中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 30 No. 2 February 2020 |
（1. Institute of Mining Engineering, Inner Mongolia University of Science and Technology, Baotou 014010, China;
2. Guangdong Institute of Resources Comprehensive Utilization, Guangzhou 510650, China;
3. State Key Laboratory of Rare Metals Separation and Comprehensive Utilization, Guangzhou 510650, China;
4. Institute of Multipurpose Utilization of Mineral Resources, Chinese Academy of Geological Science, Chengdu 610041, China）
Abstract:The mechanism of sodium sulfide (Na2S) on the flotation of cyanide-depressed pyrite using potassium amyl xanthate (PAX) as collector was investigated by flotation test and electrochemical measurements. The flotation results show that both PAX and Na2S can promote the flotation recovery of cyanide-depressed pyrite and their combination can further improve the pyrite flotation recovery. Electrochemical measurements show that PAX and Na2S interacted with cyanide-depressed pyrite through different mechanisms. PAX competed with cyanide and was adsorbed on the pyrite surface in the form of dixanthogen, thus enhancing the hydrophobicity and flotation of cyanide-depressed pyrite. Unlike PAX, Na2S rendered the pyrite surface hydrophobic through the reduction of ferricyanide species and the formation of elemental sulfur S0 and polysulfide . The combined application of PAX and Na2S induced superior pyrite flotation recovery because of a synergistic effect between PAX and Na2S.
Key words: pyrite; chalcocite; flotation; cyanide; depression; sodium sulfide
