草木灰对亚甲基蓝的吸附研究

The Study of the Adsorption of Methylene Blue by Plant Ash

本实验目的是研究草木灰对吸附亚甲基蓝的去除效果,探讨了亚甲基蓝初始量、吸附时间、pH值等对吸附效果的影响,并运用伪一级、伪二级反应动力学模型和Laugmuir、Freundlich等温线模型进行拟合。结果表明,草木灰对亚甲基蓝溶液的吸附在5 min^30 min速率比较快,约在65 min内达到吸附平衡,pH越大越有利于吸附,浓度在5mg/L时草木灰对亚甲基蓝的吸附最佳。与伪二级动力学曲线模型拟合效果较好,由Laugmuir等温线模型计算得出理论最大吸附容量Qm为2.275 mg/g,吸附性能优异。

This study focused on the removal efficiency of methylene blue by the plant ash and dicussed the influences of the initial amount,adsorption time and pH value of methylene blue on the removal efficiency.Fitting process is conducted on used pseudo-first order kinetic model,pseudo-second order kinetic model,Laugmuir isotherm model and Freundlich isotherm model.The results showed that the rate of the plant ash on the absorption of methylene blue solution was fast within 5 min to 30 min and reached absorption equilibrium at 65 minutes approximately,and High pH value was conducive to adsorption and the the adsorption effect was optimum when the absorption concentration was 5mg /L.When the theoretical maximum adsorption capacity（Qm） was 2.275 mg/g calculated by Laugmuir isotherm model,the adsorption of methylene blue by plant ash had good performance.