Thiosulphate Leaching of Silver Sulphide Ore in Cupric Medium

Most silver ore is present in form of silver sulphide in nature. Traditional method of silver leaching treats the ore using cyanide, similar to gold leaching. Cyanide leaching has raised more public concerns in the society, due to its potential hazard toward human as well as environment. Regions start to regulate or ban the usage of cyanide leaching worldwide, so alternative to cyanidation becomes essential. Thiosulphate leaching has been by far the most successful alternative, due to its low toxicity, low cost and relatively high efficiency among all options. However, application of thiosulphate leaching is limited due to high reagent consumption and lower efficiency compared to cyanidation. The research project aims to improve the efficiency and decrease the reagent consumption of the system with additives, and provide a guideline for future research. The project is hoped to assist thiosulphate leaching to be more economically-viable, so the greener industrial process can gain a wider acknowledgement in future.

Faculty Supervisor:

David Dreisinger

Student:

Yueh (Yves) Lai

Partner:

Pan American Silver Corp.

Discipline:

Engineering

Sector:

Mining and quarrying

University:

University of British Columbia