Patent · US Expired

Electrolytic sodium sulfate salt splitter comprising a polymeric ion conductor

US5928488A · kind A · utility

45Cited by
5References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 26, 1997
Grant dateJul 27, 1999
Priority date
Expiry dateAug 26, 2017

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08J2327/12
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The invention relates to an electrochemical process for the production of sodium hydroxide and sulfuric acid from aqueous sodium sulfate solutions, said process comprising the feeding of an aqueous sodium sulfate solution into a salt splitter device comprising at least three compartments including a middle feed compartment which is between an anode compartment and a cathode compartment, wherein the feed compartment is separated from the anode compartment by a chemically-functionalized anion exchange membrane, and wherein the feed compartment is separated from the cathode compartment by a chemically-functionalized cation exchange membrane. Specifically, the chemically-functionalized anion exchange membrane of the present invention is a perfluorohydrocarbon polymer material to which has been grafted a plurality of benzo-crown ether groups which have been complexed with a metal ion selected from sodium, potassium and lithium. Additionally, the chemically-functionalized cation exchange membrane is a perfluorohydrocarbon polymer material containing hydrolyzable ester groups, wherein said ester groups have been at least partially hydrolyzed to the carboxylic acid form.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.