用强碱性阴离子交换树脂回收氰化物的研究

Recovery of cyanide with strongly basic anion exchange resin

文中针对D2 - 1树脂和 2 0 1× 7树脂对氰化物的吸附和解吸性能进行了对比研究。研究主要集中在两种树脂的最佳吸附条件、饱和吸附量和吸附的热力学及动力学规律上 ,确定了两种树脂的最佳吸附条件均为 :pH值控制在 10～ 11之间 ,室温 ,静态吸附振荡 15min ;D2 - 1树脂和 2 0 1× 7树脂的静态饱和吸附量分别为 :15 .4 9mg/ml湿树脂 ,2 5 .39mg/ml湿树脂 ;吸附和解吸的速率常数 :D2 - 1树脂为 1.0 4× 10 - 2 s- 1和 1.4 8× 10 - 2 s- 1,2 0 1× 7树脂为 1.0 4× 10 - 2 s- 1和 2 .12× 10 - 2 s- 1,且吸附过程符合Freundlish经验等温式。同时 ,在研究解吸的过程中选择中性NaCl作为解吸剂 ,取得了良好的解吸效果。实验结果表明 ,2 0 1× 7树脂对氰化物的吸附性能优于D2 - 1树脂 ,在处理、回收提金废水中的氰化物方面更具有工业应用的前景。

The cyanide adsorption and cyanide desorption performances of D2-1 resin and 201×7 resin were studied contrastively. The study focused on the optimum adsorptive condition,the capacity of saturation adsorption and adsorption regularity of dynamics and thermodynamics. The optimum conditions for cyanide adsorption of both resins were determined as follows: the pH value is between 10～11,the temperature is normal and the static state lasts 15 min. The capacity of static saturation cyanide adsorption of these two resins is 15.40 mg/ml wet resin and 25.39 mg/ml wet resin respectively. The adsorption speed constant and desorption speed constant of D2-1 resin is 1.04×10 -2 s -1 and 1.48×10 -2 s -1 respectively,while that of 201×7 basic anion exchange resin are 1.01×10 -2 s -1 and 2.12×10 -2 s -1 respectively. The adsorption process of these tow resins coincides with Freundlish's equation. Moreover,NaCl was selected as a good neutral strippant.The results illustrate that the adsorptive performance of 201×7 resins is better than that of D2-1 resin. It has industrial application prospect in the field of cyanide disposal and recovery.