Pb~(2+) 在天然膨润土上的吸附动力学研究.pdf

11 1 2010年第4期 水科学与工程技术 ·37· P，， 4— 4—i — ^ 0 ．呻 {． 土工试验 ’ 1 ／ Pb2+在天然膨润土上的吸附动力学研究 李 昕，何少华，邝应林，司建伟，张 宇 (南华大学 城市建设学院，湖南衡阳421001) 摘 要：采用静态法探讨了天然膨润土吸附废水中Pb“的主要影响因素及动力学。研究表明，在实验条件下，当天然膨润土用量增加 时，吸附量随之减少。而当初始pH值在4～6变化时，吸附量随着pH值的增大而增加。此外，当温度或Pb 初始浓度升高时．吸附量也随 之增大。由于反应速度较快，吸附60rain后基本达到平衡，吸附90rain后天然膨润土对Pb“的吸附量为6．52～19．15mg／g。吸附动力学规 律遵从Lagergren准二级反应模型。 关键词：天然膨润土；铅；吸附；动力学 中图分类号：TU43 文献标识码：A 文章编号：1672—9900(2010)04—0037—03 Study on the adsorption kinetics characteristics of Pb on natural bentonite LI Xin，HE Shao—hua，KUANG Ying—lin，SI Jian—wei，ZHANG Yu (School of urban construction,University ofSouth China,Hengyang 421001，China) Abstract：Through batch experiments，we i nvestigated the use of natural bentonite in treating the adsorption of Pb in aqueous solutions，including the mainly affecting factors and the kinetics．Under the experiment conditions，the adsorption capacity was decreased with the increasing amounts of natural bentonite．When pH was between 4 and 6，the adsorption capacity was increased with the increasing pH．Moreover，the adsorption capacity increased with the increasing temperature and the Pb initial concentration．Because of the rapid adsorption speed．the adsorption process approximately reached e— quilibrium in 60min and the adsorption capacity of Pb was 6．52~19．15mg／g after 90min．The adsorption kinetics fitted well to the pseudo-second order reaction models． Key words：natural bentonite；Pb“；adsorption；kinetics 膨润土是以蒙脱石为主要矿物成分的非金属矿产．蒙脱 膨润土具有较大的比表面积和良好的吸附性能，在重金 石结构是由两个硅氧四面体夹一层铝氧八面体组成的2：1型 属废水中具有重要的应用前景 。本文探讨了天然膨润土吸 晶体结构 。