Method for reducing formation of polychlorinated aromatic compounds during air oxychlorination of c1-c3 hydrocarbons

摘要

An improved process is disclosed for manufacturing chlorinated hydrocarbon by way of a once-through air-based oxychlorination process which yields reduced levels of environmental toxins such as chlorobenzenes, polychlorinated biphenyls, polychlorinated dibenzodioxins and polychlorinated dibenzofurans. The process involves fixed bed or fluid bed catalyzed oxychlorination of a hydrocarbon reactant containing from 1 to 3 carbon atoms. The oxychlorination process consists of contacting the hydrocarbon reactant with air or oxygen enriched air and hydrogen chloride in the presence of the oxychlorination catalyst in a heated reaction zone operated at from 150 DEG C to 600 DEG C and recovering chlorinated hydrocarbon from the effluents of the reaction zone. The improvement consists of the use of air which is pretreated before use in the operated oxychlorination process by a means for removal of the aromatic hydrocarbons.