研究加压浸出过程中盐酸溶液提纯冶金级硅过程的动力学特征以及去除杂质Al时颗粒粒度、反应温度、总压强、盐酸初始浓度等因素对动力学的影响。结果表明:反应过程符合核收缩模型的固态产物层扩散方程;反应过程中,表观反应活化能为34.067kJ/mol,表观反应级数为0.346。硅粉粒度、温度、压强和盐酸浓度共同对Al去除率的影响的动力学数学模型经过不同条件下实验结果与计算结果进行对比验证,使用该模型计算所得结果与实验结果吻合较好。
The kinetics of pressure leaching of purification of metallurgical grade silicon with hydrochloric acid was investigated. The effects of particle size, temperature, total pressure and acid concentration on the kinetics and mechanism of aluminum removal were studied. The results show that the reaction kinetic model follows the shrinking core model and the apparent activation energy (Ea) of the leaching reaction is 4.067 kJ/mol, and the apparent reaction order of aluminum removal with pressure leaching is 0.346. The kinetic equations for the effect of particle size, temperature, total pressure and acid concentration are obtained and a mathematical model of aluminum removal rate from metallurgical grade Si (MG-Si) is developed. The equation estimates the aluminum removal with very good agreement between experimental and calculated values.