材料期刊网

为了探明磷灰石在微生物浸出黄铜矿体系中的溶出特性及其对黄铜矿浸出的影响，选择粒径小于43μm的磷灰石与粒径小于74μm的黄铜矿以及At.f菌组成矿浆浸出体系，考察不同At.f菌接种量对于磷灰石溶出速率的影响及对黄铜矿浸出效果的影响。结果表明：浸出体系中含低浓度PO 43?可以提高铜的浸出效率；当At.f菌接种量为5%时，微生物浸出体系中磷灰石溶出的PO 43?浓度最小，为0.62 mg/L，此时黄铜矿的最终浸出率最高，达到57.4%，比PO 43?溶液浓度最高时体系的铜浸出率提高近30%。通过对微生物浸出前、后的浸渣进行扫描电镜、能谱分析和XRD分析发现，浸出后磷灰石表面浸蚀不明显，而黄铜矿表面浸蚀明显，同时浸渣中有新物质铵黄铁矾生成；磷灰石对于新生成的沉淀有一定的吸附作用，而且溶出较低浓度的PO 43?体系能提高黄铜矿的浸出。

To make sure the dissolution characteristics of apatite in the chalcopyrite bioleaching system and the influence on the chalcopyrite leaching efficiency, the apatite with particle size of less than 43 μm, chalcopyrite with 74 μm and Acidithiobacillus ferrooxidans (At.f) were used to prepare a bioleaching system. And the influence of different At.f inoculation amount on the apatite dissolution rate and chalcopyrite leaching effect were studied. The results show that chalcopyrite leaching efficiency can be improved when there exists PO 4 3? with low concentration in the bioleaching system. And PO43? reaches the lowest concentration of 0.62 mg/L in the bioleaching system when the At.f inoculation amount is 5%, and the final chalcopyrite leaching rate reaches the highest of 57.4%, which is 30%higher than that in the bioleaching system with the highest concentration of PO43?. Scanning electron microscope (SEM), energy dispersive spectroscope and X-ray diffraction (XRD) analyses before and after the bioleaching show that, there is not any obvious erosion on the apatite surface after leaching, while obvious erosion exists on the chalcopyrite surface and new compound ammoniojarosite generates in the leaching residue. And the precipitates newly generated can be absorbed by apatite, low concentration PO 4 3?in the bioleaching system can improve the leaching of chalcopyrite.