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:
Jun. 30, 1992
Filed:
Mar. 13, 1991
Kenneth J Stutts, Midland, MI (US);
Mou S Chao, Midland, MI (US);
Ramanathan Gopal, Sarnia, CA;
Indresh Mathur, Sarnia, CA;
The Dow Chemical Company, Midland, MI (US);
Abstract
A method of producing sodium dithionite comprising electrolyzing a catholyte solution of sulfur dioxide in an electrolytic cell at a pH of at least about 3, the electrolytic cell having a carbonaceous cathode, is disclosed. Particularly high current efficiencies can be attained using a high surface area carbon material for the cathode. The use of a stabilizer to inhibit decomposition of the sodium dithionite to form sodium thiosulfate is also disclosed. The stabilizer is added to the catholyte and is selected from the group consisting of phosphoric acid, sodium tripolyphosphate, acid phosphates and mixtures thereof.