塿土表面铜吸附解吸的动力学特征及滞后效应

Hysteresis and kinetic characteristics of Copper sorption and desorption on old manured loessal soil

采用间歇法发现土娄土及不同处理土样对铜离子的吸附过程遵循二级反应动力学方程 ,吸附速率常数ka 呈 :土娄土 >去OM土娄土 >去Ca土娄土 >去Ca、OM土娄土 ;解吸过程符合两点位一级动力学方程 ,第一点位解吸速率常数kd1大于第二点位解吸速率常数kd2 ;各土样解吸速率常数的大小顺序与ka相反 ;吸附 解吸之间的滞后效应用ka/kd来衡量 。

The process of copper adsorption on old manured loessal soils treated differently followed second order reaction kinetic equations. The adsorption rate constants k a were ranked as follows: old manured loessal soil>old manured loessal soil without OM>old manured loessal soil without Ca>old manured loessal soil without both OM and Ca. The process of Cu desorption could be described by using two site first order kinetic equations, and the desorption rate constants k d of the first site was greater than those of the second. However, the changing trend of k d was in the opposition with that of k a. The k a./k d ratio reflected the hysteresis effect of Cu adsorption desorption.