Trend of arsenic for the arsenic-containing gold ores or concentrates in the process of pretreatment

In recent years, the resources for free-milling gold ores have been nearly exhausted with the large-scale mining of gold deposits. Complex and refractory gold ores have become the main raw materials for gold production from ores in China's gold industry, such as arsenic-containing gold ores or concentrates. For arsenic-containing gold ores or concentrates, fine-grained gold is usually distributed in submicroscopic structures and encapsulated in sulfide minerals, such as pyrite and arsenopyrite, which means that gold recovery by leaching is extremely difficult without pretreatment. The pretreatment methods for arsenic-containing gold ores or concentrates include bio-oxidation, pressure oxidation, chemical oxidation, two-stage roasting, etc. In this paper, the trend of arsenic in the process of pretreatment is discussed by reviewing the basic mechanism and relevant research for the main pretreatment methods. In addition, future research directions on pretreatment methods are also proposed for arsenic-containing gold ores or concentrates.