⁶⁰Coγ activation of Cladophora rupestris biomass functional groups and its effect on Pb²⁺ adsorption

To investigate the modification of Pb²⁺ adsorption of the functional groups of Cladophora rupestris (C. rupestris) biomass by gamma radiation (⁶⁰Coγ-ray), the interface structure, chemical properties, adsorption behaviors, and Pb²⁺ adsorption mechanisms of C. rupestris biomass were investigated after irradiation with varying doses of ⁶⁰Coγ-ray. The results indicate that ⁶⁰Coγ-ray significantly changed the surface characteristics and interfacial chemistry of the C. rupestris biomass.This led to fracturing and fragmentation that produced a larger specific surface area and more abundant pore structure, increasing the electronegativity in the C. rupestris biomass. The theoretical Pb²⁺ adsorption capacity increased significantly (2.6-2.9 times) after ⁶⁰Coγ-ray irradiation. ⁶⁰Coγ-ray caused preferential degradation of protein components in the dissolved organic matter of the C. rupestris biomass, and protein deamination increased the absorption sites of cations. In the C. rupestris biomass, ⁶⁰Coγ-ray altered the elemental composition and functional groups, particularly the carbon- and oxygen-containing functional groups, to improve Pb²⁺ adsorption. In conclusion, ⁶⁰Coγ-ray can activate the functional groups of C. rupestris biomass and improve their Pb²⁺ adsorption sites. This study provides new insight into modification of biomass materials for enhanced removal of heavy metals from waterbodies.