高碱复杂氧化铜矿石酸浸动力学研究

Dynamic study on acid leaching of complex alkaline copper oxide ore

为了研究某高山矿区高碱复杂氧化铜矿石硫酸浸出过程动力学,试验采用电子显微镜扫描、电子探针分析研究了矿石的化学特征;对浸出温度、矿石粒度、液固比和初始酸度等因素进行了多水平的搅拌浸出试验。结果表明,选取的各因素能显著影响矿石的浸出率和浸出速率。采用未反应的缩小核模型进行浸出动力学分析,从动力学模型、表观活化能和颗粒表层产物3方面确定表面化学反应为浸出过程的控制步骤,得出矿石表观活化能和宏观浸出速率方程,并解释了反应后期浸出体系的化学动态平衡。

To study the dynamics of sulphuric acid leaching process of complex alkaline copper oxide ore in an alpine mine,electronic scanning and electron probe was adopted to study the chemical characteristics.Temperature,particle size,liquid-solid ratio and initial acid concentration were selected as influencing factors in agitation leaching. Results show the four factors can significantly affect the leaching rate and copper recovery.On the basis of shrinking core model,analysis on dynamic model,apparent activation energy and particle surface layer product indicates that the surface chemical reaction is the rate limiting step.Apparent activation energy,macroscopic leaching rate equation and chemical kinetic equilibrium of leaching system in anaphase is also presented.