GB853754A - Process for the production of chlorinated hydrocarbons - Google Patents

Abstract

Chlorinated aliphatic hydrocarbons are prepared by reacting at elevated temperatures in the gaseous state an aliphatic hydrocarbon containing 1-4 carbon atoms and/or a partially chlorinated derivative thereof with chlorine and/or hydrogen chloride and an oxygen-containing gas in a metal halide catalyst zone, continuously removing and analysing the product gases to determine the elemental oxygen content thereof, and adjusting the feed rates of the gases fed to the catalyst zone in response to the analysis so as to provide in the product gases an elemental oxygen content of 0,02-5% by volume. Partially chlorinated derivatives and non-chlorinated saturated and unsaturated hydrocarbons may be recycled. The oxygen-containing gas may be oxygen alone or with a diluent e.g. nitrogen, argon or neon, or air. Preferably 0,5-5 moles of chlorinating agent are supplied to the reactor per mole of hydrocarbon or partially chlorinated hydrocarbon, and 0,8-1,5 moles of oxygen per mole of chlorinating agent. Preferred catalysts are copper, chromium or iron halides, with or without, a halide of another metal, e.g. sodium or potassium, and may be impregnated on an inert carrier. The preferred reaction temperature is 350 DEG -700 DEG C. The adjustments to the feed rates may be made automatically in response to the analysis of the product gases.