GB667185A - Improvements in or relating to the production of ethyl chloride - Google Patents

Abstract

Ethyl chloride is prepared by passing a gaseous stream of between 1 and 10 volumes of ethane and 1 volume of chlorine into a reaction zone containing a bed of finely-divided inert solid heat transfer medium, at a temperature in the range 380 DEG to 440 DEG C. with a linear velocity sufficient to maintain the finely-divided solid material in suspension, removing the ethylene from the reaction gases by converting it to ethylene dichloride by passing the gaseous reaction products together with an amount of chlorine equal to the molar equivalent of the ethylene present through a subsidiary reactor maintained at a temperature not greater than 55 DEG C. and containing an additive chlorination catalyst comprising cupric chloride and active alumina, subsequently isolating the ethyl chloride and recycling the unreacted ethane. The reaction may be carried out at pressures up to 50 p.s.i. A suitable inert heat transfer material is sand consisting of particles of size 50-150 mesh. The exit gases from the main reactor consist of ethane, ethyl chloride, dichloroethanes, hydrogen chloride and ethylene. The gases are cooled and passed into the subsidiary reactor where the ethylene forms ethylene dichloride. Preferably an ethylene content of 5-10 per cent is maintained in the recycle gas. Ethyl chloride is removed from the exit gases from the subsidiary reactor, after the removal of hydrogen chloride and drying, by a suitable condensation system. An ethyl chloride content of not greater than 10 per cent (by volume) is maintained in the recycled gas. A small proportion of propylene may be present in the starting material and in that case allyl chloride, propylene dichloride and isopropyl chloride may be formed. Ethane, containing ethylene and possibly propylene, obtained by the cracking of petroleum hydrocarbons, is a suitable starting material. Oxygen should be excluded from the system as far as possible. Examples are given of the process in which different ratios of ethane to chlorine and different pressures are employed. Specification 639,435 is referred to.