Verfahren zur Oxychlorierung von Kohlenwasserstoffen und/oder deren partiell chlorierten Derivaten

摘要

(Un)satd. aliphatic hydrocarbons and benzene (opt. partly chlorinated) are oxychlorinated by reacting in a fixed or fluidised bed contg a catalyst with an active component consisting of chromium oxide activated with fluorinated inorganic compds., pref. an alkali metal fluorosilicate. Specif the catalyst conains 10-90% Cr and 0.3-1.5% alkali metal fluorosilicate together with silicon dioxide, kaolin and alkali metal silicates. The catalyst has a specific surface of 0.5-5 m2/g. The catalyst contains 0.5-5% ammonium dichromate which decomposes thermally to promote the formation of open pores. Unreacted gas is separated from the reaction product and recycled to the reactor. The catalyst is not volatile at elevated temps., and can be supplied continuously to the reactor during a prolonged time without loss of catalytic activity. The catalyst has a high catalytic activity and a high selectivity for chlorinated hydrocarbons, and a low oxidising action.