Methods for producing sorbents from miscanthus and study of their sorption properties for ions Pb(II) and Cd(II)

Abstract

Goal. To develop a method for the combined modification of the leaves and stems of miscanthus with the obtaining of new effective sorption materials for environmental purposes. Methods. General and special. Results. At use of miscanthus for obtaining sorbents, the plants are chemically modified, since the raw form has weak sorption properties. The resulting modified product can be got after processing plants with an alkaline solution (mercerizing), subsequent thermochemical modification in microwave followed by extrusion. Such processing preserves the integrity of the structural-frame lignocellulosic matrix and significantly improves plants’ ion-exchange, structural-porous, and sorption properties. Properties of the obtained sorbents indicate their ability to ion-exchange and complex-creation sorztion of multiply charged cations, in particular ions of heavy metal Pb2+ and Cd2+. Conclusions. The proposed methods of processing raw materials of miscanthus can be of practical use in agricultural production, and the resulting modified samples with sorption properties are promising materials in technologies of molecular and ion-exchange sorption. The obtained sorbents have a high sorption capacity concerning ions of heavy metals, particularly Pb2+ and Cd2+, and their structure-sorption characteristics are not inferior to the classical sorption materials based on carbon, silicon dioxide, aluminosilicates, etc. Therefore they can be used as efficient sorption materials for environmental clean-up of lands, contaminated with ions of heavy metal, wastewater, and soil.