US1280612A - Process of chlorinating toluene. - Google Patents

Description

UNITED STATES PATENT orricn.

CHAUNOEY O. LOOMIS, OF SYRACUSE, NEW YORK, ASSIGNOR '10 SEI MET-SOLVAY OOH- PAN'Y, OF SOLVAY, NEW YORK, A CORPORATION OF NEW YORK.

rnocnss or cnnoamarme TOLUENE.

No Drawing.

To all whom it may concern:

Be it known that I, GHAUNOEY C. LooMIs,

a citizen of the United States, residing at' Syracuse, in the county of Onondaga and State of New York, have invented a new and Improved Process of Chlorinatin Toluene, of which the following is a'speci cation.

My invention relates to the ChlOI'lIlEltlOn of toluene with consequent productlonv of benzyl chlorid and its related products, benzal chlorid and benzo trichlorid. This has heretofore been accomplished by passing chlorin gas throughboiling toluene and also by admitting to a mixture of toluene and bleachin powder an acid gas to decompose the leach with liberation of nascent chlorin. Both these processes are subject to objections, the former because of the difliculties incident to handling the chlorin and the production of by-products of little value which are not readily separable from the product desired and the latter by reason of the inconvenience of generating and. applying the acid gas and the gummin up caused by its reaction with the bleachlng powder in the toluene. I have discovered, however, and my invention broadly stated consists in the application of the fact, that by heating to a' high temperature an anhydrous mixture of toluene and bleaching powder, with thorough commingling, and without the use of any acid, the chlorination of the toluene is effected without any of the disadvantages incident to the processes above referred to. In the absence ofany added water the chlorin from the bleaching powder seems to go directly to produce benzyl chlorid in the side chain without attacking the nucleus, even though the process is carried on in the presence of iron, as in an iron vessel.

In carrying my invention into effect, dry bleaching powder (calcium hypochlorite, or

other equivalent hypochlorite,) and toluene are mixed-in proportions varying according to the extent of chlorination desired. For example, 200 kilograms of toluene are heated, as in asteam jacketed iron mixin kettle to a high temperature, sa 90 Dry bleachlng powder is then s owly added to this, the temperature being gradually raised untll 1t approximates the boiling point of Specification of Letters Patent.

Patented Oct. 1, 1918 Application filed October 18, 1917. Serial No. 197,205.

is effected, with continuous'thorough mixing. The escape of toluene vapor during the operation may be prevented by means of a reflux condenser fitted to the mixing vessel.

The resulting mixture is then cooled down and allowed to settle and as much oil as possible is siphoned off from the top. The oil left adhering to the line residue is then removed by steam distillation and added to that siphoned off. In this way 200 to 210 kilos of oil are obtained, having a specific gravity of .940 to .960 at 20 C. and containing from 30 to 35. per cent. of benzyl chlorid and from 70 to 65* per cent. of toluene. These can then be separated by fractional distillation. A higher percentage of chlorinated product can be obtained by using a greater proportion of the bleaching powder. In this case, however, some benzal chlorid and benzo trichlorid will be formed. Or, if desired, sufiicient bleaching powder may be added to convert all the toluene directly to benzal chlorid and benzo-trichlorid and'the resulting mixture of lime and the chloride can be converted into benzaldehyde and benzoic acid by boiling with water.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. The process of chlorinating toluene which consists in heating together an anhydrous mixture of toluene and bleaching powder without other admixture.

2. The process of chlorinating toluene which consists in heating together toluene andil dry bleaching powder in the absence of am 3. The process of chlorinating toluene which consists in heating together toluene and dry bleaching powder in the absence of acid or other agent for decomposing the OHAUNCEY C. LOOMIS.