负载镧的EGDE交联壳聚糖微球对氟离子的吸附平衡与吸附动力学  

Adsorption Equilibrium and Kinetics of Fluoride on La(Ⅲ)-Loaded Chitosan Beads Crosslinked by EGDE

作　　者：李永富[1] 孟范平[1] 杜秀萍[1] 周游[1] 

机构地区：[1]中国海洋大学海洋环境科学与工程学院海洋环境与生态教育部重点实验室,山东青岛266100

出　　处：《中国海洋大学学报（自然科学版）》2012年第6期34-39,共6页Periodical of Ocean University of China

基　　金：山东省优秀中青年科学家科研奖励基金项目(BS03124)资助

摘　　要：采用负载镧的乙二醇二缩水甘油醚(EGDE)交联壳聚糖微球对含氟水进行吸附处理。该吸附剂的适宜工作条件为:温度30～50℃,pH值7.0,吸附时间30min。用吸附等温线描述了F-在吸附剂上的吸附平衡,并用动力学模型研究了其吸附动力学机制。结果表明:吸附剂对F-的吸附平衡符合Langmuir吸附等温线和Freundlich吸附等温线,饱和吸附容量为25.7mg.g-1;该吸附剂对F-的吸附既包含化学吸附又包含物理吸附过程,以单分子层的化学吸附为主;吸附动力学符合拟二级动力学方程,吸附过程受化学吸附机理的控制,颗粒内扩散和液膜形成的边界层是其限速步骤。The water containing high fluoride ions was treated by the applicability of La（l]I）-loaded chi- tosan beads crosslinked by ethylene glycol diglycidyl ether（EGDE）. The suitable treatment conditions were. temperature was 30450 ℃, pH value was 7.0, and contact time was 30min. The adsorption equi- librium behavior was described using adsorption isotherms; and several dynamic models were adopted to interpret the adsorption dynamics mechanism. The equilibrium data fitted well both to Langmuir and Fre- undlich isotherms; the maximum adsorption capacity for F- was 25. 7 mg · g^-1. It was found that the physical adsorption and the chemical adsorption coexisted; the monomolecular layer chemical adsorption was the dominant type. Adsorption kinetics study revealed that the adsorption process followed pseudo- second-order model; the adsorption process was complex and controlled by chemical adsorption mecha- nism; both the boundary of liquid film and intraparticle diffusion contributed to the rate-determining step.

关 键 词：壳聚糖 镧 乙二醇二缩水甘油醚(EGDE) 氟 吸附等温线 吸附动力学 

分 类 号：X131[环境科学与工程—环境科学]