Development of an anion imprinted polymer for high and selective removal of arsenite from wastewater

摘要

A novel cyclic functional monomer (CFM) was used to develop an As(III)-ion imprinted polymer (As-IIP). CFM possesses a positively charged imidazolium moiety and its specific cyclic size matches that of As(III). Batch adsorption experiments showed that the As-IIP has a maximum As(III) adsorption capacity of 55 mg/g, while that of the control polymer (CP) is only 25 mg As(III)/g. Adsorption isotherms for As(III) agree with the Langmuir model, suggesting monolayer adsorption. Kinetic studies showed that the adsorption process followed pseudo-second-order kinetics. The relative selectivity coefficients of As-IIP compared to CP for Cl-/H2AsO3-, SO42-/H2AsO3-, HPO42-/H2AsO3-, NO3-/H2AsO3-, and Mo7O246-/H2AsO3- are 1.03, 1.95, 2.55, 1.52 and 2.51, respectively. The removal efficiency of As-IIP for As(III) in actual industrial wastewater was nearly 100%, which confirms that As-IIP has a high adsorption capacity as well as selectivity for the removal of As(III) from wastewater.