Method for generating and recycling copper chloride catalyst compositions for aromatic ring chlorination

摘要

A method for recovering and reusing a ring-halogenation catalyst comprises:
(A) Contacting an aromatic compound with chlorine or bromine in the presence of a catalyst composition, where the catalyst composition comprises at least one salt comprising a Group 4-13 metal, a lanthanide metal, or an actinide metal; and at least one organic counterion derived from an organic acid having a pKa relative to water of 0 or greater; and at least one organic sulfur compound; to form a first product mixture comprising a monochloro or a monobromo aromatic compound and a Group 4-13 metal halide, a lanthanide metal halide or an actinide metal halide;
(B) Separating the metal halide from the first product mixture; and
(C) Contacting at least a portion of the metal halide and an aromatic compound with chlorine or bromine, and at least one organic sulfur compound; to form a second product mixture comprising a monochloro or a monobromo aromatic compound and a Group 4-13 metal halide, a lanthanide metal halide or an actinide metal halide having a pKa relative to water of 0 or greater; and at least one organic sulfur compound.