Patent ID: 7314954

Claim:
A method for recovering PTA (purified terephthalic acid) mother liquid and purifying and regenerating catalyst, said method includes following steps: a) said PTA mother liquid is filtered for separating solid organic materials from liquid; b) said liquid separated is heated, and is passed through a heat exchanger to raise its temperature for 5-10° C. to increase solubility of said organic materials in water; c) cobalt ions in said mother liquid are adsorbed with anion exchange resin till being saturated; d) said resin is regenerated with inorganic alkali, when there is organic material attached to surfaces of granules of said resin during exchanging of anion exchange resin, said inorganic alkali is used to regenerate said resin to remove said organic material on said surfaces; e) inorganic acid is used to take off by changing over all said cobalt ions adsorbed by said resin to form inorganic acid solution containing cobalt; and f) catalyst is purified and regenerated to convert said inorganic acid solution into metal cobalt which is then used to produce oxidized catalyst for a process of manufacturing (purified terephthalic acid) PTA, wherein said step to convert said inorganic acid solution into metal cobalt further includes steps: f-1) an acid solution step to resolve metal by adding inorganic acid solution; f-2) a neutralization and sedimentation step to adjust pH value to be 4 in order to eliminate iron ions and to form solution before extraction; f-3) a resin treatment step to use resin to remove copper, nickel and chromium ions in said solution before extraction in advance; f-4) a metal extraction step to use organic extractant to remove zinc and iron ions in said solution before extraction; and f-5) an electrolyzing step after extraction to obtain metal cobalt by electrolyzing said solution before extraction.