Adsorption of Anionic Polyacrylamide on the Surface of Ion Exchange Membranes
阴离子型聚丙烯酰胺在离子交换膜上的吸附规律

Regular pattern and impact factors of adsorption of partly hydrolysis of anionic polyacrylamide (HPAM) on the surface of ion exchange membrane were studied. Static adsorption experiments were carried out to measure the adsorption capacity and time to absorption equilibrium when HPAM was adsorbed on the surface of ion exchange membrane under different temperatures and HPAM concentrations. Effects of the initial HPAM concentrations, pH value, and ion concentrations in the HPAM solution, on the adsorption were also studied. The objectives of this study were to illuminate the adsorption kinetics of HPAM on the ion exchange membrane and to investigate the influences of some impact factors on the adsorption. Results showed that anion exchange membranes had a strong affinity adsorption for HPAM, but the adsorption capacity of cation exchange membranes was almost none. The adsorption equilibrium time of HPAM onto anion exchange membranes was increased with the increasing of initial concentration of HPAM. The adsorption kinetics could be described by the pseudo-second-order kinetics model under different initial concentrations and temperatures. Under different temperatures of 303, 308 and 313 K, the process of isothermal adsorption of HPAM onto anion exchange membranes could be fitted well by Freundlich equations with a high correlation coefficient R2 (>0.99). Increasing of temperature could be able to enhance the process of adsorption. The pH value and ion concentrations of HPAM solution affected significantly on the adsorption. When pH is 6, the adsorption capacity reached the maximum value. The adsorption capacity was also increased with the increasing of ion concentrations.