Highly efficient removal of U(VI) by a novel biochar supported with FeS nanoparticles and chitosan composites

The new biochar supported with FeS nanoparticles and chitosan composites (chitosan-FeS@biochar) was prepared and its performance to remove U(VI) ions in aqueous solution was investigated. The results showed that chitosan-FeS@biochar as an efficient adsorbent for treating the environmental pollution was high stability and effective uptake capacity of U(VI). The equilibrium uptake capacity of the chitosan-FeS@biochar at pH 4.16, 100mg/L of U(VI) and 308 K for U(VI) reached 92.45mg/g. The superior adsorption performance could be attributed to: (1) a lot of functional groups were observed on the surface of chitosan-FeS@biochar; (2) FeS nanoparticles could react with U(VI); (3) chitosan prevented FeS nanoparticles aggregation and enhanced their stability and removal efficiency. The suggested reaction mechanism mainly was electrostatic attractive, surface complexation, chemical precipitation and reductive reaction. The chemical stability of chitosan-FeS@biochar was very well. It was also environmentally friendly materials with good reusability in wastewater treatment with low replacement costs. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

The new biochar supported with FeS nanoparticles and chitosan composites shows high efficiency in removing U(VI) ions, with superior adsorption performance attributed to functional groups on its surface, reaction between FeS nanoparticles and U(VI), and the stabilizing effect of chitosan. The suggested reaction mechanism includes electrostatic attractive, surface complexation, chemical precipitation, and reductive reaction. Additionally, the biochar is chemically stable and environmentally friendly, making it a cost-effective option for wastewater treatment.