碳质金矿是一种重要的难处理金矿。研究发现,其碳质物主要包括元素碳、有机酸和烃类物质。在氰化浸金过程中碳质物可通过类活性炭的吸附方式将已溶解的金劫走。目前,已有的预处理方法主要有高温焙烧法、生物氧化法、化学氧化法、竞争吸附法、覆盖抑制法、微波加热法。生物氧化法因具有条件温和、流程简单、能耗低、环境友好等优点得以迅速发展。与生物氧化预处理有关的微生物主要有氧化亚铁硫杆菌、氧化硫硫杆菌、氧化亚铁钩端螺旋菌等化能无机自养菌。有关黄孢原毛平革菌、假单胞菌、多毛链霉菌在碳质物降解和钝化方面的研究也已展开。最后,分析了该技术存在的问题,并对其应用前景进行了展望。
Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanide complex is robbed by adsorption of carbonaceous matter, which is similar to activated carbon in cyanide leaching of gold. The pretreatment methods of carbonaceous gold ores were introduced, including high temperature roasting, bio-oxidation, chemical oxidation, competitive adsorption, barrier inhibition and microwave roasting. Recently, bio-oxidation was developed rapidly due to its advantages such as mild conditions, simple processes, low energy consumption and friendly environment. The known microorganisms related with bio-oxidation pretreatment mainly are chemolithotroph bacteria such as Thiobacillus ferrooxidans, Thiobacillus thiooxidans and Leptospirillum ferrooxidans. The researches on decomposing and passivating carbonaceous matter were commenced by Phanerochaete chrysosporium, Pseudomonadaceae and Streptomyces setonii. Finally, the main problems were analyzed and the application prospect of this technique was looked forward.