Patent ID: 7863209

Claim:
A method for recovering and reusing a ring-halogenation catalyst, said method comprising: (A) contacting an aromatic compound with chlorine or bromine in the presence of a catalyst composition, said catalyst composition comprising at least one salt comprising copper and at least one organic counterion derived from an organic acid having a pKa relative to water of 0 or greater and selected from the group consisting of a dicarboxylic acid, a 2,4-dione, and derivatives of the foregoing acids; and at least one organic sulfur compound; to form a first product mixture comprising copper chloride and a monochloro aromatic compound; (B) separating copper chloride from said first product mixture, and (C) contacting at least a portion of the separated copper chloride and an aromatic compound with chlorine, and at least one organic sulfur compound; to form a second product mixture comprising copper chloride and a monochloro aromatic compound.