Effect of chitosan/biochar composites on Cr ion adsorption.

Different load prepared by impregnation method of chitosan-coconut shell biochar (C-CBC) and chitosan-apricot shell biochar (C-ABC) compound adsorption material. SEM and XPS were used to characterize the composite adsorption material, and the adsorption performance of the composite material to Cr in electroplating wastewater was studied. The results showed that chitosan and biochar were combined to form a composite with loose porous structure. The adsorption capacity and adsorption rate of Cr reached 1.621 mg/g and 97. 3% ( C-ABC) and 1. 615 mg/g and 96. 9% ( C-CBC) respectively. Chitosan and biochar have better recovery performance. Langmuir isothermal model and quasi-second order kinetic model can better describe the adsorption process. Thermodynamic studies show that Cr adsorption by chitosan-biochar is a spontaneous, endothermic and irreversible process. Chitosan-biochar could be used as a potential candidate biomass adsorbent for heavy metal pollutants in electroplating wastewater. [ABSTRACT FROM AUTHOR]