蒙脱石对四环素类抗生素的吸附平衡及动力学  

Adsorption Equilibrium and Kinetics of Adsorbing Tetracycline Antibiotics on Montmorillonite

作　　者：邹星[1] 吴小莲[1] 莫测辉[1] 李彦文[1] 高鹏[1] 黄显东[1] 刘利伟[1] 

机构地区：[1]暨南大学环境工程系广东省普通高校水土环境毒害性污染物防治与生物修复重点实验室,广东广州510632

出　　处：《高校化学工程学报》2011年第3期524-528,共5页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金项目(30671208;40773062);中央高校基本科研业务费专项资金项目(21610410;21609709);广东省自然科学基金重点项目(07117909);广东省科技计划项目(2005B20801002;2006B20601003;2010B020311006);广东省高校高层次人才项目;东莞市科技研究计划项目(2007108101110);惠州市科技研究计划项目(2009B010001009);广州市科技计划项目(10A82070466)

摘　　要：为吸附处理抗生素污染水体,以蒙脱石为吸附剂进行2种四环素类抗生素（四环素和土霉素）的静态吸附试验,考察平衡时间、初始浓度、pH值、阳离子种类与强度等对吸附性能的影响。结果表明,蒙脱石对四环素和土霉素的吸附可划分为初始快速吸附阶段和随后缓慢吸附阶段,符合二级动力学方程,吸附速率常数分别为0.206 g·mg-1·h-1和0.099 g·mg-1·h-1;吸附等温线均能较好地符合Freundlich方程和Langmuir方程,最大吸附量（Qm）分别为313 mg·g-1和189 mg·g-1;在强酸性条件（pH值为2~3）下吸附能力最强,其次为中性-弱碱条件;随着Ca2＋离子浓度升高,蒙脱石对四环素和土霉素的吸附作用逐渐减弱。因此,本研究获得了能同时高效吸附四环素和土霉素蒙的吸附剂,为四环素类污染水体的吸附处理提供了科学依据。Aiming at the removal of antibiotics in water,a static adsorption experiment was conducted to investigate the influences of equilibrium time,initial concentration,pH value,and cation species on adsorption of two kinds of tetracycline antibiotics（tetracycline and oxytetracycline） by montmorillonite.Results show that the adsorption process of tetracycline and oxytetracycline by montmorillonite could be divided into the initial fast adsorption stage and the slow adsorption stage,which follow pseudo-second-order kinetic equation with adsorption rate of 0.206 g·mg-1·h-1 for tetracycline and 0.099 g·mg-1·h-1 for oxytetracycline,respectively.Adsorption isotherms of tetracycline and oxytetracycline with montmorillonite can be well described by both Freundlich equation and Langmuir equation,with the maximum adsorption capacities（Qm） of 313 mg·g-1and 189 mg·g-1,respectively.The maximum adsorption capacities of tetracycline and oxytetracycline on montmorillonite could be obtained when pH value is 2~3,followed by pH value from 7 to 9.Adsorption capacity of tetracycline and oxytetracycline on montmorillonite decreases with the increase of Ca2＋ concentrations.This research provides an effective sorbent which can simultaneously adsorb tetracycline and oxytetracycline and provides the scientific basis for the adsorption and removal of tetracycline antibiotics in water by montmorillonite.

关 键 词：四环素类抗生素 蒙脱石 吸附 动力学 去除 

分 类 号：X52[环境科学与工程—环境工程] R978.14[医药卫生—药品]