汤丹某氧化铜尾矿的浸出研究

【作者】 马建业；

【导师】 刘云清；

【作者基本信息】 中南大学 ， 物理化学， 2011， 硕士

【摘要】 随着近地表富矿的日趋枯竭,资源问题已经成为制约中国可持续发展战略的根本性问题,采用溶浸技术从低品位矿石中回收金属就显得意义重大。本文目的在于研究开发出一种有效利用氧化铜浸出尾矿的新方法,就云南汤丹某氧化铜尾矿在氨性溶液中的行为做了研究：在铵盐-氨水缓冲溶液中搅拌浸出尾矿样中的铜,得到常规浸出条件；研究氧化剂存在下的浸出行为,考察了氧化剂用量,浸出时间,浸矿剂总浓度及[NH4+]/NH3,反应温度,液固比,氧化剂添加顺序,氧化时间等因素对铜浸出率的影响,得到了该铜矿浸出的最佳条件。研究结果表明,该铜矿的浸出主要是扩散控制,浸出时间,反应温度,液固比对铜的浸出率均有显著影响。氧化剂选用H202,其物质的量浓度为0.0112mol/L。NH3·H2O-(NH4)2CO3中,反应温度40℃,液固比＝10：1,加入H2O2, c(H2O2)=0.30mL/g,反应2h；然后添加NH3·H2O及(NH4)2CO3, c(NH4+)= 3.2mol/L, c(NH3)=0.8 mol/L,继续反应4h,铜浸出率69.3%。NH3·H2O-NH4Cl中,反应温度50℃,液固比=10：1,先加入H2O2, c(H2O2)=0.20mL/g,反应2h；然后添加NH3·H2O及NH4Cl,c(NH3)=0.75mol/L,c(NH4+)=2.25 mol/L,继续反应6h,铜浸出率达70.6%。NH3·H2O-(NH4)2SO4中,反应温度50℃,液固比=10：1,先加入H2O2,c(H2O2)=0.15mL/g,反应2h；然后添加NH3·H2O及(NH4)2SO4, c(NH3)= 0.67mol/L, c(NH4+)= 1.33mol/L继续反应4h,铜浸出率59.2%。浸出渣的物相分析表明,添加H2O2后,充分氧化了次生硫化铜矿,而对原生硫化铜矿作用有限。氧化剂下的浸出与常规浸出相比较,矿样中自由氧化铜矿、结合氧化铜矿及硅孔雀石的浸出率基本不变,而次生硫化铜矿的浸出率提高了2-5倍,这是氧化剂下铜浸出率较高的根本原因。更多还原

【Abstract】 With depletion of the high content ores near-surface layer, resources has become essential issue of sustainable development strategies in China. Therefore, recovering copper from copper oxide,complex ores and low grade ores is more significance by leaching technology. The aim of this work is developing a new method to leach copper oxide ores and to utilize low-grade copper ores efficiently. In this paper, the leaching behaveiors of the tailings of refractory copper oxide ore from Tangdan in Yunnan Province in various solutions have been studied.The conditions of conventional leaching of tailings in ammonia-ammonium solutions have been investigated. The effects of dosage of oxidant, time, total ammonia concentration, [NH4]+/NH3,temperature,solid liquid ratio, oxidant feeding method and oxidation time on copper extraction have been also studied,to get the optimum condition.The results shows that the leaching process of copper ores is controlled by diffusion step.The leaching time, temperature, solid liquid ratio have significant effects on copper extraction. H2O2 is adopted as oxidant and the concentration is 0.0112mol/L.In NH3·H2O-(NH4)2CO3 system,the optimum leaching conditions are 40℃,liquid solid ratio 10/1, add H2O2(0.30mL/g),then adding to (NH4)2CO3 and NH3·H2O after 2 hours,c(NH4+)=3.2mol/L, c(NH3)=0.8 mol/L, reacting another 4 hours. The copper extraction is 69.3%. In NH3·H2O-NH4Cl system, the optimum leaching conditions are 50℃, liquid solid ratio 10/1, add H2O2(0.20mL/g), then adding to NH4C1 and NH3·H2O after 2 hours, c(NH4+)=2.25mol/L, c(NH3)=0.75mol/L, reacting another 4 hours. The copper extraction is 70.6%. In NH3·H2O-(NH4)2SO4 system the optimum leaching conditions are 50℃, liquid solid ratio 10/1, add H2O2(0.20mL/g), then adding to (NH4)2SO4 and NH3·H2O, c(NH4+)= 1.33mol/L, c(NH3)=0.67mol/L, reacting another 4 hours. The copper extraction is 59.2%.The phase analysis of residue of leaching tailing ore shows that the secondary copper sulphide ore is oxidized sufficiently by adding H2O2, but the primary copper sulphide ore almost remains unchanged.Compared with conventional leaching, while that from the secondary copper sulphide ore was raised 2～5 times, which is the basic reason of relatively high copper extraction on the effect of oxidant.更多还原