Abstract
The anion-complexation mechanism and anion-adsorption capacity of a hybrid material based on hyperbranched polyethyleneimine (HBPEI) covalently bonded onto an activated carbon (AC) is presented. The anion-scavenger behavior of this hybrid material toward CrO(4)(2-), PO(4)(3-), AsO(4)(3-) and HgCl(4)(2-) was explored by direct potentiometric and adsorption measurements, which revealed a novel approach to predict the interactions between the supported polymeric complexing units and the different anions. The results were analyzed by considering the reactivity data of the HBPEI/anion (HBPEI free in solution) and AC-HBPEI/anion systems. The results corroborated that the AC-HBPEI hybrid material is an excellent anion-complexing material, whose anion adsorption ability is defined by the complexing properties of the HBPEI molecules toward the anions. This assessment provides a straightforward tool to determine the type and strength of the interactions involved in supported polymer-based/anion systems, which can provide valuable information for predicting and designing efficient energy and scavenger materials.