(1. 中南大學 化學化工學院，長沙 410083；
2. 長沙理工大學 化學與生物工程學院，長沙 410114；
3. 中南大學 有色金屬資源化學教育部重點實驗室，長沙 410083)
摘 要: 為探明黃鐵礦在砷黃鐵礦生物浸出過程中的作用與影響，選擇純黃鐵礦和砷黃鐵礦組成的礦漿浸出體系，考察黃鐵礦和砷黃鐵礦質(zhì)量比以及黃鐵礦粒度對體系中砷的浸出率以及砷的氧化狀態(tài)的影響。結(jié)果表明：砷的浸出率隨黃鐵礦與砷黃鐵礦質(zhì)量比的增加而升高，隨黃鐵礦粒度的增加而減少。當黃鐵礦的粒度小于74 μm、黃鐵礦與砷黃鐵礦質(zhì)量比為10:2時，砷的最高浸出率為97.7%，比不添加黃鐵礦時砷的浸出率提高了約43.18%。且黃鐵礦可以加速As(Ⅲ)轉(zhuǎn)化為As(Ⅴ)，降低礦漿對細菌的毒害，使生物浸出體系細菌密度提高、pH下降、氧化還原電位φh升高并與砷黃鐵礦形成原電池效應(yīng)，從而促進砷黃鐵礦的浸出。
關(guān)鍵字: 黃鐵礦；砷黃鐵礦；氧化亞鐵硫桿菌；生物浸出；原電池效應(yīng)
（1. College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;
2. College of Chemistry and Biological Engineering, Changsha University of Science and Technology,
Changsha 410114, China;
3. Key Laboratory of Resources Chemical of Nonferrous Metals, Ministry of Education,
Central South University, Changsha 410083, China）
Abstract:In order to clarify the function of pyrite in arsenopyrite bioleaching, pure pyrite and arsenopyrite were used to prepare a pulp system for studying the effect of the pyrite-to-arsenopyrite mass ratio and particles size of pyrite on the leaching rate and oxidation state of arsenic. The results show that the leaching rate of arsenic increases with increasing the mass fraction of pyrite and decreases with increasing the particle size of pyrite. When the mass ratio of pyrite to arsenopyrite is 10:2 and the particles size of pyrite is less than 74 μm, the highest leaching rate of arsenic is 97.7%, which is about 43.18 % higher than that of the arsenopyrite bioleaching without pyrite. The pyrite can accelerate the transform of As(Ⅲ) to As(Ⅴ), which reduces the toxicity of pulp and makes the bioleaching system have higher bacterial density, lower pH, higher oxidation-reduction potential, and generates galvanic effect with arsenopyrite. Therefore, the bioleaching efficiency of arsenopyrite can be promoted by adding pyrite.
Key words: pyrite; arsenopyrite; Acidithiobacillus ferrooxidans; bioleaching; galvanic effect
