Patent ID: 6756462
Filing Date: 2004-06-29
Classification: B01J,C08F,C08J

Abstract:
A method for preparing anion exchange resins in a multi-batch process, comprising:(i) in a first chloromethylation reaction, the steps of: (a) chloromethylating a first crosslinked poly(vinylaromatic) copolymer in the presence of sulfuric acid to provide a mixture of a first chloromethylated intermediate and sulfuric acid; (b) quenching the first chloromethylated intermediate to provide a quenched first chloromethylated intermediate by a non-agitated plug-flow downward addition of a quench solution to the mixture of first chloromethylated intermediate and sulfuric acid to obtain a first mother liquor effluent comprising 30 to 90% sulfuric acid; and (c) isolating the first mother liquor effluent for reuse in one or more subsequent chloromethylation reactions; and (ii) in a second chloromethylation reaction, the steps of: (aâ€²) chloromethylating a second crosslinked poly(vinylaromatic) copolymer in the presence of sulfuric acid and a portion of mother liquor effluent obtained from a prior chloromethylation-quench reaction sequence to provide a mixture of a second chloromethylated intermediate and sulfuric acid; (bâ€²) quenching the second chloromethylated intermediate to provide a quenched second chloromethylated intermediate by a non-agitated plug-flow downward addition of a quench solution to the mixture of second chloromethylated intermediate and sulfuric acid to obtain a second mother liquor effluent comprising 30 to 90% sulfuric acid; and (câ€²) isolating the second mother liquor effluent for reuse in one or more subsequent chloromethylation reactions.