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. 13, 2001
Filed:
Jan. 22, 1999
David Bruce Dreisinger, Delta, British Columbia, CA;
Other;
Abstract
The invention provides a process for recovering hydrogen cyanide from an aqueous solution by extracting the hydrogen cyanide into an organic solvent phase. The organic solvent may comprise a neutral organophosphorous compounds, such as compounds selected from the group consisting of alkyl or aryl substituted phosphates, phosphonates and phosphine oxides. In alternative embodiments the organophosphorous compound is tri-butyl phosphate, di-butyl-butyl-phosphonate or tri-alkyl phosphine oxides. The organic solvent may be diluted in an organic diluent, such as an aliphatic or kerosene-type diluent. Alternative dilutions may be used, such as 75%, 50% or 25%. In some embodiments, the pH of the aqueous solution containing dissolved cyanide may be adjusted to between 2 and 8, or between 3 and 7, or between 4 and 6. The organic solvent may be contacted following extraction with a basic aqueous solution to strip cyanide from the organic solvent into a basic aqueous cyanide strip solution. The stripped organic solvent may then be returned to the loading process, to extract HCN from fresh aqueous solution.