Patent · US Expired

Methods of decontaminating substates with in-situ generated cyanides

US5678231A · kind A · utility

7Cited by
5References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 9, 1996
Grant dateOct 14, 1997
Priority date
Expiry dateJul 9, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/20
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Solid and liquid substrates, such as soil and solvents having radioactive metals or hazardous non-radioactive metals are decontaminated with the aid of cyanide ion generated in-situ to form co-ordination compounds with the unwanted metal contaminants. Cyanides are prepared by introducing into an ammoniacal liquid-containing slurry of a contaminated soil, or other solid or liquid substrate, a refrigerant compound, such as a hydrochlorofluorocarbon which produces ammonium cyanide, which in-turn forms a complex with the hazardous metal contaminant for separation with the ammoniacal liquid. The process may also utilize solvated electrons to at least partially dehalogenate a perhalogenated refrigerant like diclorodifluoromethane (R-12). Process avoids exposure to potentially hazardous cyanides through in-situ generation, while simultaneously destroying unwanted refrigerants which are potentially harmful to Earth's ozone layer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.