The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 02, 1993
Filed:
Mar. 20, 1991
Wolfgang Habermann, Mainz, DE;
Werner Bochnitschek, Ludwigshafen, DE;
Johann Fritzmann, Heidelberg, DE;
Peter Hammes, Ruppertsberg, DE;
Theo Proll, Bad Durkheim, DE;
Walter Weisbrodt, Deidesheim, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
Alkali metal sulfates are electrolyzed to more concentrated solutions of alkali metal hydroxide and sulfuric acid by using a three-compartment electrodialysis cell at temperatures of .gtoreq.70.degree. to .gtoreq.150.degree. C. and current densities of from 0.5 to 15 kA/m.sup.2 using an anion exchange membrane whose polymeric ion exchange matrix comprises a styrene/divinylbenzene copolymer containing very strongly basic quaternary ammonium groups and a hydronium ion blocker, on whose central compartment side is an ion exchange layer or membrane containing tertiary or secondary amino groups.