42221
Accession Number
32827
Author
Geoffroy, Nicolas;Cardarelli, Francois
Title Of Article Chaper
A Method for Leaching or Dissolving Gold from Ores or Precious Metal Scrap
Title Of Journal Book
JOM
Pages
47-50
Collation
4 p. : ills.
Reference Bibliography
Includes bibliographic references
Language Of Text
English
Literature Type
Serial
Literature Level
Analytic
Abstract
The hydrometallurgical leaching of native gold from gold-bearing ores or the dissolution of gold metal during the recycling of electronic and metal scrap is performed every day using hazardous chemicals such as sodium cyanide or aqua regia. These chemicals represent health and safety risks for workers and a serious threat for the environment. However, even if several other reagents are known to dissolve gold at the laboratory scale, none of these are used industrially. Hot mixtures of hydrochloric acid with strong oxidizing compounds are known to generate in-situ nascent chlorine which is capable of dissolving gold efficiently. In this study, the authors investigated the capability of a hot mixture of hydrochloric acid and ground manganese (IV) oxide to dissolve gold metal either under atmospheric or pressurized conditions. The best result was obtained under a pressure of 639 kPa at 90[degree]C with a dissolution rate of 0.250 g[middle dot]cm-1h-1 and it was compared to that reported in the literature for other industrial reagents.
Keywords
leach;dissolve;method;gold;ore;precious;metal;scrap
pub_id
42221