A method for the production of heavy metal bromine identical and, if necessary, hydrogen bromide from the destillationsrueckstand of the mother liquor after separation of the terephthalic acid in the case of the oxidation of p - dialkyl benz oils in flue polyethylene phase in the presence of heavy metal-containing, bromine activated oxidation catalysts and a lower aliphatic carbonsaeure resulting reaction mixture

摘要

1460941 Catalyst recovery MATSUYAMA PETROCHEMICALS Inc 26 March 1974 [30 March 1973 26 April 1973] 13234/74 Heading C1A [Also in Division C2] Co, Mn and Br catalyst components are recovered in a pure form from the mother liquor residue of the oxidation of an alkylbenzene to terephthalic acid in a lower monocarboxylic acid after removal of said acid by (a) stirring the mother liquor residue with water and a sulphur compound chosen from H 2 S, Na 2 S, NaHS, KHS, NH 4 HS while blowing or compressing a molecular O 2 -containing gas into it, thereby extracting the catalyst components, (B) separating the solid impurities so formed, (C) passing the catalyst containing extract through a column packed with a strongly-acidic cation-exchange resin to absorb the Co and/or Mn, (D) distilling the eluate collected up to the point at which the Co and/or Mn begin to pass out of the bottom of the column, whereby bromine is recovered as HBr, (E) passing HBr solution through the column to desorb the Co and /or Mn, (F) distilling the eluate thus obtained to recover excess HBr and a solution of the Co and/or Mn bromides in a pure state. In a modification of the process, when cobalt is necessarily present, the addition of sulphide material in step A is omitted and a further step of diluting the aqueous extract from step 3 to give a Co concentration of less than 1 wt. per cent before continuing with step C is carried out.