relatively high number of PROCEDURE: Charge 2000 gms. (2 parts) of Example epoxy groups. 29 into a 5-liter, 3-neck, round-bottom flask equipped PROCEDURE: Charge 1600 gms. (1.6 parts) of ex with a dropping funnel, thermometer and mechanical tracted or separated lignin-solvent from Example 5 stirrer. Cool the mixture from 5 to 10 C. with an ice into a 5-liter, 3-neck, round-bottom flask equipped bath or other cooling equipment. Premix 10 gms. with a dropping funnel thermometer, and mechanical (0.01 part) of magnesium sulfate into 100 ml. (0.1 part) stirrer. Then add 400 ml. (0.4 part) of mesity oxide of deionized water. Add this to the mixture dropwise and stir for 15 minutes. Then add 400 ml. (0.4 part) of over a 10-minute interval while the mixture is being 38% aqueous formaldehyde over a 30-minute inter stirred. Premix 11 gms. of sodium hydroxide in 100 val. To the mixture is then added 200 ml. (0.2 part) of 10 ml. (0.1 part) of deionized water. While the mixture is deionized water dropwise over a 10-minute interval. being maintained between 5' and 10 C. with an ice Then 50 ml. (0.05 part) of triethylamine is added bath, 120 ml. (0.120 part) of 30% aqueous hydrogen dropwise over a 10-minute interval. The dropping peroxide is added dropwise over 30 minutes. The funnel is replaced by a water-cooled condenser and mixture is constantly being stirred during this addi the mixture stirred for 30 minutes, and then heated to 15 tion. If the temperature should rise over 10 C., the reflux. The mixture is refluxed for one hour and 30 addition of hydrogen peroxide is stopped until the minutes and afterwards, cooled to room temperature temperature is less than 10 C. Once the addition of by removing the heat and allowing the mixture to stir. hydrogen peroxide is complete, 400 ml. (0.4 part) of Examples 27, 28, 29 and 30 have illustrated the use of deionized water is added and the mixture is stirred for the lignin-solvent material from Example 5 in the reac 20 one hour while the temperature is maintained be tion to produce the unsaturated carbonyl group on the tween 5' to 10°C. Then 100gms. (0.1 part) of sodium lignin molecule. It will be understood by those skilled in sulfate is added and the mixture stirred for 15 min the art that the lignin-solvent separation from all of the utes. Afterwards, the mixture is poured into a separa Examples 1 through 26 can be used in essentially the tory funnel. After two hours, a layer of epoxy-lignin same way. 25 has started to form on the top part of the separatory funnel and the undissolved sodium sulfate settles on EXAMPLE 31 the bottom. This example illustrates the epoxidation of a reactive intermediate prepared from lignin, mesityl oxide and EXAMPLE 33 formaldehyde with hydrogen peroxide. . . . . 30 This example illustrates the preparation of a lignin PROCEDURE: Charge 2000 gms. (2 parts) of Example epoxy containing eight times the epoxy groups as in 27 into a 5-liter, 3-neck, round-bottom flask, equipped Example 31. with a dropping funnel, thermometer and mechanical PROCEDURE: Charge 2000 gms. (2 parts) of Example stirrer. Cool the mixture to 5 to 10 C. with an ice 30 into a 5-liter, 3-neck, round-bottom flask equipped bath or other cooling equipment. Premix 10 gms, 35 with a dropping funnel, thermometer, and mechani (0.01 part) of magnesium sulfate in 100 ml, (0.1 part) cal stirrer. Cool the mixture between 5' to 10' C. with of deionized water. Add this to the mixture dropwise an ice bath or other cooling equipment. Premix lo over a 10-minute interval while the mixture is being gms. (0.01 part) of magnesium sulfate into 100 ml. (0.1 stirred. Premix 11 gms. of sodium hydroxide in 100 part) of deionized water. Add this to the mixture ml. (0.1 part) of deionized water. While the mixture is dropwise over a 10-minute interval while the mixture being maintained between 5 and 10 C. with an ice is being stirred. Premix 11 gms. of sodium hydroxide bath, 30 ml. (0.03 part) of 30% hydrogen peroxide is in 100 ml. (0.1 part) of deionized water. While the - added dropwise over 30 minutes. The mixture is con mixture is being maintained between 5 and 10 C. stantly being stirred during this addition. If the tem with an ice bath, 240 ml. (0.240 part) of 30% aqueous perature should rise above 10 C., the addition of 45 hydrogen peroxide is added dropwise over one hour. hydrogen peroxide is stopped until the temperature is The mixture is constantly being stirred during this less than 10 C. Once the addition of hydrogen perox addition. If the temperature should rise above 10 C., ide is complete, 400 ml. (0.4 part) of deionized water the addition of hydrogen peroxide is stopped until the is added and the mixture is stirred for one hour while temperature is less than 10° C. Once the addition of the temperature is maintained between 5 and 10 C. 50 hydrogen peroxide is complete, 400 ml. (0.4 part) of Then 100 gms. (0.1 part) of sodium sulfate is added deionized water is added and the mixture is stirred for and the mixture stirred for 15 minutes. Afterwards, one hour while the temperature is being maintained the mixture is poured into a separatory funnel. After between 5 to 10° C. Then 100 gms. (0.1 part) of two hours a layer of epoxy-lignin has started to form sodium sulfate is added and the mixture stirred for 15 on the top part of the separatory funnel and the undis 55 minutes. Afterwards, the mixture is poured into a solved sodium sulfate settles on the bottom. This separatory funnel. After two hours, a layer has occurs as long as the lignin-epoxy has a density less started to form on the top part of the separatory than that of the solution. The presence of low density funnel and the undissolved sodium sulfate settles on solvents would enhance the separation if the lignin the bottom. epoxy has a density greater than the solution and 60 settles to the bottom. After the formation of a layer is EXAMPLE 34 complete, the lignin-epoxy can be separated, and then This example illustrates the preparation of epoxide utilized as an epoxy-resin, groups on the lignin molecule by reacting lignin that contains unsaturated carbonyl groups with sodium per EXAMPLE 32 65 oxide. This example illustrates the preparation of a lignin PROCEDURE: Charge 2000 gms. (2 parts) of Example epoxy containing four times the epoxy groups as in 27 into a 5-liter, 3-neck, round-bottom flask equipped Example 31. with a dropping funnel, thermometer and mechanical 4,265,809 15 16 stirrer. Cool the mixture to 5 to 10 C. with an ice with a dropping funnel, thermometer, and mechani bath or other cooling equipment. Premix 10 gms. cal stirrer. Cool the mixture between 5' to 10° C. with (0.01 part) of magnesium sulfate into 100 ml. (0.1 part) an ice bath. Premix 10 gms. (0.01 part) of magnesium of deionized water. Add this to the mixture dropwise sulfate into 100 ml. (0.1 part) of deionized water. Add over a 10-minute interval while the mixture is being 5 this to the mixture dropwise over a 10-minute intervai stirred. Premix 11 gms. of sodium hydroxide in 100 while the mixture is stirred. Premix 1 1 gms. (O. 11 ml. (0.1 part) of deionized water. While the mixture is part) of sodium hydroxide in 100 ml. (0.1 part) of being maintained between 5 and 10° C. with an ice deionized water. While the mixture is being main bath, 20gms. (0.02 part) of sodium peroxide is added tained between 5' to 10° C. with an ice bath, 40 gms. gradually over 30 minutes. The mixture is constantly 10 (0.04 part) of sodium peroxide is added gradually being stirred during this addition. If the temperature over a 45-minute period. The mixture is constantly should rise above 10° C., the addition of sodium per- being stirred during this addition. If the temperature oxide is stopped until the temperature is less than 10 should rise above 10 C., the addition of sodium per C. Once the addition of sodium peroxide is complete, oxide is stopped until the temperature is less than 10 400 ml. (0.4 part) of deionized water is added and the 15 C. Once the addition of sodium peroxide is complete, mixture is stirred for one hour while the temperature 400 ml. (0.4 part) of deionized water is added and the is being maintained between 5' to 10° C. Then 100 mixture is stirred for one hour while being maintained gms. (0.1 part) of sodium sulfate is added and the in the 5' to 10° C. range. Then 100 gms. (0.1 part) of mixture stirred for 15 minutes. Afterwards, the mix- sodium sulfate is added and the mixture stirred for 15 ture is poured into a separatory funnel. After two 20 minutes. Afterwards, the mixture is poured into a hours, a layer has started to form on the top part of separatory funnel. After two hours, a layer has the separatory funnel and the dissolved sodium sul- started to form on the top in the separatory funnel fate settles on the bottom. This occurs as long as the and the undissolved sodium sulfate settles on the lignin-epoxy has a density less than that of the solu- bottom. tion. The presence of low-density solvents would 25 enhance the separation if the lignin-epoxy has density EXAMPLE 37 greater than the solution and settles to the bottom. This example illustrates the epoxidation of a reactive After the formation of a layer is complete, the lignin lignin intermediate with sodium peroxide, which con epoxy can be separated, and then utilized as an epoxy tains four times the epoxy groups as Example 35. resin. 30 PROCEDURE: Charge 2000 gms. (2 parts) of Example 30 into a 5-liter, 3-neck, round-bottom flask equipped EXAMPLE 35 with a dropping funnel, thermometer and mechanical This example illustrates the epoxidation of a reactive stirrer. Cool the mixture between 5 to 10° C. with an intermediate prepared from mesityl oxide, lignin and ice bath. Premix 10 gms. (0.01 part) of magnesium formaldehyde by sodium peroxide. 35 sulfate into 100 ml. (0.1 part) of deionized water. Add PROCEDURE: Charge 2000 gms. (2 parts) of Example this to the mixture dropwise over a 10-minute interval 29 into 5-liter, 3-neck, round-bottom flask equipped while the mixture is stirring. Premix 11 gms. (0.11 with a dropping funnel, thermometer and mechanical part) of sodium hydroxide in 100 ml. (0.1 part) of stirrer. Cool the mixture between 5' to 10° C. with an deionized water. While the mixture is being main ice bath or other cooling equipment. Premix 10 gms. 40 tained between 5' to 10° C. with an ice bath, 80 gms. (0.01 part) of magnesium sulfate into 100 ml. (0.1 part) (0.08 part) of sodium peroxide is added gradually of deionized water. Add this to the mixture dropwise over a one-hour period. The mixture is constantly over a 10-minute interval while the mixture is being being stirred during this addition. If the temperature stirred. Premix 11 gms. of sodium hydroxide in 100 should rise above 10' C., the addition of sodium per ml. (0.1 part) of deionized water. While the mixture is 45 oxide is stopped until the temperature is less than 10 being maintained between 5 to 10 C. with an ice C. Once the addition of sodium peroxide is complete, bath, 20 gms. (0.02 part) of sodium peroxide is added 400 ml. (0.4 part) of deionized water is added and the gradually over 30 minutes. The mixture is constantly mixture is stirred for one hour while being maintained being stirred during this addition. If the temperature in the 5' to 10° C. range. Then 100 gms. (0.1 part) of should rise above 10 C., the addition of sodium per 50 sodium sulfate is added and the mixture stirred for 15 oxide is stopped until the temperature is less than 10 minutes. Afterwards, the mixture is poured into a C. Once the addition of sodium peroxide is complete, separatory funnel. After two hours, a layer has 400 ml. (0.4 part) of deionized water is added and the started to form on the top in the separatory funnel mixture is stirred for one hour while the temperature and the undissolved sodium sulfate settles on the is being maintained between 5' to 10° C. Then 100 55 bottom. gms. (0.1 part) of sodium sulfate is added and the mixture stirred for 15 minutes. Afterwards, the mix EXAMPLE 38 ture is poured into a separatory funnel. After two This example illustrates the reaction of acrylonitrile hours, a layer has started to form on the top part of with lignin to produce an unsaturated amide or interne the separatory funnel and the undissolved sodium 60 diate which is chemicily bonded to the lignin molecule. sulfate settles on the bottom. This unsaturated intermediate can then be epoxidized using the procedures of Examples 31 through 37. EXAMPLE 36 PROCEDURE: Charge 1600 gms. (1.6 parts) of the This example illustrates the preparation of a lignin separated lignin-butyl ether from Example 21 into a epoxy containing twice the epoxy groups as Example 65 5-liter, 3-neck, round-bottom flask equipped with a 35. dropping funnel, thermometer and mechanical stir PROCEDURE: Charge 2000 gms. (2 parts) of Example rer. Then add 200 ml. (0.2 part) of acrylonitrile and 29 into a 5-liter, 3-neck, round-bottom flask equipped stir for 15 minutes. Then add 300 ml. (0.3 part) of 4,265,809 17 18 38% aqueous formaldehyde dropwise over a 15 ter. Add this mixture dropwise over a period of one minute interval while the mixture is being stirred. To half hour. Then stir this mixture at room temperature the mixture is then added 200 ml. (0.2 part) of deion for one hour. Then heat to reflux and reflux for one ized water dropwise over a 10-minute interval. Then hour. Afterwards, the mixture is cooled to room tem 40 ml. (0.04 part) of triethylamine is added dropwise perature. over a 10-minute interval. The dropping funnel is replaced by a water-cooled condenser and the mix EXAMPLE 42 ture is agitated for one-half hour and heated to reflux. This example illustrates the reaction of extracted or The mixture is refluxed for one hour and afterwards, separated lignin with methyl cyanoacetate to produce cooled to room temperature. 10 an unsaturated nitrile which is chemically bonded to the lignin molecule. EXAMPLE 39 PROCEDURE: Charge 2000 gms. (2 parts) of ex This example illustrates the reaction of acrolein with tracted or separated lignin from Example 16 into a lignin to produce an unsaturated carbonyl which is 5-liter, 3-neck, round-bottom flask equipped with a chemically bonded to the lignin molecule. This can be 15 mechanical stirrer, thermometer and dropping fun epoxidized by the procedure of Examples 31 through nel. Then premix 40 gms. (0.04 part) of sodium hy 37. droxide in 300 ml. of deionized water and add drop PROCEDURE: Charge 1600 gms. (1.6 parts) of the wise over 15 minutes. Then premix 100 gms. (0.1 separated lignin-mesityl oxide from Example 21 into a part) of methylcyanoacetate in 200gms. (0.2 part) of 5-liter, 3-neck, round-bottom flask equipped with a 20 deionized water. Add this mixture dropwise over a dropping funnel, thermometer, and mechanical stir period of one-half hour. Then stir this mixture at rer. Then add 200 ml. (0.2 part) of acrolein and stir for room temperature for one hour. Then heat to reflux 15 minutes. Then add 300 ml. (0.3 part) of 38% aque and reflux for one hour. Afterwards, the mixture is ous formaldehyde dropwise over a 15-minute interval cooled to room temperature. while the mixture is being stirred. To the mixture is 25 then added 200 ml. (0.2 part) of deionized water drop EXAMPLE 43 wise over a 10-minute interval. Then 40 ml. (0.04 This example illustrates the reaction of lignin with part) of triethylamine is added dropwise over a 10 diethylmalonate to produce an unsaturated ester which minute interval. The dropping funnel is replaced by a can then be epoxidized. water-cooled condenser and the mixture is agitated 30 PROCEDURE: Charge 2000 gms. (2 parts) of ex for one-half hour and heated to reflux. The mixture is tracted or separated lignin from Example 16 into a refluxed for one hour and afterwards, cooled to room 5-liter, 3-neck, round-bottom flask equipped with a temperature. mechanical stirrer, thermometer and dropping fun EXAMPLE 40 nel. Then premix 40 gms. (0.04 part) of sodium hy 35 droxide in 300 ml. of deionized water and add drop This example illustrates the reaction of extracted or wise over 15 minutes. Then premix 100 gms. (0.1 separated:lignin with cyanoacetic acid to produce an part) of diethyl malonate in 200 gms. (0.2 part) of unsaturated nitrile which is chemically bonded to the deionized water. Add this mixture dropwise over a lignin molecule. period of one-half hour. Then stir this mixture at PROCEDURE: Charge 2000 gms. (2 parts) of ex 40 room temperature for one hour. Then heat to reflux tracted or separated lignin from Example 16 into a and reflux for one hour. Afterwards, the mixture is 5-liter, 3-neck, round-bottom flash equipped with a cooled to room temperature. mechanical stirrer, thermometer and dropping fun nel. Then premix 40 gms. (0.04 part) of sodium hy EXAMPLE 44 droxide in 300 ml. of deionized water and add drop 45 This example illustrates the reaction of dimethyl ma wise over 15 minutes. The mixture is then stirred for lonate with extracted or separated lignin to produce an 15 minutes. Then premix 100gms. (0.1 part) of cyano unsaturated ester which can then be epoxidized with acetic acid in 200 gms. (0.2 part) of deionized water. alkaline hydrogen peroxide. Add this mixture dropwise over a period of one-half PROCEDURE: Charge 2000 gms. (2 parts) of ex hour. Then stir this mixture at room temperature for 50 tracted or separated lignin from Example 16 into a one hour. Then heat to reflux and reflux for one hour. 5-liter, 3-neck, round-bottom flask equipped with a Afterwards, the mixture is cooled to room tempera mechanial stirrer, thermometer, and dropping funnel. tute. Then premix 40 gms. (0.04 part) of sodium hydroxide EXAMPLE 41 in 300 ml. of deionized water and add dropwise over 55 15 minutes. Then premix 100 gms. (0.1 part) of di This example illustrates the reaction of extracted or methyl malonate in 200 gms. (0.2 part) of deionized separated lignin with ethyl cyanoacetate t produce an water. Add this mixture dropwise over a period of unsaturated nitrile which is chemically bonded to the one-half hour. Then stir this mixture at room temper lignin molecule. ature for one hour. Then heat to reflux and reflux for PROCEDURE: Charge 2000 gms. (2 parts) of ex one hour. Afterwards, the mixture is cooled to room tracted or separated lignin from Example 16 into a temperature. 5-liter, 3-neck, round-bottom flash equipped with a mechanical stirrer, thermometer and dropping fun EXAMPLE 45 nel. Then premix 40 gms. (0.04 part) of sodium hy This example illustrates the reaction of extracted or droxide in 300 ml. of deionized water and add drop 65 separated lignin with malonic acid to produce an unsat wise over 15 minutes. The mixture is then stirred for urated acid which can then be epoxidized. 15 minutes. Then premix 100 gms. (0.1 part) of ethyl PROCEDURE: Charge 2000 gms. (2 parts) of ex cyanoacetate in 200 gms. (0.2 part) of deionized wa tracted or separated lignin from Example 16 into a 4,265,809 19 20 5-liter, 3 -neck, round-bottom flask equipped with a A and B are blended together and heated slowly until mechanical stirrer, thermometer, and dropping fun the mixture thins out. Then the mixture is heated nel. Then premix 40 gms. (0.04 part) of sodium hy under agitation for one-half hour until droplets of droxide in 300 ml. of deionized water and add drop the mixture form long fibers of approximately 2 ft. wise over 15 minutes. Then premix 100 gms. (0.1 in length. At this time the mixture can then be cast part) of malonic acid in 200gms. (0.02 part) of deion into a mold. On cooling, a dark solid plastic results ized water. Add this mixture dropwise over a period of one-half hour. Then stir this mixture at room tem EXAMPLE 50 perature for one hour. Then heat to reflux and reflux This example illustrates the preparation of a plastic for one hour. Afterwards, the mixture is cooled to 10 from epoxidized lignin by using an aliphatic amine cur room temperature. ing agent. Epoxidation of Examples 40 through 45 can be car A. 100 parts of epoxidized lignin from Example 32. ried out in the same manner as disclosed in Examples 31 B. 15 parts triethylenetetramine through 37. C. 100 parts of epoxidized lignin from Example 32. The following examples teach the use of and method 15 PROCEDURE: Blend A and B and heat to 100 C. for of making several end products from the epoxide-lignin one-half hour and then add C. The mixture is then resins of Examples 31 through 37. heated at 200° C. until fibers 2 ft. long form from the droplets of the mixture. The mixture is then cast into EXAMPLE 46 a mold and a tough, dark plastic results. This example illustrates the preparation of an adhe 20 sive from epoxidized lignin. EXAMPLE 51 A. 100 parts epoxidized lignin (from Examples 33) This example illustrates the preparation of a plastic 50 parts tabular alumina from epoxidized lignin and a polysulfide resin. B. 50 parts Thiokol LP-30, (polysulfide resin) 10 parts A. 100 parts of epoxidized lignin from Example 33. DMP-30 tri-(dimethylaminoethyl) Phenol (cata 25 B. 120 parts of Thiokol polysulfide resin (LP-3) lyst) C. 10 parts of tri-(dimethyaminoethyl) phenol PROCEDURE: The filler (tabular alumina) is mixed PROCEDURE: Blend B and C and then add A and mix with the epoxidized lignin preferably by grinding on well for 10 minutes. The mixture is then poured into a mold and at the end of 6 hours, has cured to a tough a 3-roll paint mill. Then the mixture of liquid polysul 30 plastic. fide and catalyst is blended in, care being taken to Another illustration of the invention involves the use avoid the entrapment of air. Both A and B are stable of a lignin which has been separated from the waste but their mixture has a short pot life, well under an black cooking liquor of the kraft pulping process in a hour, therefore, mix only enough for 10 to 15 minutes manner different than that disclosed above. of operation, Because of DMP-30, cure can take place 35 This lignin is separated, in principle, by reducing the at room temperature. pH of the black liquor to a level where a lignin fraction EXAMPLE 47 precipitates or separates from the aqueous medium. This lignin is normally separated and dried resulting in This example illustrates the preparation of an adhe a powder-like product. The lignin resulting may, also, sive from epoxidized lignin, with a polyamide resin such be produced in a slurry-like suspension. The pH of the as Versamid 115 resin. black liquor is normally reduced by the addition of an A. 100 parts of epoxidized lignin from Example 33. acid and separation of lignin may result at a pH 8 or 9 B. 70 parts Versamid 115 resin. and, also, results at a pH below 7. This illustration of the C. Filler as desired. invention is best understood from the following exam PROCEDURE: Simply blend all of the components 45 together. The Versamids cure slowly at room tem ples all of which involve the use of a lignin produced as perature which allows for longer working times. just described above. EXAMPLE 52 EXAMPLE 48 This example illustrates the reaction of lignin, pro This example illustrates the preparation of an adhe 50 duced as just described above, with mesityl oxide and sive from epoxidized lignin, Versamid polyamide, and a formaldehyde to produce a lignin unsaturated carbonyl curing agent to provide a faster cure. intermediate. A. 100 parts of epoxidized lignin from Example 33. PROCEDURE: Dissolve 18 gms. (0.018 part) of so B. 35 parts Versamid 115 dium hydroxide into 1600 gms. (1.6 parts) of deion C. 5 parts DMP-30 tri-(dimethylaminoethyl) phenol 55 ized water. Then slowly add 500 gms. (0.5 part) of (catalyst) Indulin AT (a powdered kraft lignin produced by D. Filler as desired Westvaco Corporation) while the mixture is agitated. PROCEDURE: The filler is blended with the epoxi Then charge this premix into a 5-liter, 3-neck, round dized lignin and a reactive diluent is added to reduce bottom flask equipped with a thermometer, dropping the viscosity if necessary. 60 funnel, and mechanical stirrer. Add 98 gms. (0.098 EXAMPLE 49 part) of mesityl oxide dropwise over ten minutes while the mixture is agitated. Then add 80 gms. (0.08 This example illustrates the preparation of a plastic part) of 40% aqueous formaldehyde dropwise over a from epoxidized lignin. ten-minute interval. To this mixture add 8 gms. (0.008 PROCEDURE: 65 part) of triethylamine. A. 100 parts of epoxidized lignin from Example 31. The dropping funnel is replaced with a water cooled B. 30 parts Lubrizol CA-23 epoxy curing agent (poly condenser. The mixture is heated to reflux and refluxed amide) for 30 minutes. The heat is removed and the mixture is 4,265,809 21 22 stirred while cooling to room temperature. All of the causes the lignin-epoxy resin to become insoluble materials appear as a seemingly homogenous liquid. thereby precipitating out of the reaction medium. This reaction of the lignin, mesityl oxide and formalde hyde is believed to put unsaturated carbonyl groups EXAMPLE 55 onto the lignin molecule. These groups are reactive and 5 This example illustrates the epoxidation of a reactive may be epoxidized as is disclosed in further examples. intermediate prepared from lignin, such as Indulin AT, mesityl oxide and formaldehyde. This example also EXAMPLE 53 illustrates the separation of the final lignin-epoxy resin This example illustrates the reaction of a lignin with from the reaction mixture by the use of an acid such as mesity oxide and formaldehyde to produce a lignin 10 acetic acid. unsaturated carbonyl intermediate. This example will produce alignin-epoxy resin with fewer epoxide groups PROCEDURE: Charge 2300 gms. (2.3 parts) of Exam than Example 52. ple 52 into a 5-liter, 3-neck round-bottom flask PROCEDURE: Dissolve 18 gms. (0.018 part) of so equipped with a dropping funnel, thermometer and dium hydroxide into 1600 gms. (1.6 parts) of deion 15 mechanical stirrer. Cool the mixture to 5 to 10 C. ized water. Then slowly add 500 gms. (0.5 part) of with an ice bath or other cooling equipment. Indulin AT (a powdered kraft lignin produced by Premix 8 gms. (0.008 parts) of magnesium sulfate. in Westvaco Corporation) while the mixture is being 200 gms. (0.2 parts) of deionized water. Add this mix agitated. Then charge this premix into a 5-liter, 3 ture dropwise over a ten-minute interval while the mix neck, round-bottom flask equipped with a thermome ture is being stirred. While the mixture is being main ter, dropping funnel, and mechanical stirrer. Add 18 tained between 5 and 10 C. with an ice bath, 100 ml. gms. (0.018 part) of mesityl oxide dropwise over ten (0.1 part) of 30% hydrogen peroxide is added dropwise minutes, while the mixture is agitated. Then add 14 over 30 minutes. The mixture is constantly being stirred gms. (0.014 part) of 40% aqueous formaldehyde during this addition. If the temperature should rise dropwise over a ten-minute interval. To this mixture 25 above 10 C., the addition of hydrogen peroxide is add 8 gms. (0.008 part) of triethylamine. stopped until the temperature is less than 10 C. Once The dropping funnel is replaced with a water-cooled the addition of hydrogen peroxide is complete the mix condenser. The mixture is heated to reflux and refluxed ture is stirred for one hour while the temperature is for 30 minutes. The heat is removed and the mixture is being maintained between 5' and 10 C. Premix 30 ml. stirred while cooling to room temperature. All of the 30 (0.03 part) of glacial acetic acid in 70 ml. (0.07 part) of materials appear as a seemingly homogenous liquid. deionized water. This premix is then added slowly to This reaction of the lignin, mesityl oxide and formalde the reaction mixture while it is being agitated. The hyde is believed to put unsaturated carbonyl groups mixture becomes very thick and the epoxy-lignin resin onto the lignin molecule. These groups are reactive and 35 is no longer water-soluble and can be easily separated may be epoxidized as is disclosed in further examples. from the reaction solvents by various means such as EXAMPLE 54 filtering or spray-drying. This example illustrates the epoxidation of a reactive EXAMPLE 56 intermediate prepared from lignin, such as Indulin At, 40 This example illustrates the epoxidation of a reactive mesityl oxide and formaldehyde with hydrogen perox intermediate prepared from lignin, such as Indulin AT, ide. mesityl oxide and formaldehyde at 25 C. instead of 5 PROCEDURE: Charge 2300 gms. (2.3 parts) of Exam to 10 C. ple 52 into a 5-liter, 3-neck round bottom flask PROCEDURE: Charge 2300 gms. (2.3 parts) of Exam equipped with a dropping funnel, thermometer and 45 ple 52 into a 5-liter, 3-neck, round-bottom flask mechanical stirrer. Cool the mixture to 5 to 10 C. equipped with a dropping funnel, thermometer and with an ice bath or other cooling equipment. mechanical stirrer. Cool the mixture to 25 C. with an Premix 8 gms. (0.008 parts) of magnesium sulfate in ice bath or other cooling equipment. Premix 8 gms. 200 gms. (0.2 parts) of deionized water. Add this mix (0.008 part) of magnesium sulfate in 200 gms. (0.2 ture dropwise over a ten-minute interval while the mix 50 ture is being stirred. While the mixture is being main part) of deionized water. Add this mixture dropwise tained between 5' and 10 C. with an ice bath, 100 ml. over a ten-minute interval while the mixture is being (0.1 part) of 30% hydrogen peroxide is added dropwise stirred. While the mixture is being maintained be over 30 minutes. The mixture is constantly being stirred tween 20 and 25 C. with an ice bath, 100 ml. (0.1 during this addition. If the temperature should rise 55 part) of 30% hydrogen peroxide is added dropwise above 10 C., the addition of hydrogen peroxide is over 30 minutes. The mixture is constantly being stopped until the temperature is less than 10° C. Once stirred during this addition. If the temperature should the addition of hydrogen peroxide is complete the mix rise above 25 C., the addition of hydrogen peroxide ture is stirred for one hour while the temperature is is stopped until the temperature is less than 25 C. being maintained between 5 and 10 C. Then the mix 60 Once the addition of hydrogen peroxide is complete ture is poured into a 3000 ml. beaker or like container. the mixture is stirred for one hour while the tempera Then 100 gms. (0.1 part) of sodium sulfate is added and ture is maintained between 20 and 25 C. Then the the mixture stirred for 15 minutes. The mixture now mixture is poured into a 3000 ml. beaker or like con becomes very thick and the lignin-epoxy resin can now tainer. Then 100 gms. (0.1 part) of sodium sulfate is be easily separated by various means, such as filtering or 65 added and the mixture stirred for 15 minutes. The spray drying. The resin can also be separated from the mixture now becomes very thick and the lignin reaction medium by acidifying with acetic, sulfuric or epoxy resin can now be easily separated by various hydrochloric acid or with carbon dioxide gas, which means, such as filtering or spray drying. 4,265,809 23 24 PROCEDURE: Dissolve 18 gms. (0.018 part) of so EXAMPLE 57 dium hydroxide into 1600 gms. (.6 parts) of deion This example illustrates the epoxidation of a reactive ized water. Then slowly add 500 gms. (0.5 part) of intermediate prepared from lignin, such as Indulin AT, Indulin AT (a kraft lignin produced by Westvaco mesityl oxide and formaldehyde. This epoxidation pro Corporation) while the mixture is being agitated. duces a lignin-epoxy resin with about one-fifth as many Then charge this premix into a 5-liter, 3-neck round epoxy groups as Example 54. bottom flask equipped with a thermometer, dropping PROCEDURE: Charge 2150 gms. (2.15 parts) of Ex funnel, and mechanical stirrer. Add 60 gms. (0.060 ample 53 into a 5-liter, 3-neck, round-bottom flask part) of acrolein dropwise over ten minutes while the equipped with a dropping funnel, thermometer and 10 mixture is being agitated. Then add 80 gms. (0.08 mechanical stirrer. Cool the mixture to 5 to 10 C. part) of 40% aqueous formaldehyde dropwise over a with an ice bath or other cooling equipment. Premix ten-minute interval. To this mixture add 8 gms. (0.008 3 gms. (0.003 part) of magnesium sulfate in 200gms. part) of triethylamine. (0.2 part) of deionized water. Add this mixture drop wise over a ten-minute interval while the mixture is 5 The dropping funnel is replaced with a water-cooled being stirred. While the mixture is being maintained condenser. The mixture is heated to reflux and refluxed between 5 and 10 C., with an ice bath, 17 ml. (0.017 for 30 minutes. The heat is removed and the mixture is part) of 30% hydrogen peroxide is added dropwise stirred while cooling to room temperature. All of the over 30 minutes. The mixture is constantly being materials appear as a seemingly homogenous liquid. stirred during this addition. If the temperature should 20 This reaction of the lignin, acrolein and formaldehyde is rise above 10° C., the addition of hydrogen peroxide believed to put unsaturated carbonyl groups onto the is stopped until the temperature is less than 10° C. lignin molecule. These groups are reactive and may be Once the addition of hydrogen peroxide is complete epoxidized as is disclosed in further examples. the mixture is stirred for one hour while the tempera EXAMPLE 60 ture is being maintained between 5 and 10° C. Then 25 the mixture is poured into a 3000 ml. beaker or like This example illustrates the reaction of indulin AT container. Then 100 gms. (0.1 part) of sodium sulfate lignin with cyanoacetic acid to produce an unsaturated is added and the mixture stirred for 15 minutes. The nitrile which is chemically bonded to the lignin mole mixture now becomes very thick and the lignin cule. This unsaturated nitrile can then be epoxidized by epoxy resin can now be easily separated by various 30 using the procedures of Examples 54 through 57. means, such as filtering or spray drying. PROCEDURE: Dissolve 28 gms. (0.028 part) of so dium hydroxide into 1600 gms. (1.6 parts) of deion EXAMPLE 58 ized water. Then slowly add 500 gms. (0.5 part) of This example illustrates the reaction of acrylonitrile Indulin AT (a kraft lignin produced by Westvaco with Indulin AT lignin to produce an unsaturated amide 35 Corporation) while the mixture is agitated. Then or intermediate which is chemically bonded to the lig charge this premix into a 5-liter, 3-neck, round-bot nin molecule. This unsaturated intermediate can then be tom flask equipped with a mechanical stirrer, ther epoxidized by using the procedures of Examples 54 mometer, and dropping funnel. Then premix 100gns. through 57. (0.10 part) of cyanoacetic acid in 200 gms. (0.2 part) PROCEDURE: Dissolve 18 gms. (0.018 part) of so 40 of deionized water. Add this mixture dropwise over a dium hydroxide into 1600 gms. (1.6 parts) of deion period of one-half hour. Then stir this mixture at ized water. Then slowly add 500 gms. (0.5 part) of room temperature for one hour. Then replace the Indulin AT (a kraft lignin produced by Westvaco dropping funnel with a water-cooled condenser, heat Corporation) while the mixture is being agitated. to reflux and reflux for one hour. Afterward the reac Then charge this premix into a 5-liter, 3-neck round 45 tion is cooled to room temperature. bottom flask equipped with a thermometer, dropping funnel, and mechanical stirrer. Add 100 gms. (0.10 EXAMPLE 6 part) of acrylonitrile dropwise over ten minutes while This example illustrates the reaction of Indulin AT the mixture is being agitated. Then add 80 gms. (0.08 lignin with ethyl cyanoacetate to produce an unsatu part) of 40% aqueous formaldehyde dropwise over a 50 rated nitrile which is chemically bonded to the lignin ten-minute interval. To this mixture add 8 gms. (0.008 molecule. This unsaturated nitrile can then be epoxi part) of triethylamine. dized by using the procedures of Examples 54 through The dropping funnel is replaced with a water-cooled 57. condenser. The mixture is heated to reflux and refluxed PROCEDURE: Dissolve 28 gms. (0.028 part) of so for 30 minutes. The heat is removed and the mixture is 55 dium hydroxide into 1600 gms. (1.6 parts) of deion stirred while cooling to room temperature. All of the ized water. Then slowly add 500 gms. (0.5 part) of materials appear as a seemingly homogenous liquid. Indulin AT (a kraft lignin produced by Westvaco This reaction of the lignin, acrylonitrile and formalde Corporation) while the mixture is being agitated. hyde is believed to put unsaturated amide groups onto Then charge this premix into a 5-liter, 3-neck round the lignin molecule. These groups are reactive and may 60 bottom flask equipped with a mechanical stirrer, ther be epoxidized as is disclosed in further examples. mometer, and dropping funnel. Then premix 20 gins. (0.12 part) of ethylcyanoacetate in 200gms. (0.2 part) EXAMPLE 59 of deionized water. Add this mixture dropwise over a This example illustrates the reaction of acrolein with period of one-half hour. Then stir this mixture at Indulin AT lignin to produce an unsaturated carbonyl 65 room temperature for one hour. Then replace the which is chemically bonded to the lignin molecule. This dropping funnel with a water-cooled condenser, heat unsaturated intermediate can then be epoxidized by to reflux and reflux for one hour. Afterward the reac using the procedures of Examples 54 through 57. tion is cooled to room temperature. 4,265,809 25 26 EXAMPLE 62 EXAMPLE 65 This example illustrates the reaction of Indulin AT This example illustrates the reaction of a lignin epoxy lignin with methylcyanoacetate to produce an unsatu resin with a polyazelaic polyanhydride curing agent. rated nitrile which is chemically bonded to the lignin This reaction produces a hard, glossy plastic whose molecule. This unsaturated nitrile can then be epoxi properties depend on the ratio of curing agent to lignin dized by using procedures of Examples 54 through 57. epoxy resin and also how long the material is cured. PROCEDURE: Dissolve 28 gms, (0.028 part) of so PROCEDURE: Melt B in a suitable pyrex beaker and dium hydroxide into 1600 gms. (1.6 parts) of deion then add A and mix well and heat to 400 F. The ized water. Then slowly add 500 gms. (0.5 part) of 10 mixture reacts to produce a viscous liquid which on Indulin AT (a kraft lignin produced by Westvaco continued heating, will produce fibers of any length Corporation) while the mixture is being agitated. desired from a bead drawn from the melt. Then charge this premix into a 5-liter, 3-neck round A= 100 parts of dried epoxidized lignin from Exam bottom flask equipped with a mechanical stirrer, ther ple 54. mometer and dropping funnel. Then premix 110 gms. 15 B=35 parts polyazelaic polyanhydride (purchased (0.11 part) of methyl cyanoacetate in 200 gms. (0.2 from Emery Industries). part) of deionized water. Add this mixture dropwise over a period of deionized water. Add this mixture EXAMPLE 66 dropwise over a period of one-half hour. Then stir This example illustrates the epoxidation of an Indulin this mixture at room temperature for one hour. Then 20 AT unsaturated carbonyl with sodium peroxide. replace the dropping funnel with a water-cooled PROCEDURE: Charge 2300 gms. (2.3 parts) of Exam condenser, heat to reflux and reflux for one hour. ple 52 into a 5-liter, 3-neck, round-bottom flask Afterwards the reaction is cooled to room tempera equipped with a dropping funnel, thermometer and tre. mechanical stirrer. Cool the mixture to 5’ to 10° C. 25 with an ice bath or other cooling equipment. EXAMPLE 63 Premix 8 gms. (0.008 part) of magnesium sulfate in This example illustrates the reaction of Indulin AT 200gms. (0.2 part) of deionized water. Add this mixture lignin with dimethylmalonate to produce an unsatu dropwise over a ten-minute interval while the mixture is rated ester which is chemically bonded to the lignin being stirred. While the mixture is being maintained molecule. This unsaturated ester can then be epoxidized 30 between 5 and 10 C. with an ice bath, 80 gms. (0.08 by using the procedures of Examples 54 through 57. part) of sodium peroxide dissolved in 200 ml. (0.2 part) PROCEDURE: Dissolve 20 gms. (0.02 part) of sodium of deionized water is added dropwise over 30 minutes. hydroxide into 1600 gms. (1.6 parts) of deionized The mixture is constantly being stirred during this addi water. Then slowly add 500gms. (0.5 part) of Indulin tion. If the temperature should rise above 10 C., the AT (a kraft lignin produced by Westvaco Corpora 35 addition of sodium peroxide is stopped until the temper tion) while the mixture is agitated. Then charge this ature is less than 10 C. Once the addition of sodium premix into a 5-liter, 3-neck, round-bottom flask peroxide is complete the mixture is stirred for one hour equipped with a mechanical stirrer, thermometer, and while the temperature is being maintained between 5 dropping funnel. Then premix 140gms. (0.14 part) of and 10 C. Then the mixture is poured into a 3000 ml. dimethylmalonate in 200 gms. (0.2 part) of deionized 40 beaker or like container. Then 100 gms. (0.1 part) of water. Add this mixture dropwise over a period of sodium sulfate is added and the mixture stirred for 15 one-half hour. Then stir this mixture at room temper minutes. The mixture now becomes very thick and the ature for one hour. Then replace the dropping funnel lignin-epoxy resin can now be easily separated by vari with a water-cooled condenser, heat to reflux and ous means, such as filtering or spray drying. reflux for one hour. Afterward the reaction is cooled 45 to room temperature. EXAMPLE 67 This example illustrates the epoxidation of an Indulin EXAMPLE 64 AT unsaturated carbonyl with sodium peroxide to pro This example illustrates the reaction of Indulin AT duce an epoxy-lignin resin which has one-fifth as many lignin with malonic acid to produce an unsaturated acid 50 epoxy groups as Example 66. which is chemically bonded to the lignin molecule. This PROCEDURE: Charge 2150 gms. (2.15 parts) of Ex unsaturated acid can then be epoxidized by using proce ample 53 into a 5-liter, 3-neck, round-bottom flask dures of Examples 54 through 57. equipped with a dropping funnel, thermometer and PROCEDURE: Dissolve 28 gms. (0.028 part) of so mechanical stirrer. Cool the mixture to 5 C. to 10 C. dium hydroxide into 1600 gms, (1.6 parts) of deion 55 with an ice bath or other cooling equipment. ized water. Then slowly add 500 gms. (0.5 part) of Premix 3 gms. (0.003 part) of magnesium sulfate in Indulin AT (a kraft lignin produced by Westvaco 200 gms. (0.2 part) of deionized water. Add this mixture Corporation) while the mixture is being agitated. dropwise over a ten-minute interval while the mixture is Then charge this premix into a 5-liter, 3-neck, round being stirred. While the mixture is being maintained bottom flask equipped with a mechanical stirrer, ther 60 between 5 and 10 C. with an ice bath, 16 gms. (0.016 mometer and dropping funnel. Then premix 110 gms. part) of sodium peroxide dissolved in 200 ml (0.20 part) (0.11 part) of malonic acid in 200 gms. (0.2 part) of of deionized water is added dropwise over 30 minutes. deionized water. Add this mixture dropwise over a The mixture is constantly stirred during this addition. If period of one-half hour. Then stir this mixture at the temperature should rise about 10°C., the addition of room temperature for one hour. Then replace the 65 sodium peroxide is stopped until the temperature is less dropping funnel with a water-cooled condenser, heat than 10 C. Once the addition of sodium peroxide is to reflux and reflux for one hour. Afterward the reac complete the mixture is stirred for one hour while the tion is cooled to room temperature. temperature is being maintained between 5 and 10 C. 4,265,809 27 28 Then the mixture is poured into a 3000 ml. beaker or line container. Then 100 gms. (0.1 part) of sodium sul EXAMPLE 72 fate is added and the mixture stirred for 15 minutes. The This example illustrates the separation of lignin from mixture now becomes very thick and the lignin-epoxy kraft black liquor by using dicyclopentadiene alcohol. resin can now be easily separated by various means, This material is normally considered to be only a partial such as filtering or spray drying. solvent for lignin. PROCEDURE: Charge 400 ml. (4 parts) of kraft black EXAMPLE 68 liquor (50% solids) into a one liter vessel. Add 100 This example illustrates the separation of lignin from ml. (1 part) of water and stir. Then add 100 ml. (1 kraft black liquor by using decyl alcohol, an organic O part) of dicyclopentadiene alcohol. While this mix alcohol, which is a material which is considered only a ture is being stirred, add 25 ml. (0.25 parts) of 80% partial solvent for lignin. acetic acid slowly over a five minute interval. As PROCEDURE: Charge 400 ml. (4 parts) of kraft black soon as the viscosity of the mixture starts to increase liquor (50% solids) into a one liter vessel. Add 100 the stirring may be discontinued and a layer starts to ml. (1 part) of water and stir. Then add 100 ml. (1 15 form which contains the lignin. part) of decyl alcohol. While this mixture is being stirred, add 25 ml. (0.25 parts) of 80% acetic acid EXAMPLE 73 slowly over a five minute interval. As soon as the This example illustrates the separation of lignin from viscosity of the mixture starts to increase the stirring kraft black liquor by using 2-heptanone, an organic may be discontinued and a layer starts to form which 20 ketone. This material is normally considered to be only contains the lignin. a partial solvent for lignin. PROCEDURE: Charge 400 ml. (4 parts) of kraft black EXAMPLE 69 liquor (50% solids) into a one liter vessel. Add 100 This example illustrates the separation of lignin from ml. (1 part) of water and stir. Then add 100 ml. (1 kraft black liquor by using iso-octyl alcohol, an ali 25 part) of 2-heptanone. While this mixture is being phatic alcohol, a partial solvent for lignin. stirred, add 25 ml. (0.25 parts) of 80% acetic acid PROCEDURE: Charge 400 ml. (4 parts) of kraft black slowly over a five minute interval. As soon as the liquor (50% solids) into a one liter vessel. Add 100 viscosity of the mixture starts to increase the stirring ml. (1 part) of water and stir. Then add 100 ml. (1 may be discontinued and a layer starts to form which part) of iso-octyl alcohol. While this mixture is being 30 contains the lignin. stirred, add 26 ml. (0.25 parts) of 80% acetic acid slowly over a five minute interval. As soon as the EXAMPLE 74 viscosity of the mixture starts to increase the stirring This example illustrates the separation of lignin from may be discontinued and a a layer starts to form 35 kraft liquor by using dimethyl-4-heptanone, an organic which contains the lignin. ketone. This material is normally considered to be only a partial solvent for lignin. . EXAMPLE 70 PROCEDURE: Charge 400 ml. (4 parts) of kraft black This example illustrates the separation of lignin from liquor (50% solids) into a one liter vessel. Add 100 kraft black liquor by using methyl amyl ketone, an or ml. (1 part) of water and stir. Then add 100 ml. (1 ganic ketone, a partial solvent for lignin. part) of dimethyl-4-heptanone. While this mixture is PROCEDURE: Charge 400 ml. (4 parts) of kraft black being stirred, add 25 ml. (0.25 parts) of 80% acetic liquor (50% solids) into a one liter vessel. Add 100. acid slowly over a five minute interval. As soon as the ml. (1 part) of water and stir. Then add 100 ml. (1 viscosity of the mixture starts to increase the stirring part) of methyl amyl ketone. While this mixture is 45 may be discontinued and a layer starts to form which being stirred, add 25 ml. (0.25 parts) of 80% acetic contains the lignin. acid slowly over a five minute interval. As soon as the viscosity of the mixture starts to increase the stirring EXAMPLE 75 may be discontinued and a layer starts to form. This example illustrates the separation of lignin from 50 kraft black liquor by using xylene solvent which con EXAMPLE 71 sists of a mixture of ortho and para xylene as well as : This example illustrates the separation of lignin from some ethyl benzene. This material is normally consid kraft black liquor by using Pluracol TP-740, a product ered to be a non-solvent for lignin. of BASF WYANDOTTE, a liquid polyoxypropylene PROCEDURE: Charge 400 ml. (4 parts) of kraft black derivative of trimethylolpropane. This material is nor 55 liquor (50% solids) into a one liter vessel. Add 100 mally considered to be only a partial solvent for lignin. ml. (1 part) of water and stir. Then add 100 ml. (1 This example also illustrates a very large market for part) of xylene. While this mixture is being stirred, lignin by combining lignin with various polyether poly add 25 ml. (0.25 parts) of 80% acetic acid slowly over ols to produce various polyurethane products. a five minute interval. As soon as the viscosity of the PROCEDURE: Charge 400 ml. (4 parts) of kraft black 60 mixture starts to increase the stirring may be discon liquor (50% solids) into a one liter vessel. Add 100 tinued and a layer starts to form which contains the ml. (1 part) of water and stir. Then add 100 ml. (1 lignin. part) of Pluracol TP-740. While this mixture is being stirred, add 25 ml. (0.25 parts) of 80% acetic acid EXAMPLE 76 slowly over a five minute interval. As soon as the 65 This example illustrates the separation of lignin from viscosity of the mixture starts to increase the stirring kraft black liquor by using ethyl benzene, an aromatic may be discontinued and a layer starts to form which hydrocarbon. This material is normally considered to contains the lignin. be a non-solvent for lignin. 4,265,809 29 30 PROCEDURE: Charge 400 ml. (4 parts) of kraft black stirred, add 50 ml. (0.5 parts) of concentrated sulfuric liquor (50% solids) into a one liter vessel. Add 100 acid slowly over a five minute interval. Once the ml. (1 part) of water and stir. Then add 100 ml. (1 addition of the sulfuric acid is complete, the stirring part) of ethyl benzene. While this mixture is being may be continued for another fifteen minutes and stirred, add 25 ml. (0.25 parts) of 80% acetic acid 5 then stopped. The length of time which is required at slowly over a five minute interval. As soon as the this point for stirring is dependent on the amounts of viscosity of the mixture starts to increase the stirring material involved in the separation. Once the stirring may be discontinued and a layer starts to form which is discontinued, a layer starts to form which contains contains the lignin. the lignin. EXAMPLE 77 10 EXAMPLE 81 This example illustrates the separation of lignin from kraft black liquor by using monochlorobenzene, an This example illustrates the separation of lignin from aromatic chlorohydrocarbon. This material is normally sulfite waste liquor by using a solvent such as benzalde considered to be a non-solvent for lignin, 15 hyde, an aromatic aldehyde. PROCEDURE: Charge 400 ml. (4 parts) of kraft black PROCEDURE: Charge 320 ml. (3.2 parts) of sulfite liquor (50% solids) into a one liter vessel. Add 100 waste liquor into a one liter vessel. Add 220 ml. (2.2 ml. (1 part) of water and stir. Then add 100 ml. (1 parts) of water and stir. Then add 200 ml. (2.0 parts) part) of monochlorobenzene. While this mixture is of benzaldehyde. While this mixture is being stirred, being stirred, add 25 ml. (0.25 parts) of 80% acetic 20 add 50 ml. (0.5 parts) of concentrated sulfuric acid acid slowly over a five minute interval. As soon as the slowly over a five minute interval. Once the addition viscosity of the mixture starts to increase the stirring of the sulfuric acid is complete, the stirring may be may be discontinued and a layer starts to form which continued for another fifteen minutes and then contains the lignin. stopped. The length of time which is required at this EXAMPLE 78 25 point for stirring is dependent on the amounts of This example illustrates the separation of lignin from material involved in the separation. Once the stirring kraft black liquor by using a number one fuel oil, which is discontinued, a layer starts to form which contains is an aliphatic hydrocarbon. This material is normally the lignin. considered to be a non-solvent for lignin. 30 EXAMPLE 82 PROCEDURE: Charge 400 ml. (4 parts) of kraft black liquor (50% solids) into a one liter vessel. Add 100 This example illustrates the separation of lignin from ml. (1 part) of water and stir. Then add 100 ml. (1 sulfite waste liquor by using mesityl oxide, an organic part) of number one fuel oil. While this mixture is ketone. This material is normally considered to be only being stirred, add 25 ml. (0.25 parts) of 80% acetic 35 a partial solvent for lignin. acid slowly over a five minute interval. As soon as the PROCEDURE: Charge 320 ml. (3.2 parts) of sulfite viscosity of the mixture starts to increase the stirring waste liquor into a one liter vessel. Add 220 ml. (2.2 may be discontinued and a layer starts to form which parts) of water and stir. Then add 200 ml. (2.0 parts) contains the lignin. of mesityl oxide. While this mixture is being stirred, add 50 ml. (0.5 parts) of concentrated sulfuric acid EXAMPLE 79 slowly over a five minute interval. Once the addition This example illustrates the separation of lignin from of the sulfuric acid is complete, the stirring may be kraft black liquor by using Freon TF, a duPont product, continued for another fifteen minutes and then which is a fluorocarbon. This material is normally con stopped. The length of time which is required at this sidered to be a non-solvent for lignin. The use of fluoro 45 point for stirring is dependent on the amounts of carbons have several advantages, the first is that they material involved in the separation. Once the stirring have low boiling points which requires less energy to is discontinued, a layer starts to form which contains spray-dry and they can easily be recovered and used the lignin. again. These types of materials also are non-flammable and relatively non-toxic. 50 EXAMPLE 83 PROCEDURE: Charge 400 ml. (4 parts) of kraft black liquor (50% solids) into a one liter vessel. Add 100 This example illustrates the separation of lignin from ml. (1 part) of water and stir. Then add 100 ml. (1 sulfite waste liquor by using butyraldehyde, an organic part) of Freon TF, a fluorocarbon. While this mixture aldehyde. This material is normally considered to be is being stirred, add 25 ml. (0.25 parts) of 80% acetic 55 only a partial solvent for lignin. acid slowly over a five minute interval. As soon as the PROCEDURE: Charge 320 ml. (3.2 parts) of sulfite viscosity of the mixture starts to increase the stirring waste liquor into a one liter vessel. Add 220 ml. (2.2 may be discontinued and a layer starts to form which parts) of water and stir. Then add 200 ml. (2.0 parts) contains the lignin. of butyraldehyde. While this mixture is being stirred, 60 add 50 ml. (0.5 parts) of concentrated sulfuric acid EXAMPLE 80 slowly over a five minute interval. Once the addition This example illustrates the separation of lignin from of the sulfuric acid is complete, the stirring may be sulfite waste liquor by using a solvent such as methyl continued for another fifteen minutes and then amyl ketone, an organic ketone. stopped. The length of time which is required at this PROCEDURE: Charge 320 ml. (3.2 parts) of sulfite 65 point for stirring is dependent on the amounts of waste liquor into a one liter vessel. Add 220 ml. (2.2 material involved in the separation. Once the stirring parts) of water and stir. Then add 200 ml. (2.0 parts) is discontinued, a layer starts to form which contains of methyl amyl ketone. While this mixture is being the lignin. 4,265,809 3. 32 resorted to without departing from the spirit and the EXAMPLE 84 scope of the invention as hereinafter claimed. This example illustrates the separation of lignin from What is claimed is: sulfite waste liquor by using a xylene solvent which 1. The method of producing unsaturated reactive end consists of a mixture of ortho and para xylene as well as groups on lignin obtained by contacting aqueous waste some ethyl benzene, which represent aromatic hydro black liquor from the kraft pulping process with an carbons. This material is normally considered to be a organic chemical solvent, and adding an acid to the non-solvent for lignin. mixture to lower the pH to thereby separate a layer PROCEDURE: Charge 320 ml. (3.2 parts) of sulfite which layer contains extracted or separated lignin in waste liquor into a one liter vessel. Add 220 ml. (2.2 10 said organic solvent separate from an aqueous layer, parts) of water and stir. Then add 200 ml. (2.0 parts) wherein such method comprises either reacting the said of a xylene solvent which consists of a mixture of separated layer of lignin in said organic solvent with a ortho and para xylene as well as some ethyl benzene. carbonyl compound containing active hydrogen and a While this mixture is being stirred, add 50 ml. (0.5 compound selected from the group consisting of alpha, parts) of concentrated sulfuric acid slowly over a five 15 beta-unsaturated carbonyl compounds and acryloni minute interval. Once the addition of the sulfuric acid trile, or reacting said lignin in said organic solvent with is complete, the stirring may be continued for another a compound selected from the group consisting of cya fifteen minutes and then stopped. The length of time noacetic acid, esters of cyanoacetic acid, malonic acid which is required at this point for stirring is depen and esters of malonic acid, to produce alpha, beta dent on the amounts of material involved in the sepa 20 unsaturated reactive end groups on said lignin which ration. Once the stirring is discontinued, a layer starts end groups are amenable to epoxidation. to form which contains the lignin. 2. The method of claim , wherein said reactive end EXAMPLE 85 groups are unsaturated carbonyl groups. 3. The method of claim , wherein said reactive end This example illustrates the separation of lignin from 25 groups are unsaturated nitrogen containing compounds. sulfite waste liquor by using a Freon TF, a duPont 4. The method of claim 2, wherein said reactive un product which is a fluorocarbon. This material is (con saturated carbonyl groups comprise aldehydes, ketones, tinuation of Example 85) normally considered to be a esters or acids. non-solvent for lignin. 5. The method of claim 3, wherein said reactive un PROCEDURE: Charge 320 ml. (3.2 parts) of sulfite 30 saturated nitrogen containing compounds comprise waste liquor into a one liter vessel. Add 220 ml. (2.2 nitriles or amides. parts) of water and stir. Then add 200 ml. (2.0 parts) 6. The method of claim , wherein the lignin contain of Freon TF, a fluorocarbon. While this mixture is ing alpha, beta-unsaturated reactive end groups is epoxi being stirred, add 50 ml. (0.5 parts) of concentrated 35 dized by the reaction with a peroxide. sulfuric acid slowly over a five minute interval. Once 7. The method of claim 1, wherein the lignin contain the addition of the sulfuric acid is complete, the stir ing alpha, beta-unsaturated reactive end groups is epoxi ring may be continued for another fifteen minutes and dized by the reaction with hydrogen peroxide or so then stopped. The length of time which is required at dium peroxide. this point for stirring is dependent on the amounts of 40 8. The method of claim 2, wherein the lignin contain material involved in the separation. Once the stirring ing alpha, beta-unsaturated carbonyl groups is epoxi is discontinued, a layer starts to form which contains dized by the reaction with a peroxide. the lignin. 9. The method of claim 2, wherein the lignin contain CONCLUSION ing alpha, beta-unsaturated reactive end groups is epoxi 45 dized by the reaction with hydrogen peroxide or so It will be apparent from the above that a new and dium peroxide. unique process has been disclosed for separating lignin 10. The method of claim 3, wherein the lignin con from waste black cooking liquor resulting from the taining alpha, beta-unsaturated nitrogen containing end kraft and sulfite paper pulping processes and then pro groups is epoxidized by the reaction with a peroxide. ducing an expoxide-lignin resin from the so separated 50 11. The method of claim 3, wherein the lignin con lignin. This resin is then susceptible of many uses in taining alpha, beta-unsaturated reactive end groups is cluding adhesives, paints and cast and hardened resin epoxidized by the reaction with hydrogen peroxide or ous or plastic products. This process therefore provides sodium peroxide. new use for lignin which has been previously used pri 12. The method of making a lignin-epoxide material marily only for its heat value by burning. It will be clear 55 comprising the steps of placing lignin in a liquid me from the present disclosure that lignin resulting from dium, reacting said lignin with a compound selected paper pulping processes in general may be utilized for from the group consisting of alpha, beta-unsaturated the disclosed purposes and it need not have been sepa carbonyl compounds, acrylonitrile, cyanoacetic acid, rated solely by the process first disclosed herein. The esters of cyanoacetic acid, malonic acid, and esters of lignin separated from the black liquors is also suscpeti 60 malonic acid, to produce alpha, beta-unsaturated end ble of many commercial uses. groups on the lignin molecules which end groups are Although this invention has been described in its selected from the group consisting of alpha, beta preferred form and preferred practice with a certain unsaturated carbonyl groups and alpha, beta degree of particularity, it is understood that the present unsaturated nitrogen containing compounds, and, there disclosure of the preferred form and preferred practice 65 after, converting the alpha, beta-unsaturated carbon has been made only by way of example and that numer carbon bonds of said unsaturated end groups to epox ous changes in the details of construction and the com ides, or oxirane compounds, by reaction with a perox bination and arrangement of parts and steps may be ide. 4,265,809 33 34 13. The method claimed in claim 12, wherein said selected from the group consisting of alpha, beta lignin is recovered from the waste black cooking liquor unsaturated carbonyl groups and alpha, beta from the kraft paper pulping process. unsaturated nitrogen-containing compounds, and there 14. The method claimed in claim 13, wherein said after converting the said alpha, beta-unsaturated car liquid medium is an aqueous medium or an organic bon-carbon bonds of said unsaturated end groups to solvent for said lignin. epoxides, or oxirane compounds, by reaction with ac 15. The method claimed in claim 14, wherein said tive oxygen agents. unsaturated carbonyl groups comprise aldehydes, ke 21. The method of making a lignin-epoxide material tones, esters or acids. comprising the steps of placing lignin in a liquid me 16. The method claimed in claim 14, wherein said 10 dium, reacting said lignin with a compound selected unsaturated nitrogen containing compounds comprise from the group consisting of alpha, beta-unsaturated nitriles or amides. carbonyl compounds, acrylonitrile, cyanoacetic acid, 17. The method claimed in claim 14, wherein said esters of cyanoacetic acid, malonic acid, and esters of peroxide is hydrogen peroxide or sodium peroxide. malonic acid, to produce alpha, beta-unsaturated end 18. The method claimed in claim 15, wherein said 15 groups on the lignin molecules which end groups are unsaturated carbonyl groups are produced by the reac selected from the group consisting of alpha, beta tion of mesityl oxide and formaldehyde with the lignin; unsaturated carbonyl groups and alpha, beta by the reaction of acrolein with the lignin; by the reac unsaturated nitrogen containing compounds, and there tion of malonic acid with the lignin; by the reaction of after converting the said alpha, beta-unsaturated car dimethylmalonate with lignin; or by the reaction of 20 bon-carbon bonds of said unsaturated end groups to diethylmalonate with the lignin. epoxides, or oxirane compounds, by reaction with hy 19. The method claimed in claim 16, wherein said drogen peroxide or sodium peroxide. unsaturated nitrogen containing compounds are pro 22. Lignin derivatives comprising lignins with alpha, duced by the reaction of acrylonitrile, cyanoacetic acid, beta-unsaturated carbonyl end groups thereon. ethyl cyanoacetic and methyl cyanoacetic. 25 23. Lignin derivatives comprising lignins with alpha, 20. The method of making a lignin-epoxide material beta-unsaturated nitrogen-containing end groups comprising the steps of placing lignin in a liquid me thereon. dium, reacting said lignin with a compound selected 24. Lignin-epoxide compounds comprising lignins from the group consisting of alpha, beta-unsaturated containing oxirane rings in end groups thereon, and in carbonyl compounds, acrylonitrile, cyanoacetic acid, 30 which said oxirane rings are the product of the peroxidi esters of cyanoacetic acid, malonic acid, and esters of zation of alpha, beta-unsaturated carbon-carbon bonds malonic acid, to produce alpha, beta-unsaturated end contained in said end groups. groups on the lignin molecules which end groups are sk is k 35

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