葡萄糖还原浸出低品位钴土矿工艺及动力学研究

Reductive Leaching and Leaching Kinetics of Cobalt from Low-Grade Asbolite Using Glucose

采用葡萄糖为还原剂，在硫酸体系中进行低品位钴土矿进行直接浸出，研究浸出过程的工艺条件和动力学。实验结果表明：在硫酸初始浓度1.6mol/L，葡萄糖初始浓度5g/L，反应温度95℃，浸出时间6h，液固比3∶1的条件下，钴土矿中Co和Mn的浸出率可同时达到99%以上。动力学研究表明：钴的浸出过程在75~95℃内符合未反应核缩减模型，浸出过程主要受内扩散步骤控制，浸出表观活化能为21.03kJ/mol。

Cobalt leaching from a low-grade asbolite was investigated using glucose as reducing agent in sulfuric acid system. The optimal conditions and the kinetics from low-grade asbolite by reductive leaching were discussed. The results show that the leaching rate of Co and Mn both reaches about 99%, while the optimum technological conditions of leaching were as follow, concentration of sulfuric acid was 1.6 mol/L, concentration of methylene blue was 5 g/L, leaching temperature was 95℃, leaching time was 4h, liquid-solid ratio was 3∶1. The kinetics studies indicate that the leaching process follows the shrinking-core model in the temperature ranging from 75-95℃, the leaching rate of Co is controlled by the internal diffusion during the leaching process, and the apparent activation energy is 21.03 kJ/mol.