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United States Patent | 5,622,614 |
Keating ,   et al. | April 22, 1997 |
The present invention relates to an electrochemical cell and a process for using a halogen halide and splitting a sulfate solution and producing a hydroxide solution, sulfuric acid and a halogen gas. In particular, the sulfate solution may be an alkali metal sulfate solution, such as sodium or potassium sulfate solution, an alkaline earth metal sulfate solution or an ammonium sulfate solution. The cell and the process may use either an anhydrous or an aqueous hydrogen halide, namely, hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to a respective dry halogen gas, such as chlorine, fluorine, bromine, or iodine, to produce hydrogen ions in order to split the sulfate solution and form the sulfuric acid. The cell has two membrane-electrode assemblies, where an anode is disposed in contact with one membrane, and a cathode is disposed in contact with another membrane. The sulfate solution is fed in between the membrane-electrode assemblies.
Inventors: | Keating; Kenneth B. (Wilmington, DE); Trainham, III; James A. (Newark, DE); Law, Jr.; Clarence G. (West Trenton, NJ); Newman; John S. (Kensington, CA); Eames; Douglas J. (Chamblee, GA) |
Assignee: | E. I. Du Pont de Nemours and Company (Wilmington, DE) |
Appl. No.: | 431605 |
Filed: | May 1, 1995 |
Intern'l Class: | C25B 001/16 |
Field of Search: | 205/514,516,515,464,512,508,520,630 204/265,263 |
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______________________________________ Catalyst Reaction or Process ______________________________________ Cu Deacon Cu, Rare Earth, Alkali Shell-Chlor NO.sub.2, NOHSO.sub.4 Kel-Chlor Cr.sub.m O.sub.n MT-Chlor ______________________________________