固定化细菌对Pb2+和Cd2+吸附的热力学和动力学研究

将天然水体中吸附Pb2+和Cd2+的优势菌种固定化后进行吸附规律 研究. 结果发现， 固定化细菌对重金属吸附的动力学过程包括快速阶段和慢速阶段， 其中 慢 速阶段符合二级吸附速率方程. Elovich模型和双常数速率模型不能描述固定化细菌对Pb 2+吸附的动 力学过程， 但能很好描述固定化细菌对Cd2+吸附的动力学过程. 固定化细菌对重金 属吸附热力学过程均可以用Henry模型描述， 且其对Pb2+的亲和力比对Cd2+的 亲和力强.

Thermodynamics and Kinetics of Pb2+ and Cd2+Adsorption onto Immobilized Dominant Bacteria

The adsorption rule of Pb~(2+) and Cd~(2+) onto immobilized dominating bacteria in natural water was studied.The results show that the adsorption dynamic process of the heavy metals onto immobilized bacteria includes a fast stage and a slow stage;the latter conforms to second-level adsorption rate equation.The(Elovich) model and the rate model with two constants cannot describe the dynamics process of the Pb~(2+)(adsorption) onto immobilized bacteria,but can describe the Cd~(2+) adsorption very well.The Henry model can describe the thermodynamics process of heavy metal adsorption,and the affinity for Pb~(2+) is stronger than for Cd~(2+).