SDS-硅藻土吸附亚甲基蓝和孔雀石绿染料的动力学和热力学

文章主要研究了SDS-硅藻土对亚甲基蓝和孔雀石绿两种染料的吸附动力学和热力学。研究结果表明,SDS-硅藻土对亚甲基蓝和孔雀石绿的平衡吸附量分别为16.3mg/g和20.1mg/g。亚甲基蓝和孔雀石绿在SDS-硅藻土上的吸附行为均可用Langmuir等温方程来描述,20℃时的相关系数分别为0.939 1和0.963 6,升温有利于吸附的进行。准二级吸附速率方程能更好的描述亚甲基蓝和孔雀石绿在SDS-硅藻土上的吸附动力学,20℃时的相关系数分别为0.991 0和0.990 8。通过计算不同温度各热力学参数ΔG、ΔH和ΔS,理论上证实该吸附为一自发的吸热过程,且以物理吸附为主。

Kinetics and Thermodynamics of Adsorption of Methylene Blue and Malachite Green on SDS-Diatomite

The kinetics and thermodynamics of adsorption of methylene blue and malachite green on SDS-diatomite were investigated mainly.The results indicated that the adsorption capacity of methylene blue and malachite green on SDS-diatomite was 16.3mg/g and 20.1mg/g,respectively.Equilibrium data of Langmuir isotherms showed significant relationship to the adsorption of methylene blue and malachite green on SDS-diatomite,the correlation coefficient was 0.939 1 and 0.963 6 at 20℃,and the adsorption process was increased with the increasing temperature.Adsorption process of SDS-diatomite to methylene blue and malachite green accorded with pseudo-second order kinetic equations,the correlation coefficient was 0.991 0 and 0.990 8 at 20℃.At different temperatures by calculating the thermodynamic parameters ΔG,ΔH and ΔS,confirmed that the adsorption reaction was a spontaneous endothermic process theoretically,and the adsorption process was physical adsorption dominantly.