(1. 中南大學(xué) 資源加工與生物工程學(xué)院,長沙 410083;
2. 中南大學(xué) 生物冶金教育部重點實驗室,長沙 410083)
摘 要: 采用生物浸出和電化學(xué)測試,研究低溫10 ℃下AcidithiobacillusferrivoransYL15對黃銅礦和斑銅礦的協(xié)同浸出過程,結(jié)合不同的電化學(xué)測試手段探究其電化學(xué)溶解和表面鈍化行為。結(jié)果表明:不同礦物體系的生物浸出和電化學(xué)行為存在極大差異。協(xié)同浸出組的浸出率最高,達到了48.4%,斑銅礦的次之,且兩者都遠高于黃銅礦的16.4%。斑銅礦的加入降低了氧化還原電位并維持到一個適宜的范圍(400~420 mV),加快了礦物的氧化。另外,通過電化學(xué)測試,發(fā)現(xiàn)協(xié)同浸出組的電位降低、電流升高和阻抗減小、氧化速率大幅提高。
關(guān)鍵字: 黃銅礦;斑銅礦;協(xié)同浸出;低溫;電化學(xué);鈍化
(1. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Biometallurgy, Ministry of Education, Central South University, Changsha 410083, China)
Abstract:In this paper, the synergistic leaching process of chalcopyrite and bornite by Acidithiobacillus ferrivoransYL15 was studied at low temperature of 10 ℃. And its electrochemical dissolution and surface passivation behaviors were investigated by combining different electrochemical test methods. The results show that the bioleaching and electrochemical behavior of various mineral systems are extremely different. The optimal extraction rate of 48.4% in synergetic leaching group is obtained, followed by bornite, both of which are much higher than 16.4% of chalcopyrite. The redox potential is reduced and maintained to a suitable range (400-420 mV) as the addition of bornite to accelerate the oxidation of minerals. In addition, the electrochemical tests results indicate that the reduced potential, increased current and decreased impedance corporately reflect the significant increase of oxidation rate during synergistic leaching.
Key words: chalcopyrite; bornite; synergistic bioleaching; low temperature; electrochemical; passivation


