State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
J Hazard Mater. 2011 May 15;189(1-2):495-501. doi: 10.1016/j.jhazmat.2011.02.063. Epub 2011 Feb 26.
To determine the isotherm parameters and kinetic parameters of adsorption of anion polyacrylamide (APAM) from aqueous solution on PVDF ultrafiltration membrane (PM) and modified PVDF ultrafiltration membrane (MPM) is important in understanding the adsorption mechanism of ultrafiltration processes. Effect of variables including adsorption time, initial solution concentration, and temperature were investigated. The Redlich-Peterson equation of the five different isotherm models we chose was the most fitted model, and the R(2) was 0.9487, 0.9765 for PM and MPM, respectively; while, the pseudo-first-order model was the best choice among all the four kinetic models to describe the adsorption behavior of APAM onto membranes, suggesting that the adsorption mechanism was a chemical and physical combined adsorption on heterogeneous surface. The thermodynamic parameters were also calculated from the temperature dependence (Δ(r)G(m)(θ), Δ(r)H(m)(θ), Δ(r)S(m)(θ)), which showed that the process of adsorption is not spontaneous but endothermic process and high temperature favors the adsorption.
确定阴离子型聚丙烯酰胺（APAM）从水溶液中在聚偏氟乙烯超滤膜（PM）和改性聚偏氟乙烯超滤膜（MPM）上的吸附等温线参数和动力学参数对于理解超滤过程的吸附机制非常重要。考察了吸附时间、初始溶液浓度和温度等变量的影响。我们选择的五个不同等温线模型中的 Redlich-Peterson 方程最适合，R(2)分别为 0.9487 和 0.9765；而对于所有四个动力学模型，伪一阶模型是描述 APAM 吸附到膜上的吸附行为的最佳选择，表明吸附机制是在非均相表面上的化学和物理联合吸附。从温度依赖性（Δ(r)G(m)(θ)、Δ(r)H(m)(θ)、Δ(r)S(m)(θ)）计算了热力学参数，表明吸附过程不是自发的而是吸热过程，高温有利于吸附。
