Microwave treatment for gold minerals used in small-scale mining

Abstract

Gold mining in Colombia has produced wealth that has helped the social and economic development of the country. Studying its extraction process offers artisanal mining broad alternatives that are more profitable for its small-scale production. Through this research, the possibility is offered of extracting 93.10% of gold in 180 minutes from a refractory mineral of pyritic origin with economic and environmentally friendly techniques such as the use of pretreatment with microwave waves, exposing the mineral to 637ºC for a maximum time of 4 minutes, and the use of thiourea as leaching agent at concentrations of 0.1 M. When comparing gold extraction with thiourea without pretreatment, a low extraction percentage is shown, 19.98%. This microwave pretreatment process was carried out on a nickeliferous laterite mineral, however, the results were not as effective for the extraction of nickel, only 40.8% was obtained in 420 minutes, because the pretreatment with its exposure Microwaving was not efficient.