采用高浓度碱浸对氰化尾渣进行预脱硅处理，考察搅拌速度、固液比、NaOH浓度及温度对硅浸出速率的影响，研究脱硅过程的反应动力学，得到相应的动力学方程。结果表明：当搅拌速度为400 r/min、固液比为1：5、NaOH浓度为80%、反应温度为280℃时，二氧化硅的浸出率为91.8%；碱浸过程受产物层内扩散控制，表观反应活化能为37.375 kJ/mol。通过正交实验对氰化浸金的条件进行了优化，在SiO2浸出率为91.8%，NaCN浓度为1.5 g/L，固液比为1：3，浸出时间为48 h的条件下，金的浸出率为87.83%。%High-concentration alkaline leaching was used to treat cyanide residue for predesilication. The effects of stirring speed, solid-liquid ratio, initial NaOH concentration and reaction temperature on the leaching rate of silicon dioxide were studied. The kinetics of the desilication process was studied and the corresponding kinetics equation was established. The results show that the leaching rate of SiO2 reaches 91.8% under the condition of alkaline leaching reaction temperature of 280℃, reaction time of 5 h, NaOH concentration of 80%, the solid-liquid ratio of 1:5. The alkaline leaching process is controlled by the internal diffusion on the solid product layer and the apparent activation energy is 37.375 kJ/mol. The cyanide leaching conditions of gold were optimized by the orthogonal experiment. The leaching efficiency of gold is 87.83% under the condition of the leaching rate of SiO2 of 91.8%, NaCn concentration of 1.5 g/L, the solid-liquid ratio of 1:3, leaching time of 48 h.
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