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. 07, 1995
Filed:
May. 24, 1993
Bernd Scharbert, Frankfurt am Main, DE;
Pierre Babusiaux, Lillebonne, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
The present invention describes a process for preparing glyoxylic acid by electrochemical reduction of oxalic acid in aqueous solution in divided or undivided electrolytic cells, wherein the cathode comprises from 50 to 99.999% by weight of lead and the aqueous electrolysis solution in the undivided cells or in the cathode compartment of the divided cells in addition contains at least one salt of metals having a hydrogen overpotential of at least 0.25 V, based on a current density of 2500 A/m.sup.2, and a mineral acid or organic acid. The process according to the invention has the advantage that a highly pure, expensive lead cathode can be dispensed with and industrially available lead-containing materials can be used, for example alloys which, in addition to lead, comprise at least one of the metals V, Sb, Ca, Sn, Ag, Ni, As, Cd and Cu. Periodic rinsing with nitric acid can be dispensed with.