Patent · US Expired

Biological-acid leach process

US4571387A · kind A · utility

69Cited by
9References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 3, 1983
Grant dateFeb 18, 1986
Priority date
Expiry dateMar 3, 2003

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S423/17
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A process for leaching copper from copper sulphide containing ore, in particular copper from chalcopyrite containing ore, is provided. The ore is preferably initially ground up and mixed with an aqueous acid leaching medium containing sulphide oxidizing bacteria, and a bacterial nutrient, and a catalytic amount of silver. Provision is made in the bacterial nutrient for a source of carbon dioxide and oxygen for the bacteria, both of which may be supplied by means of sparging with carbon dioxide enriched air. A bacterial compatible acid is added initially to the ore and leaching medium mixture and periodically during the process so that sulphide in the copper sulphide is oxidized in stoichiometric amounts to elemental sulphur. During leaching the oxidation potential is maintained between about 0.54 to 0.66 volts, most readily by initial addition of thiosulphate and dissolved copper.

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