Peculiarities of Sorption of Heavy-Metal Ions by Polysaccharide and Polyamide Biopolymers

The results of a study of sorption properties of native and modified materials of polysaccharide and polyamide nature are presented, and the physicochemical regularities of the distribution of d-metals in a "biopolymer-aqueous solution" heterophase system have been established. The experimental sorption isotherms were analyzed within the framework of the Langmuir, Freundlich, and Dubinin-Radushkevich models. The sorption kinetics is most correctly described by the pseudo-second-order model. The influence of various factors affecting sorption efficiency such as temperature, mixing rate and others was examined. The effect of the environment pH on the sorption of heavy-metal ions onto polysaccharide and polyamide sorbents was observed. A number of regularities of the competitive sorption process of ?(2+)/?(+) cations within the acid pH region with the involvement of various functional groups was established. The prospects are determined for the use of polysaccharide and polyamide biosorbents modified by employing new techniques that include a directional modification of surface properties based on the "structure-sorption activity" relationship.