A process which comprises heating a reaction mixture comprised of an aqueous solution containing perchlorate ions, chlorate ions and hydrogen ions to produce chlorine dioxide and oxygen gas. The novel process of the present invention provides a commercially viable process for producing chlorine dioxide from mixtures of oxy-chlorine species in the absence of a reducing agent. The process can be operated without producing an acidic salt by-product while producing a chlorine dioxide product which is substantially free of chlorine. In addition, the process of the invention permits a reduction in the amount of acid fed to the chlorine dioxide generator.

Claims

23 · 3 independent · depth 4

23 granted claims

›1.independentA process for producing chlorine dioxide which comprises heating a reaction mixture comprising an aqueous solution containing perchlorate ions, chlora…+12

›2.↳ 1The process of claim 1 in which the concentration of hydrogen ions is at least 2 molar.d2

›3.↳ 1The process of claim 1 in which the chlorate ion concentration is at least 0.02 molar.d2

›4.↳ 1The process of claim 1 in which the concentration of the chlorate ion is from about 0.1 to about 3 molar.d2

›5.↳ 1The process of claim 1 in which the oxygen-evolving catalyst is a platinum group metal, a platinum group metal oxide, or mixtures thereof.d2

›6.↳ 1The process of claim 1 in which the molar ratio of perchlorate ions to chlorate ions is from about 0.5:1 to about 100:1.d2

›7.↳ 1The process of claim 1 in which the oxygen-evolving catalyst contains a metal from Group VIIIa of the Periodic Table of Elements.d2

›8.↳ 1The process of claim 1 in which the source of chlorate ions is a solution of chloric acid in a non-oxidizable inorganic acid.d2+2

›11.↳ 1The process of claim 1 in which the source of perchlorate ions is an aqueous solution of perchloric acid.d2

›12.↳ 1The process of claim 1 in which the reaction mixture is heated at a temperature in the range of from about 40.degree. to about 90.degree. C. at about …d2

›13.↳ 1The process of claim 1 in which the source of chlorate ions is a solution of chloric acid.d2

›14.independentA process which comprises heating a reaction mixture comprising an aqueous solution containing chloric acid and perchlorate ions in the presence of an…+6

›21.independentA process which comprises heating a reaction mixture consisting of essentially pure chloric and perchloric acids in the presence of ruthenium oxide to…+2

Classifications

2 codes

USPC · US Patent Classification

423/477423/478

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1.5 y

557 days filing → grant

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Examiner

Gary P. Straub

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