申请人:Allied Chemical Corporation
公开号:US04173708A1
公开(公告)日:1979-11-06
A process is described for purifying 4,4'-benzophenonedicarboxylic acid, useful in preparing thermoplastic polyesters yielding molded articles having high impact strength, wherein the acid contains aromatic monocarboxylic acid genetic impurity, which comprises the steps of (a) mixing the impure 4,4-benzophenonedicarboxylic acid with aqueous ammonium hydroxide solution, containing about 28 weight percent or less of ammonia in a weight ratio of solution to acid of about 5:1 to 100:1, thereby forming a solution of the diammonium salt of the aromatic dicarboxylic acid; (b) mixing the resultant solution with an inert water-soluble organic liquid which is a non-solvent for the diammonium salt, in a weight ratio of organic liquid to solution not greater than about 20:1, thereby precipitating the diammonium salt of the acid; (c) separating the diammonium salt from the solution; and (d) recovering the aromatic dicarboxylic acid from the diammonium salt.
本发明描述了一种用于纯化4,4'-苯二甲酸,该酸含有芳香基单羧酸杂质,用于制备热塑性聚酯,从而产生具有高冲击强度的成型制品的过程。该过程包括以下步骤:(a)将不纯的4,4-苯二甲酸与含有约28重量%或更少氨的氢氧化铵水溶液混合,溶液与酸的重量比为5:1至100:1,从而形成芳香二羧酸的二氨盐溶液;(b)将所得溶液与惰性水溶性有机液体混合,该液体是二氨盐的非溶剂,有机液体与溶液的重量比不大于20:1,从而沉淀出酸的二氨盐;(c)将二氨盐从溶液中分离;(d)从二氨盐中回收芳香二羧酸。