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:
Nov. 24, 1987
Filed:
Jun. 28, 1985
Enzo L Coltrinari, Golden, CO (US);
Resource Technology Associates, Boulder, CO (US);
Abstract
A process is provided for removing cyanide from a dilute cyanide solution. The solution is passed through a weak base anion exchange resin to absorb cyanide complexes. The resin is eluted with a weakly basic Ca(OH).sub.2 solution, to produce a cyanide-rich eluate. Elution is accomplished by recycling the eluting fluid past a bed of solid Ca(OH).sub.2, to maintain the eluting fluid in Ca(OH).sub.2 saturation. Recycling in this manner produces an eluate with relatively high cyanide concentration using economical reagents. The eluate is subjected to an acidification/volatilization process including acidification, preferably with H.sub.2 SO.sub.4, heating by introduction of steam and removal of volatilized HCN by an air sparge. The HCN-rich off-gas and slats produced therefrom may be recycled in the process. The cyanide-depleted waste streams may be disposed of in, for example, tailings ponds.