经离子液体水溶液预处理玉米芯对亚甲基蓝吸附性能的研究

Study on Adsorption of Methylene Blue by the Corncob Pretreated by Ionic Liquid Aqueous Solution

目的:采用离子液体[Bmim]Cl水溶液对玉米芯进行预处理,探讨该吸附剂对废水中亚甲基蓝的吸附效果。方法:分别进行静态吸附动力学和热力学研究,采用准一级动力学方程、准二级动力学方程、Elovich和颗粒内扩散方程四种动力学经验方程对动力学过程进行分析;采用Freundlich、Langmuir、DR和Temkin四种吸附等温方程对热力学过程进行分析。结果:拟合结果表明,吸附过程符合准二级动力学方程,Langmuir等温吸附模型能够较好地描述玉米芯对亚甲基蓝吸附的热力学过程。此外,较高的温度有利于吸附,吸附过程为吸热过程。结论:经离子液体预处理后的玉米芯具有较好的吸附能力,吸附行为符合Langmuir吸附等温线,反应级数符合准二级反应动力学特征。

Objective：Corncob was pretreated with ionic liquid [Bmim]Cl aqueous solution.Then it was selected to adsorb methylene blue from aqueous solutions.Methods：The adsorption process was analyzed via four kinds of kinetic equations（Pseudo-first-order kinetic model,pseudo-second-order kinetic model,Elovich equation,and intra-particle diffusion equation）and four isotherm models（Freundlich,Langmuir,D-R and Temkin equations）,respectively.Results：It shows that the process could be described well by pseudo-second-order kinetic and Langmuir isotherm items.In addition,the relatively higher temperature was conducive to the adsorption,suggesting that the process was endothermic.Conclusion：The corncob pretreated with ionic liquid still exhibited a good adsorption capacity.The adsorption be-havior was consistent with the Langmuir adsorption isotherm and the pseudo-second-order reaction kinetic.