超细粉煤灰对模拟废水中孔雀石绿的吸附性能

Adsorption Capability of Ultrafine Fly Ash to Malachite Green in Simulated Wastewater

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10 g/L、吸附温度为298 K、初始孔雀石绿质量浓度为500 mg/L、振荡时间为120 min、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3.95 kJ/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,298 K下的饱和吸附量可达526.32 mg/g,是自发进行的放热反应过程。

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/L, adsorption temperature 298 K, initial MG mass concentration 500 rag/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.