(1. 中南大學(xué) 化學(xué)化工學(xué)院，長沙 410083；
2. 中南大學(xué) 資源加工與生物工程學(xué)院，長沙 410083；
3. 中南大學(xué) 有色資源化學(xué)教育部重點(diǎn)實(shí)驗(yàn)室，長沙 410083)
摘 要: 針對(duì)德興銅礦高銅鉬精礦特性，研究開發(fā)一種選擇性電氧化浸出新工藝。結(jié)果表明，輝鉬礦的電氧化浸出受電解液pH值的影響顯著。采用Na2CO3-NH4HCO3緩沖溶液控制電解過程pH為9左右，可以實(shí)現(xiàn)輝鉬礦的選擇性電氧化高效浸出，鉬、錸的浸出率分別為99.35%和99.79%，與非緩沖體系的電氧化過程相比，鉬、錸的浸出率分別提高了23.86%和26.50%。在選擇性電氧化過程中，黃銅礦基本上不能浸出而留在浸出渣中，電解渣中銅品位達(dá)到10.84%，回收率達(dá)到97.93%，可作為銅冶煉原料而回收。采用N235為萃取劑，對(duì)電氧化浸出液中的鉬、錸進(jìn)行溶劑萃取，將溶液中HCl濃度調(diào)整為25.48 g/L時(shí)，可實(shí)現(xiàn)鉬、錸的同時(shí)萃取，其萃取率分別為99.84%和95.19%；用17%的氨水反萃負(fù)載有機(jī)相，有機(jī)相中鉬、錸的反萃率分別為99.89%和99.54%。將反萃液pH調(diào)整為8，30℃下用D201樹脂吸附1 h，鉬、錸的吸附率分別為3.46%和92.18%，分離因子為169.56。
關(guān)鍵字: 輝鉬礦；電氧化；萃取；吸附
（1. School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;
2. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China;
3. Key Laboratory of Resources Chemistry of Nonferrous Metals, Central South University, Changsha 410083, China）
Abstract:A novel technique of selective electric-oxidation leaching, solvent extraction and ion exchange adsorption was studied for the recovery of Dexing molybdenite concentrates. The results show that the electric-oxidation leaching of molybdenite is impacted evidently by pH value of electrolyte. When the pH of electric-oxidation process was adjusted by buffered solutions of sodium carbonate and ammonium acid carbonate to about 9, MoS2 and ReS2 could be selectively oxidized, the dissolution rates of molybdenite and rhenium are 99.35% and 99.79%, respectively. Compared with that of the unbuffered system, the dissolution rates of molybdenite and rhenium increase by 23.86% and 26.50%, respectively. In the process of selective electric-oxidation leaching, chalcopyrite would not be leached, the grade of copper in the residue is 10.84% with a recovery rate of 97.93%, and it can be used as copper smelting materials. The separation of molybdenum and rhenium in the electrolyte was studied by solvent extraction and D201 resin adsorption. Coextraction of molybdenum and rhenium is found when N235 was used as an extractant and the concentration of HCl was adjusted to 25.48 g/L, the extraction efficiencies of Mo(Ⅵ) and Re(Ⅶ) are 99.84% and 95.19%, respectively. The stripping of molybdenum and rhenium to aqueous phase was investigated using 17% ammonia liquor, the stripping efficiencies of Mo(Ⅵ) and Re(Ⅶ) are about 99.89% and 99.54%, respectively. After stripping, rhenium was separated from molybdenum using D201 resin under pH 8 at 30 ℃, the adsorption rates of rhenium and molybdenum are 92.18%, 3.46%, respectively, and the separating factor is 169.56.
Key words: molybdenite; electric-oxidation; extraction; adsorption
