复合吸附剂吸附废水中的重金属离子的动力学研究

采用枯草芽孢杆菌活菌体、石英砂和由二者组成的复合吸附剂对废水中的Cu2+、Zn2+和Cd2+离子分别进行了吸附动力学测试,并采用以R itch ie速率方程为基础的3种吸附动力学方程对吸附动力学数据进行校验。吸附动力学数据均能基本吻合单层吸附模型、改进双层吸附模型和R itch ie双层吸附模型,其中后两者与实验数据吻合更好;双层吸附模型能更好地描述活菌体对3种重金属离子的吸附过程;对3种吸附剂吸附3种重金属离子的动力学过程进行了比较,结果显示复合吸附剂与活菌体吸附剂对3种离子的吸附过程一致,都是快速过程。

Kinetic Study on the Composite Adsorbent Absorbing the Heavy Metal Ions in Wastewater

An absorbing kinetic testing was made for Cu~(2+),Zn~(2+),and Cd~(2+) in wastewater by using Bacillus subtilis live vaccine,silica sand,and a composite adsorbent of the two kinds of materials mentioned above,and the absorbing kinetic data was checked using three kinds of absorbing kinetic equations based on Ritchie rate equation.The absorbing kinetic data was in basic agreements with single-layer adsorption model,improved double-layer adsorption model,and Ritchie double-layer adsorption model.The improved and Ritchie double-layer adsorption models were in a better agreement with experimental data,the double layer adsorption model could better describe the process of live vaccine adsorbing the three kinds of heavy metal ions,the kinetic processes of three kinds of adsorbents absorbing three kinds of ions were compared.The results show that the composite absorbent was the same as the live vaccine absorbent in adsorbing the three kinds of ions,both of them were quick adsorption.