超细粉煤灰对模拟废水中孔雀石绿的吸附性能

摘要

The ultrafine fly ash (UFA) prepared by ball-milling was used as adsorption material, and its adsorption capability to malachite green (MG) in the simulated wastewater was studied by shaking adsorption method. The experimental results show that; Under the conditions of UFA dosage 10 g/Lt adsorption temperature 298 K, initial MG mass concentration 500 mg/L, shaking time 120 min and natural pH of wastewater, the equilibrium adsorption capacity can reach 49.97 mg/g and almost all MG is adsorbed on UFA; The adsorption process of MG on UFA fits well with the second-order adsorption kinetic equation with 3.95 kJ/mol of Ea; The adsorption rate is fast and controlled by intra-particle diffusion of MG in UFA; The adsorption process accords with Langmuir isotherm equation, and the saturated adsorption capacity decreases with the increasing of adsorption temperature and can reach 526.32 mg/g at 298 K; The adsorption process is a spontaneous and exothermic reaction process.%以球磨制得的超细粉煤灰为吸附材料,采用振荡吸附法研究了其对模拟废水中孔雀石绿的吸附性能.实验结果表明:在超细粉煤灰加入量为10g/L、吸附温度为298K、初始孔雀石绿质量浓度为500mg/L、振荡时间为120min、孔雀石绿废水自然酸碱度条件下,达到吸附平衡时的吸附量为49.97 mg/g,孔雀石绿几乎全部被超细粉煤灰所吸附;该吸附反应很好地符合二级吸附动力学方程,Ea为3.95kJ/mol,吸附反应速率较快,吸附过程由孔雀石绿在超细粉煤灰颗粒内部的扩散控制;该吸附符合Langmuir吸附等温方程,随吸附温度升高,饱和吸附量下降,298K下的饱和吸附量可达526.32mg/g,是自发进行的放热反应过程.