Method for activation of aluminum chloride complex alkylation catalyst

In a method for the nuclear alkylation of an aromatic hydrocarbon compound in which said aromatic hydrocarbon compound is reacted with an alkyl halide in the presence of a catalytic amount of an aluminum chloride-aromatic hydrocarbon compound complex under reaction conditions which cause nuclear substitution in said aromatic hydrocarbon compound by an alkyl radical to be effected, the improvement which comprises:

• A. separating the aluminum chloride-aromatic hydrocarbon compound complex from the reaction mixture resulting from said nuclear alkylation of an aromatic hydrocarbon compound, and
• B. regenerating said aluminum chloride-aromatic hydrocarbon compound complex by washing at least part of it with a straight chain paraffinic hydrocarbon of 5- 24 carbon atoms which is liquid under the washing conditions and in an amount of at least 0.1 part by volume of said paraffinic hydrocarbon per 1 part by volume of aluminum chloride-aromatic hydrocarbon complex to permit the subsequent formation of two separate layers, the lower layer consisting solely of the regenerated aluminum chloride-aromatic hydrocarbon compound complex, said washing being conducted in a temperature range in which isomerization of said paraffinic hydrocarbon will not be effected, separating said lower layer of regenerated aluminum chloride-aromatic hydrocarbon complex and recycling said regenerated catalyst to said alkylation reaction.