Amphipathic Regulation Of Cottonseed Protein With The Conjugation Of Bayberry Tannin For Efficient Surface Decontamination Of Uranium

Abstract

Radioactive substances (Uranium) on the human body or facility surfaces are easy to diffuse in nuclear activity, posing a severe threat to ecological security and human health, especially for personnel working in and around uranium mining and nuclear facilities. In this work, a green protein-based surfactant was synthesized using the free-radical conjugating method to graft bayberry tannin (BT) onto cottonseed protein (CPI) for regulating its amphipathy and removing uranyl ions (UO₂²⁺) in both aqueous environments and solid surfaces. FTIR, CD spectroscopy, intrinsic fluorescence, conductometric titration, and SEM-EDX characterization techniques confirmed the successful covalent conjugation of BT onto CPI, inducing unfolding, conformational changes, and enhanced hydrophilicity of CPI. Thus, leading to improved foaming and emulsifying properties. Notably, the surfactant exhibited high efficiency in UO₂²⁺ removal and selectivity from an aqueous environment, achieving a removal rate of 93 % within 30 minutes and a maximum adsorption capacity of 310.15 mg/g. Additionally, it also demonstrated effectiveness in decontaminating different simulated uranium-contaminated solid surfaces. The synergistic interaction between BT’s phenolic-hydroxyl groups and CPI’s structural versatility and functional groups facilitated the effective UO₂²⁺ complexation. This study demonstrates the feasibility of using agro-industrial waste-derived CPI-BT as an eco-friendly, sustainable, and cost-effective alternative to synthetic surfactants for mitigating uranium contamination in environments near uranium mining operations and nuclear facilities.