云南汤丹某氧化铜尾矿的浸出研究

摘要

The leaching behaviors of the tailings of refractory copper oxide ore from Tangdan in Yunnan Province in various solutions were studied. The conditions of conventional leaching of tailings in ammonia-ammonium solutions were investigated. The effects of dosage of oxidant, time, total ammonia concentration, concentration ratio of NR4+ to NH3, temperature, solid liquid ratio, oxidant feeding method and oxidation time on copper extraction were also studied ,the optimum condition was gotten. H2O2 was adopted as oxidant and the concentration was 11.2 mmol/L. The results show that in NH3H2O- (NH4)2CO3 system, the optimum leaching conditions are as follows: the temperature is 40 ℃, liquid solid ratio is 10/1, add H2O2 content is 0.30 mL/g, then adding to (NH4)2CO3 and NH3H2O after 2 h, c(NH4+)=3.2 mol/L, c(NH3)=0.8 mol/L, reacting another 4 h, the copper extraction is 69.3%. In NH3H2O-NH4 Cl system, the temperature is 50 ℃, liquid solid ratio is 10/1, add H2O2 content is 0.20 mL/g, then adding to NH4CI and NH3H2O after 2 h, c(NH4+)=2.25 mol/L, c(NH3)=0.75 mol/L, reacting another 6 h, the copper extraction is 70.6%.%以云南汤丹某高碱性低品位氧化铜浸出尾矿为研究对象,采用NH3·H2O-(NH4)2CO3和NH3·H2O-NH4Cl缓冲液添加氧化剂浸出,考察浸出时间、反应温度、液固比、总氨浓度及c(NH4+)/cNH3)、氧化剂用量、氧化剂添加顺序、氧化时间等因素对铜浸出率的影响,得到该尾矿的最佳浸出条件.研究结果表明:添加H2O2(11.2 mmol/L)能充分氧化次生硫化铜矿,而对原生硫化铜矿的作用有限；在NH3·H2O-(NH4)2CO3中,当液固比为10∶1,温度为40℃,加入H2O2的用量为0.3 mL/g,反应2h,然后,添加NH3·H2O及(NH4)2CO3,c(NH4+)=3.2 mol/L,c(NH3)=0.8mol/L,继续反应4h,铜浸出率达69.3％；在NH3·H2O-NH4Cl中,当液固比为10∶1,温度为50℃,加入H2O2的用量为0.20 mL/g,反应2h,然后,添加NH3·H2O及NH4Cl,c(NH4+)=2.25 mol/L,c(NH3)=0.75 mol/L,继续反应6h,铜的浸出率达70.6％.