铁离子对土状铜矿中铜浸出影响研究

考察Fe3+浓度、Fe3+/Fe2+对土状铜矿中铜浸出率的影响,分析了酸浸过程中铁离子提高铜浸出率的机理。结果表明,在矿浆浓度30%、酸浓度36.8g/L、12.0g/L硫酸铁溶液浸出土状矿48h后,铜浸出率为62.4%,与无铁时铜浸出率相比提高了10个百分点。其中有92.6%游离氧化铜、70.3%结合氧化铜、35.6%次生硫化铜和11.8%原生硫化铜被浸出,除原生硫化铜外,均比无铁时有明显提高。并且随着Fe2+/Fe3+的降低,铜浸出率逐渐增加。增加Fe3+浓度提高了溶液电位,从而提高铜浸出率。

Effect of Iron Ions on Copper Leaching from Earthy Copper Ores

The effects of Fe3 and Fe3 /Fe2 ratio on copper leaching rate from earthy copper ores were investigated. The leaching mechanism of iron ions to improve copper leaching during acid leaching process was analyzed. The results indicate that copper leaching rate is 62.4%, which is improved by almost ten percent point compared with that of non-iron ions under the conditions including mineral concentration of 30.0%, acidity of 36.8 g/L, Fe2(SO4)3 concentration of 12.0 g/L, and leaching time of 48 h. The leaching rate of free copper oxide, combined copper oxide, secondary copper sulfide and native copper sulfide are 92.6%, 70.3%, 35.6% and 11.8%, respectively, which are significantly improved except native copper sulfide. Copper leaching rate rises with drops of Fe3 /Fe2 ratio. The potential of solution and copper leaching rate are improved by increasing Fe3 concentration.