摘要
基于人们长期忽略腐殖质的表面电场效应这一事实,以腐殖质胶体为研究对象,进行了Ca2+/Zn2+交换动力学实验.利用外力场体系物质扩散的普适性耦合扩散理论所建立起来的新速率方程,表明:腐殖质胶体上金属离子的吸附动力学受腐殖质胶体颗粒表面电场的强烈影响.实验表现出明显的"一级"动力学特征,并随电解质Ca(NO3)2浓度的增大,吸附速率常数k逐渐降低,平衡吸附量N∞也逐渐降低.当不考虑电场作用时,平衡吸附量N′∞的理论值是N∞的1/2490~1/90,吸附速率常数k′的理论值是k的1/2480~1/90.
Taking into consideration the fact that the effect of the surface electric field of humus has long been neglected, an experiment of Ca^2＋/Zn^2＋ dynamics was carried out with humic colloid as the material. A completely new coefficient rate equation was established using the coupling diffusion in external fields theory, which showed that the electric field of humic colloid particle surface had a significant influence on the adsorption kinetics of the metal ionsa on the humic colloid. It also showed an obvious character of first- order kinetics. With the increase in the concentration of the supporting electrolyte Ca（NO3）2, the coefficient rate of adsorption k and the equilibrium adsorption capacity N∞ decreased gradually. The theoretical value of the equilibrium adsorption capacity N＇∞ would be 1/2490-1/90 smaller than the N∞ , and the coefficient rate of adsorption k＇ would be 1/2480-1/90 smaller than the k without considering the role of surface electric field.
出处
《西南大学学报（自然科学版）》
CAS
CSCD
北大核心
2010年第3期77-81,共5页
Journal of Southwest University(Natural Science Edition)
基金
国家自然科学基金资助项目(40671090
40740420660)
关键词
腐殖质胶体
表面电场
离子交换吸附
humic colloid
surface electric field
ion exchange adsorption
