两性-非离子表面修饰剂复配修饰土娄土吸附Cd^(2+)的动力学

Adsorption kinetics of Cd^(2+) on amphoteric-nonionic surface active agent co-modified Lou soil

【目的】研究两性表面修饰剂和非离子表面修饰剂复配修饰土娄土对重金属Cd2+的吸附动力学特征,为两性-非离子表面修饰剂复配修饰土娄土对重金属Cd2+的吸附特征和机制的研究提供理论依据。【方法】以原土,即未修饰土娄土(CK)为对照,以十二烷基二甲基甜菜碱(BS)作为两性表面修饰剂,辛烷基酚聚氧乙烯醚(OP)作为非离子表面修饰剂,采用批处理方法,研究20,40℃时,BS单一修饰和不同比例BS与OP复配修饰土娄土对Cd2+的吸附动力学。【结果】在20和40℃,BS-OP复配修饰土娄土吸附Cd2+的快速吸附阶段平均速度(Vf)分别表现为100%BS>50%BS≈50%BS+50%OP>100%BS+100%OP≈100%BS+50%OP>CK>50%BS+100%OP;100%BS>100%BS+50%OP>100%BS+100%OP>50%BS>50%BS+50%OP≈50%BS+100%OP>CK。BS修饰比例相同时,修饰土娄土的Vf总体上随着OP修饰比例增大而下降;OP修饰比例相同时,随着BS修饰比例的增加,修饰土娄土的Vf均增大。【结论】在两性-非离子表面修饰剂复配修饰土娄土对Cd2+的吸附过程中,BS起促进作用,OP起抑制作用,描述修饰土娄土吸附Cd2+的较佳模型是双常数动力学模型。

【Objective】 Investigation on the characteristic of adsorption kinetics of Cd2+ on amphoteric-nonionic surface active agent co-modified Lou soil could provide a theoretical foundation for the characteristic and mechanism of adsorption kinetics of Cd2+ on amphoteric-nonionic surface active agent co-modified Lou soil.【Method】 The original soil,unmodified soil(CK),was used as the control,Dodecane-Betaine(BS) as amphoteric surface active agent and Octylphenol polyoxyethylene ether(OP) as nonionic surface active ...