GB979309A - Process for the manufacture of vinyl chloride by the catalytic splitting of 1:2-dichlorethane - Google Patents

Abstract

Vinyl chloride is prepared by the catalytic splitting of 1, 2-dichloroethane in the presence of a solid catalyst at a temperature of 230 to 350 DEG C., the concentration of vinyl chloride in the reaction mixture not exceeding 40% by volume, the pressure not exceeding 2.5 atmospheres absolute, and the partial pressure of vinyl chloride in the reaction mixture not exceeding 0.5 atmospheres absolute. The concentration of vinyl chloride may be maintained at or below 40% by keeping the degree of conversion below 80% or by means of a diluent such as hydrogen chloride, an inert gas or a chlorinated hydrocarbon which will itself decompose to form hydrogen chloride. Suitable catalysts include non-impregnated or impregnated surface-active substances such as active carbon, silica gel, aluminium silicate or silicon carbide, active carbon impregnated with BaCl2 being used in examples. Fixed or fluidized beds may be used. Sub-atmospheric, atmospheric or super-atmospheric pressures are operable. The operating temperature may be raised by e.g. 1-2 DEG C. per week to maintain catalyst activity.ALSO:Catalysts for the thermal splitting of 1,2-dichloroethane to vinyl chloride: Example (2) active carbon particles 4 mm. in size impregnated under pressure with a concentrated solution of BaCl2 and then activated by a brief soaking in water; (3) active carbon particles 4 mm. in size (prepared from peat) impregnated with 30% by weight of BaCl2.