锑冶炼砷碱渣水热硫化沉淀脱砷过程的动力学

Arsenic Removal Kinetics of Hydrothermal Sulfide Precipitation for Arsenic-alkali Residue from Antimony Smelting

用水热法浸取炼锑砷碱渣,以硫化钠为沉淀剂进行硫化脱砷过程动力学试验。考察在不同温度和硫化钠用量时沉淀时间与沉淀净化效果的关系,并建立动力学模型。结果表明,反应温度、硫化钠浓度对沉砷净化过程都有一定的影响,其中反应温度对净化率影响的敏感度较低;沉砷净化动力学模型符合n=0.426 1时的Avrami方程:-ln(1-x)=1057.33CA-0.4963t0.4261exp(-1.591×104/RT);表观活化能为15.91kJ/mol,反应级数为-0.496 3,脱砷过程反应较快,属扩散控制。

Arsenic-alkali residue was hydrothermally leached with sodium sulfide as precipitating agent. The kinetics of sulfide precipitation of arsenic removal was studied. The relationship between precipitation duration and purification rate were investigated under different temperature and dosage of sodium sulphide. Dynamic model was established. The results show that both reaction temperature and concentration of sodium sulfide have certain effect on arsenic purification process while the effect of reaction temperature on purification rate is less sensitive effect. Arsenic precipitation purification dynamics model fits for Avrami equation model with n=0. 4261： -ln（l-x） =1057.33Cn 0.4963 to.4Z61exp（-1. 591× 104/RT）. Its apparent activation energy is 15.91 kJ/mol and reaction order is -0. 496 3. The arsenic removal process is faster in reaction with diffusion controlled.