Efficient pollutants removal by amino-modified nanocellulose impregnated with iron oxide

Abstract

A novel adsorbent, NC-PEG, obtained by modification of nanocel­lulose (NC) with PEG-6-arm amino polyethylene glycol (PEG-NH₂) via maleic anhydride (MA) linker, was used for removal of Cd²⁺ and Ni²⁺ from water. A subsequent precipitation of iron oxide (FO) from goethite on NC-PEG was employed to pro­duce NC-PEG/FO adsorbent which was used for As(V) and As(III) removal. In a batch test, the influence of pH, contact time, initial ion concentration and temperature on the adsorption efficiency were studied. The maximum adsorp­tion capacities found for Cd²⁺ and Ni²⁺, obtained by the use of Langmuir model, were 37.9 and 32.4 mg g^-1 at 25 °C, respectively. Also, high As(V) and As(III) removal capacities of 26.0 and 23.6 mg g^-1 were obtained. The thermo­dynamic parameters indicated endothermic, feasible and spon­ta­neous nature of the adsorption process. The kinetic study, i.e., fitting by Weber–Morris model predicted that intra-particle diffusion was the rate-controlling step. The ability for multi-cycle reusability of both NC-PEG and NC-PEG/FO, represents a posi­tive indicator when considering their possible applic­ations.