New insights into the extraction of invisible gold in a low-grade high-sulfur Carlin-type gold concentrate by bio-pretreatment  

作　　者：Xiao-bin Qiu Jian-kang Wen Song-tao Huang Hong-ying Yang Mei-lin Liu Biao Wu 

机构地区：[1]National Engineering Laboratory of Biohydrometallurgy, General Research Institute for Nonferrous Metals [2]School of Metallurgy, Northeastern University

出　　处：《International Journal of Minerals,Metallurgy and Materials》2017年第10期1104-1111,共8页矿物冶金与材料学报（英文版）

基　　金：financially supported by the National Science and Technology Supporting Program (No. 2012BAB10B08);the National High Technology Research and Development Program of China (No. 2012AA060501)

摘　　要：To extract gold from a low-grade(13.43 g/t) and high-sulfur(39.94wt% sulfide sulfur) Carlin-type gold concentrate from the Nibao deposit, Guizhou, a bio-pretreatment followed by carbon-in-pulp(CIP) cyanide leaching process was used. Various methods were used to detect the low-grade gold in the concentrate; however, only time-of-flight secondary-ion mass spectrometry(TOF-SIMS) was successful. With bio-pretreatment, the gold recovery rate increased by approximately 70.16% compared with that obtained by direct cyanide leaching of the concentrate. Various attempts were made to increase the final gold recovery rate. However, approximately 20wt% of the gold was non-extractable. To determine the nature of this non-extractable gold, mineralogy liberation analysis(MLA), formation of secondary product during the bio-pretreatment, and the preg-robbing capacity of the carbonaceous matter in the ore were investigated. The results indicated that at least four factors affected the gold recovery rate: gold occurrence, tight junctions of gold-bearing pyrite with gangue minerals, jarosite coating of the ore, and the carbonaceous matter content.To extract gold from a low-grade(13.43 g/t) and high-sulfur(39.94wt% sulfide sulfur) Carlin-type gold concentrate from the Nibao deposit, Guizhou, a bio-pretreatment followed by carbon-in-pulp(CIP) cyanide leaching process was used. Various methods were used to detect the low-grade gold in the concentrate; however, only time-of-flight secondary-ion mass spectrometry(TOF-SIMS) was successful. With bio-pretreatment, the gold recovery rate increased by approximately 70.16% compared with that obtained by direct cyanide leaching of the concentrate. Various attempts were made to increase the final gold recovery rate. However, approximately 20wt% of the gold was non-extractable. To determine the nature of this non-extractable gold, mineralogy liberation analysis(MLA), formation of secondary product during the bio-pretreatment, and the preg-robbing capacity of the carbonaceous matter in the ore were investigated. The results indicated that at least four factors affected the gold recovery rate: gold occurrence, tight junctions of gold-bearing pyrite with gangue minerals, jarosite coating of the ore, and the carbonaceous matter content.

关 键 词：GOLD ore invisible GOLD bio-pretreatment mineralogy LIBERATION analysis secondary product CARBONACEOUS matter 

分 类 号：TF831[冶金工程—有色金属冶金]