Patented May 21, 1940 2,20,347

UNITED STATES PATENT OFFICE 2,201,34 IEETHOD FOR THE RANUFACTURE OF HY DROGENATION PRODUCTS OF FURRFUR.O, Wilheim Rittmeister, Dessati, Anhait, Ger many, assigno", by neSEe assignments, to “Patchem A.-G. Aur Beteiligtig An iPatenten Urd Sonstiger Erfindi. Yagsrechte: Auf (Caern ische Werfahren', Zurich, Switzerland, a cor poration of Switzerland No Drawi:2g. Application May 7, 193, Seria No. 14,306. in Gerina.ny November 4, 1936 6. Clairis. (CR. 260-345) It has been found that the hydrogenation of furfuryl alcohol will the hydrogenaticn of the nu furfurol, while in the vapor phase, to furfury cleus of this product to tetrahydro-furfuryl-al alcohol, tetrahydro-furfuryl-alcohol and to pen cChol begin, and then it starts in a most vigorous tandiols can be performed in a particularly Smooth 23ian her and often with Such violence that the manner and with nearly theoretical yields by heat of the reaction developed cannot be drawn conveying the furfurol in vapor phase over Solid off. With the result it leads to such high tempera catalysts together with a large excess of hydro tures that it causes the formation of undesirable gen or hydrogen-bearing gases at temperatures and sometimes even resin-like condensation prod lying above 100° C. and preferably between 130 licts. The exothermic heat of the process will O and 230° C. In the hydrogenation process it is under certain circunstances increase to an ex 10 preferable to use super-atmospheric pressure. pjosive intensity, so that the hydrogenation of fur Suitable pressures are those from 20 up to 500 furg in the liquid phase is, as stated in the prior atmospheres but preferably those from 20 to 250 art, rather dangerous especially if performed on atmospheres are employed. The quantity of hy a large Scale. Now those inconveniences are ab drogen found suitable for the process may be Solutely eliminated in applying the new method. 15. varied from 20 to 500 times the theoretically nec lvicreover it has been found that the catalysts essary amount. The excess of hydrogen is in any ealployed, When used in accordance with claimed case to be large enough to allow it to draw off methods, are more stable than in the liquid phase the very remarkable heat of the reaction devel hydrogenation process. In the latter case the effi 26 oped during the hydrogenation of the furfurol Ciency and Stability of the catalysts is diminished 20 without allowing an appreciable rise in the ten by the absorption of high molecular and some perature of the catalyst. ti) &S coke-like poly) aerization-products, where Among the different sorts of catalysts we may as With the claimed method such materials, which use anyone specified as being suitable for the fur inhibit, the hydrogenation, are formed either to 25 furol hydrogenation in the liquid phase Such as an insignificant degree or not at all. That is 25 nickel, nickel-chrome, nickel-copper, copper, Cop Why the consumption of catalysts is appreciably per-chrome, copper-zinc, cobalt, cobalt-chrone, reduced by the present invention, and even to cobalt-copper, cobalt-copper-chrome, nickel-cop a rairinurn, in using freshly distilled furfurol for per-chrome, nickel-copper-manganese, nickel the hydrogenation, which is always preferable. 30 30 copper-iron catalysts and the like, either in the Furthermore, it has been found that a dilution presence or in the absence of a carrier for the Cf the furful'ol with inert organic media and par catalyst. It may also be stated, that for the hy ticularly With alcohols Such as methanol, ethanol, drogenation according to the present method the isopropyl alcohol, butanol, tetrahydro-furfuryl catalysts need not be of the same high activity alcohol, throughout is of great advantage. Such as is necessary for the hydrogenation in the Eid 3, dilution, on the One hand, helps to take up 35 uid phase. We are therefore in a position to use and to dissipate the heat of the reaction during a simpler process of producing and reducing the the hydrogenation, while, on the other hand, it catalysts. Thus, for example a nickel-copper prevents the formation of polymerization and manganese carbonate catalyst, the power of cleavage products. In this Way the stability of which was insufficient for the hydrogenation of the catalystS is reinarkably enhanced, the output 40 furfurol in the liquid phase, proves most apt for of tetrahydro-furfuryl alcohol increased, due in the hydrogenation in the vapor phase. part to the fact that the formation of amyl alco Since the method claimed herein is continuous hol is considerably diminished. it offers all the well-known advantages of con Eacd32ple 1 45 tinuous hydrogenation as compared with discon tinuous methods. Within one hour 8 kilograms of freshly dis Beyond this the new method, compared with tilled furfuroi are conveyed over a nickel-copper the well-known procedures for the manufacture of tetrahydro-furfuryl alcohol and of pentandiols, ranganese catalyst together with 600 cubic shows the following considerable advantages: meters of hydrogen under a pressure of 200 at 50 When furfuro is hydrogenated in the liquid mospheres and at a temperature of 165-175° C. phase the reduction of aldehyde to alcohol, i. e., There is obtained 8.2 kilograms of a reaction to the furfuryl-alcohol, which is the first occur product consisting of 88% of tetrahydro furfuryl ring reaction, takes a comparatively slow course. . alcohol, 4% of anyl alcohol and 8% of 12 Only when nearly all furfurol is reduced to the and/or of 1,5-pentandiol. The reaction product 55 2 2,201,34? is suitable for use without further working-up as chrome, nickel-copper-chrome, nickel-copper a good Solvent or textile medium. manganese, nickel-copper-iron. Eacample 2 3. Method for the continuous manufacture of hydrogenation products of furfurol, characterized 5 kilograms of furfurol and 5 kilograms of by the hydrogenation of furfurol diluted with tetrahydro-furfuryl alcohol are conveyed over a inert Organic solvents of the group consisting of nickel-chrone catalyst together with 300 cubic methanol, ethanol, isopropyl alcohol, butanol, and meters of hydrogen under a pressure of 200 at tetrahydrofurfuryl alcohol and in the vapor mospheres and at a temperature of 150-160° C. phase at temperatures above 100° C. and under O The thus obtained product consists of 95% of tetrahydro-furfuryl alcohol, i9% of a mixture of a pressure of 20 to 500 atmospheres and with a 0. ainyl alcohol and 4% of 1,2 and 1,5-pentandiols, high exceSS of a hydrogen amounting to 20 to respectively. 500 times the theoretical amount necessary to Eacample 3 produce a major proportion of tetrahydrofurfuryl 5 alcohol in the presence of a hydrogenation cata 10 kilograms of freshly distilled furfurol are lyst. 5 conveyed over a copper-nickel-chrome catalyst 4. Method for the manufacture of hydrogena together with 1000 cubic meters of hydrogen un tion products of furfurol characterized by the hy der a pressure of 100 atmospheres and at a ten drogenation of furfurol in the vapor phase by re 20 perature of 200° C. The thus resulting reaction acting freshly distilled furfurol with hydrogen product contains 60% of tetrahydro-furfury al in the proportion of 8 kgS. of furfurol to 600 cohol, i8% of a mixture of amyl alcohol and cubic meters of hydrogen at a temperature of 30% of 1,2- and 1,5-pentandiols. 65 to 175° C. and under a pressure of 200 atmos I claim: phei'es in the presence of a nickel-copper-manga 1. Method for the continuous manufacture of nese catalyst to obtain tetrahydro furfuryl alco 25 hydrogenaticn products of furfurol comprising hol, amyl alcohol, and pentandiol. tetrahydrofurfuryl alcohol in a major proportion, 5. Method for the manufacture of hydrogena characterized by the hydrogenation of furfurol in tion products of furfurol characterized by the re the vapor phase attemperatures between 130 to action of 5 kgs. of furfurol diluted with 5 kgs. 230° C. and under a pressure of 20 to 500 atmos of tetrahydro-furfuryl alcohol with 300 cubic me 30 pheres and with an excess of hydrogen amounting ters of hydrogen at a temperature of 150 to 160° to 20 to 500 times the theoretical amount neces C. and under a pressure of 200 atmospheres in sary to produce said major proportion of tetra the presence of a nickel-chrome catalyst to ob hydrofurfuryl alcohol and in the presence of a tain tetrahydro-furfuryl alcohol, amyl alcohol, hydrogenation catalyst. and perstandiol. 35 2. Method for the continuous manufacture of 6. Method for the manufacture of hydrogena hydrogenation products of furfurol in the Vapor tion products of furfurol characterized by the phase, characterized by the hydrogenation of fur hydrogeiation of furfurol in the vapor phase by furol at temperatures above 100° C. and at pres reacting freshly distilled furfurol with hydrogen Sures between 20 to 500 atmospheres and with a 40 in the proportion of 10 kgs. of furfulrol to 1000 high excess of hydrogen announting to 20 to 500 cubic meters of hydrogen at a temperature of 40 times the theoretical amount necessary to pro 200° C. and under, a pressure of 100 atmospheres duce a major proportion of tetrahydrofurfuryl in the presence of a copper-nickel-chrome cata alcohol in the presence of a catalyst of the group lyst to obtain tetrahydro furfuryl alcohol, amyl 45 consisting of nickel, nickel-chrone, nickel-cop alcohol, and pentandiol. per, copper, copper-chrome, copper-zinc, cobalt, 45 cobalt-chrone, cobalt-copper, cobalt-copper WILHELMI RITTM ESTER CERTIFICATE OF CORRECTION. Patent No. 2, 201,57. May 21, 1940. WILHELM RITTMEISTER. It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, first column, lines ll and 21, strike out the words "a mixture of" and insert the same after "of" in lines l2 and 22 respectively; and that the said Letters Patent should be read with this correction there in that the same may con form to the record of the case in the Patent Office. Signed and sealed this 10th day of September, A. D. 1940.

(Seal) . Acting CommissionerLeslie Frazer, of Patents.