摘要:This article discusses the possibility of using cheap raw materials for the treatment of wastewater from heavy metal ions using residual biomass and agricultural waste (sunflower husk, millet, buckwheat). Residual biomass is formed after the extraction of valuable components from microalgae and duckweed. The authors proposed to modify the sorption material using heat treatment and the introduction of additives, such as chitosan and thermally expanded graphite. Chitosan allows you to get sorption materials in the form of granules, which are convenient to use. The physicochemical properties of sorbents were studied. The sorption capacity for the obtained materials was from 5.0 to 32.0 mg/g.