过硫酸钠氧化浸出石煤中的钒及其动力学研究

Study on Oxidation Leaching of Vanadium from Stone Coal with Sodium Persulfate and its Kinetics

为了探讨石煤氧化浸出机理,在常压下采用硫酸溶液直接浸出石煤钒矿,通过在酸浸过程中加入氧化剂过硫酸钠,考察了各工艺条件对V浸出率的影响。结果表明:在过硫酸钠用量2%、硫酸用量35%、固液比1∶1、浸出温度95℃、浸出时间11 h的实验条件下,V浸出率达到88.9%。对不同反应温度下V浸出率-时间曲线进行拟合,拟合结果表明该氧化浸出过程符合收缩未反应芯模型,浸出过程受颗粒表面化学反应控制。根据Arrhenius公式,使用曲线拟合法,近似求得该反应表观活化能为66.08 kJ·mol^(-1)。

In order to explore the mechanism of oxidation leaching of stone coal,the vanadium was leached directly from stone coal vanadium ore by sulfuric acid solution at atmospheric pressure.By adding sodium persulfate in the process of acid leaching,the effects of various conditions on vanadium leaching rate were investigated.The results show that V leaching rate reached 88.9% under the experimental conditions of sodium persulfate 2% ,sulfuric acid 35 %,solid-liquid ratio 1:1,leaching temperature 95℃ and leaching time 11 h.Fitting the V leaching rate-time curves at different reaction temperatures shows that the oxidation leaching process conforms to the shrinking core model and the leaching process is controlled by the chemical reaction on the particle surface.According to Arrhenius equation,the apparent activation energy of the reaction was approximately calculated to be 66.08 kJ ·mol^-1 by using curve fitting method.