Kinetics of Enhanced Adsorption by Polarization for Organic Pollutants on Activated Carbon Fiber
电增强活性炭纤维吸附有机污染物的动力学研究

The adsorption kinetics for model pollutants on the activated carbon fiber(ACF) by polarization was investigated.Kinetics data obtained for the adsorption of these model pollutants at open-circuit and 400mV,-400mV polarization was applied to the Lagergren equation,and adsorption rate constants(Ka) were determined.With the anodic polarization of 400mV,the capacity of sodium phenoxide increases from(0.008 3mmol·g-1) at open-circuit to 0.18mmol·g-1,and a seventeen-fold enhancement is achievable;however,the capacity of pnitrophenol decreases from 2.93 mmol·g-1 at open-circuit to 2.65 mmol·g-1.With the cathodal polarization of-400mV,the capacity of aniline improves from 3.60 mmol·g-1 at open-circuit to 3.88 mmol·g-1;however,the capacity of sodium dodecylbenzene sulfonate reduces from 2.20 mmol·g-1 at open-circuit to 1.59 mmol·g-1. The enhancement for electrosorption changes with different groups substituting. Anodic polarization enhances the adsorption of benzene with electron-donating group.But whether anodic or not cathodal polarization has less effect on the adsorption of electron-accepting aromatic compounds,and decreases the adsorption of benzene bearing donor-conjugate bridge-acceptor but increases the adsorption rate.Electrostatic interaction plays a very important role in electrosorption of ion-pollutants.