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:
Mar. 27, 1979
Filed:
Dec. 27, 1977
Edward H Cook, Jr, Niagara Falls, NY (US);
Dirk Pouli, Williamsville, NY (US);
Hooker Chemicals & Plastics Corp., Niagara Falls, NY (US);
Abstract
A method for electrolytically producing a purified alkali metal hydroxide solution by electrolyzing an alkali halide solution in a membrane cell is described. The membrane cell includes at least one buffer compartment separating an anolyte and a catholyte compartment. The barrier separating the anolyte and the buffer compartment is a porous or permeable membrane. The membrane separating the catholyte compartment and the buffer compartment is a cation-active, hydrocarbon, preferably non-porous, membrane. A minor amount of a compound selected from the group consisting of alkali metal sulfites, bisulfites, sulfides, oxalates, or mixtures thereof, is added to the electrolyte, preferably with the brine feed, to protect the membranes from hypohalites formed in the cell. Amounts of protective compounds between about 0.01 and about 2.0 percent by weight of electrolyte are found to be aptly suited to use.