GB353032A - Manufacture of alkyl chlorides or alkyl bromides from olefines or mixtures containing olefines - Google Patents

Abstract

Active carbon, used as a catalyst in the production of alkyl halides from olefines and hydrogen halides, is revivified by heating it to 300-1000 DEG C. in the presence of a controlled supply of steam.ALSO:Hydrochloric acid and/or hydrobromic acid is caused to combine with an olefine or olefines of low molecular weight in the presence of an adsorbent or a mixture of two or more adsorbents, which must be resistant to the action of the acid used. Suitable adsorbents are solids having a microporous structure and having the property of condensing gases e.g. partly or wholly dehydrated active carbon, including activated charcoal, partly or wholly dehydrated colloidal silica, and naturally occurring siliceous materials, which may have been dehydrated or extracted with acids, such as kieselguhr and "glaucosil." The reaction may be conducted at, above or below atmospheric pressure, and heat may be added or abstracted as desired. The reagents should be dried and may be introduced separately or together, and the olefines may be diluted with other substances, such as saturated hydrocarbons. Any residual saturated hydrocarbons may be treated with chlorine or bromine, the hydrogen halide formed being used for treating further quantities of olefines. The apparatus may be so arranged that the adsorbent may from time to time be removed or cut off from the sphere of reaction so that any product condensed thereon may be removed. Examples are given of the treatment of pure and diluted ethylene, propylene and butylene, and of pure amylene. The reaction temperatures specified are not above 120 DEG C. Specifications 209,722, 216,368, and 301,009 [all in Class 2 (iii), Dyes &c.], are referred to.