Patented Feb. 20, 1951 2,542,216

UNITED STATES PATENT of FICE 2,542,216. STABLIZATION OF BENZY CHORDE. Erwin G. Somogyi, Springfield, Mass., assignor to . Monsanto Chemical Company, St. Louis, Mo, a corporation of Delaware. No Drawing. Application May 3, 1948, Serial No. 24,920 2 Claims. (C. 260-651) This invention relates to the stabilization of 2 benzyl chloride, and more particularly, to novel or iron Salts. For example, 450 pounds of benzyl. compositions comprising benzyl chloride, and a chloride mixed with 23 pounds of a 10% aqueous. stabilizer therefor. Sodium carbonate solution may be safely shipped Benzyl chloride is a widely used intermediate in a 55-gallon black iron drum. This wet sta in the production of benzyl derivatives, such bilized material is a milky-white emulsion, from as benzyl alcohol, benzyl benzoate, benzyl cel which a Water layer may separate upon stand lulose, benzyl acetate and the alkyl benzyl ing. However, before use, the benzyl chloride phthalates, and such benzyl derivatives find Wide must be recovered from the stabilized solutions, application as pharmaceuticals, plasticizers, rub as anhydrous liquid benzyl chloride is preferred 10, !. and necessary for most operations. Therefore, ber chemicals, gasoline gum inhibitors, dyestuffs at the present time, a user...of benzyl chloride and perfume bases. must either recover benzyl chloride from the so A serious disadvantage in the use of benzyl dium carbonate stabilized aqueous solution, or chloride lies in the fact that benzyl chloride is accept the risk of decomposition due to contam extremely unstable, oftentimes - violently un 5 ination of the anhydrous liquid benzyl chloride. stable, in the presence of iron, iron oxides or iron Shipped in nickel drums. salts. Those who are familiar with the handling It is an object of this invention, therefore, and use of benzyl chloride recognize that infinite to provide benzyl chloride stabilized against de and painstaking care must be exercised in the composition due to contamination by iron, rust. handling of benzyl chloride, as the slightest con 20 or iron salts. A further object of this invention. tamination, such as a flick of rust in a drum is to provide anhydrous benzyl chloride sta of benzyl chloride, will result in decomposition bilized against decomposition due to accidental and darkening of the benzyl chloride with an contamination by iron, rust, or iron salts. A still accompanying evolution of hydrogen chloride. further object, is to provide novel compositions The entire drum of benzyl chloride is then un 25 comprising benzyl chloride and a stabilizer: to fit for manufacturing uses and furthermore, the prevent decomposition due to accidental contam contaminated benzyl chloride is generally not ination by iron, rust or iron salts. recoyerable. Manufacturers of benzyl chloride, I have discovered that benzyl chloride con particularly anhydrous benzyl chloride take taining 0.05% to 2% of cyclohexanol is effec great care to insure that benzyl chloride is pack tively Stabilized against decomposition due to aged in clean nickel drums or nickel-lined con contamination by iron, rust or iron salts. In the tainers. However, in spite of all precautions, practice of this invention, a preferred stabilized should a speck of rust get into a container of benzyl chloride composition consists of benzyl benzyl chloride and the container be then sealed, chloride and 0.25% of cyclohexanol, and a pre the speck of rust will incite the decomposition 35 ferred range of compositions consists of benzyl of the benzyl chloride and the hydrogen chloride chloride and 0.1% to 0.5% of cyclohexanol. Such evolved due to the decomposition will generate compositions are effectively stabilized against de sufficient pressure to cause rupture of the con composition due to contamination by iron, rust tainers, particularly drums. This presents an or iron salts under most of the temperature con undesirable aspect for the reason that, not only ditions encountered in the handling, storager and is the benzyl chloride rendered unfit and lost for transportation of benzyl chloride. Moreover, manufacturing purposes, but the spilled liquid benzyl chloride thus stabilized with 0.1% to 0.5% benzyl chloride is irritating to the skin and the of cyclohexanol is not changed in appearance, benzyl chloride vapors are highly irritating to the physical and chemical properties of the the eyes. benzyl chloride are not appreciably effected and A large amount of effort has been expended to benzyl chloride thus stabilized may be used in try to stabilize benzyl chloride to prevent, de manufacturing processes in the same manner as composition of the benzyl, chloride in the event unstabilized benzyl chloride without the necessity. that the material is accidently contalminated of removing the stabilizing agent prior to ther withiron, rust or iron salts. Benzyl chloride is use of the benzyl chloride. . . presently stabilized with a 10% aqueous sodium The following examples are illustrative of the carbonate solution. ... Benzyl chloride thus sta method by which this invention may be prac bilized may be then safely shipped in black iron ticed, however, it is not intended that this in drums without danger of decomposition in the vention be limited Solely to the methods and com event of accidental contamination with iron, rust positions as Set forth in the following examples:

2,542,216 3 4. Eacample I tions generally encountered during storage and transportation operations, that is, under tem Two 55-gallon nickel drums containing an peratures varying between 68° F. and 95° F. hydrous benzyl chloride were obtained from a The Specifications for benzyl chloride which is commercial manufacturing proceSS. These used in commercial operations usually require drums were carefully opened and a composite that the material distill within the temperature sample of the two drums obtained. 0.5% of range of 177.5° C. to 185.0° C. Uncontainiinated cyclohexanol was added to drum No. 1 and 0.10% benzyl chloride will very readily distill with a of cyclohexanol was added to drum No. 2. About good 96% recovery and the test distillation may a cup full of rusty iron scrapings were added to 10 be effected with a clean “dry point' within these each of the drums and 2. The drums were temperature specifications. However, the dis then sealed by connecting them to a preSSure tillation of a sample which has been contami manometer to indicate any pressure changeS nated with iron results in a dark brownish Within the drum. As was pointed out herein viscous nondistillable residue which will not dis before, decomposition of benzyl chloride due to 5 till up to a temperature above 200° C. and the rust (iron) contamination is evidenced by an heating of which is evidenced by much Smoke abnormal evolution of hydrogen chloride gas. and the evident thermal decomposition. The pressure generated within a contaminated Bearing these facts in mind, the composites drum is often large enough to rupture the ends Sample of the benzyl chloride from drums A and of the drum. However, after six weeks storage 20 B, which were carefully preserved from con under generally encountered temperature condi tamination with iron, was distilled, the first drop tions of 20°-35° C. (68°-95° F.), the above drums of the composite sample coming over at 179.0° C. 1 and 2 evidenced no abnormal gas generation. and with a “dry point' of 183.9° C. Samples of . The composite sample obtained from drums 1 the benzyl chloride from drums A and B were and 2, prior to stabilization, was tested in the each washed with hydrochloric acid to remove laboratory by adding a few specks of the rusty any remaining traces of iron from the benzyl iron scrapings to the composite sample. The chloride. In view of the fact that the benzyl sample was completely decomposed into a dark chloride decomposition products are not soluble brown viscous material in two days. in hydrochloric acid, this wash would not re 30 move any decomposition material which might Eacample II have been present in the stabilized samples. The A sample of anhydrous benzyl chloride was hydrochloric washed Samples from drums A and taken from the production of a commercial B which had been stabilized. With cyclohexanol, process. This sample was divided into two por contaminated with rust and held under storage tions in the laboratory and to the one portion conditions for 52-days were then distilled; the was added 0.25% of cyclohexanol as a stabilizing 35 sample from drum. A containing 0.05% cyclo agent. When iron rust scrapings were added to hexanol distilled with a first drop at a tempera the unstabilized material, the decomposition re ture of 178.9° C. and a clean “dry point' of 183.0°. action had set in in about fifty minutes. The C. The Sample of benzyl chloride fron drum B reaction became quite violent, accompanied by a 40 containing the 0.10% cyclohexanol was distilled vigorous evolution of hydrogen chloride gas and with a first drop of 79.0° C. and with a clean the material became dark blackish brown in “dry point' of 183.0° C. color. The portion of the benzyl chloride Sample The preceding results are consistent within stabilized with 0.25% of cyclohexanol showed no the range of experimental error and showed reaction when contaminated with iron rust 45 definitely that there was no decomposition of the scrapings and storage for three months at room benzyl chloride during the test period. temperature of 20-30° C. Having described and set forth my invention Eacample III in detail and having given examples showing ma-. The decomposition of benzyl chloride is in terial improvement of my process over the prior it) art, stantaneous and extremely violent when benzyl I claim: chloride is contaminated with ferric chloride, 1. A composition of matter comprising benzyl however, the addition of 0.5% of cyclohexanol to chloride and 0.05% to 2% of cyclohexanol. a sample of benzyl chloride will effectively sta 2. A composition of matter comprising benzyl bilize benzyl chloride even against contamina tion by ferric chloride. When ferric chloride is chloride and 0.1% to 0.5% of cyclohexanol. added to benzyl chloride containing 0.5% cyclo ERWIN G. SOMOGYI. hexanol there appears to be instantaneous imme diate reaction, however, this reaction appears to REFERENCES CTED stop almost as quickly as it starts and the de The following references are of record in the composition of the benzyl chloride appears to be 60 file of this patent: thereafter completely inhibited. UNITED STATES PATENTS Eacample IV Number Nane - Date Two 55-gallion nickel drums containing an 2,043,257 Missbach ------June 9, 1936 hydrous benzyl chloride were obtained from a 65 2,136,333 Coleman et al. ------Nov. 8, 1938 commercial manufacturing process. These 2,160,944 Coleman et al. ------June 6, 1939 drums were carefully opened and a composite 2,355,319 Morris et al. ------Aug. 8, 1944 sample of the two drums obtained. 0.05% cyclo 2,371,644 Petering et al. --- Mar. 20, 1945 hexanol was added to drum A and 0.10% of 2,407,149 Gardenier ------Sept. 3, 1946 cyclohexanol was added to drum B. Rusty iron 70 2,435,887 Hornbacher et al. Feb. 10, 1948 scrapings were added to each of the drums A and B. The drums were then sealed by connect FOREIGN PATENTS ing them to a pressure manometer to indicate any pressure changes within the drum. The Number Country Date drums were then stored for 52 days under condi 5 794,653 France ------Feb. 22, 1936