Patent ID: 9505698
Filing Date: 2016-11-29
CPC Classification: B01D,C07C

Claim Text:
1. A process for recovering water, metals, soluble organics and insoluble organics in a mother liquor stream from the separation stage of a process for the production of a polycarboxylic acid, wherein the recovering process comprises: (a) cooling the stream to a temperature at which dissolved organics precipitate; (b) separating the precipitated organics from a liquid stream and recycling said organics to the process for the production of the polycarboxylic acid; (c) treating the liquid stream from step (b) with an alkali to convert remaining organics to the alkali salt form and the metals present to be converted to an insoluble form; (d) recovering the insoluble metals from a liquid stream; (e) passing the liquid stream from step (d) comprising the alkali salts of the organics to a membrane separation unit where it is separated into a permeate comprising water and a retentate comprising water and alkali organic salts; (f) recovering the permeate and recycling same to the process for the production of the polycarboxylic acid; and (g) recovering the retentate.