文献类型：期刊文献

英文题名：Efficient U(Vi) Removal from Aerobic Solution by Synergistic Interaction of Nano Zero-Valent Iron with G-C3n4 and Assessment of Toxicity to Escherichia Coli

作者：Liang, Liping[1,2,3]; Xi, Fenfen[3]; Zhou, Mengfan[2]; Hu, Baowei[2]

机构：[1] School of Environmental Science and Engineering, Changzhou University, Changzhou, 213164, China; [2] School of Life and Environmental Science, Shaoxing University, Shaoxing, 312000, China; [3] College of Chemistry and Chemical Engineering, Donghua University, Shanghai, 201620, China

年份：2024

外文期刊名：SSRN

收录：EI(收录号：20240125540)

语种：英文

外文关键词：Bacteriology - Carbon nitride - Escherichia coli - Iron - Iron compounds - Radioactivity

外文摘要：The graphitic carbon nitride (g-C3N4) supported nano zero-valent iron (nZVI)composites (g-Fe) were synthesized to assess the performance of radioactive U(VI)removal and bacterial inactivation. g-Fe composites (mass ratio was 0.8:1) achievedhigh removal efficiency of U(VI) (91.2%) at pH 6.0 within 60 min under aerobicconditions, while only 7.2% or 22.6% U(VI) were removed by pristine g-C3N4 or nZVI.Effects of operating parameters (pH, temperature, Initial U(VI) concentration, and g-Fedosage) on U(VI) removal were also studied under aerobic conditions. The U(VI)adsorption followed a pseudo-second-order kinetic model, and the adsorption processwas in accordance with the Langmuir adsorption isotherm model. The maximumremoval capacity of U(VI) was 952.38 mg/g at pH = 6.0. The absorbed uraniumspecies on the g-Fe composites were confirmed to be solely U(VI) under aerobicconditions, while both U(VI) and U(IV) species were observed under anaerobicconditions. Hence, adsorption rather than reduction serves as the primary mechanismfor U(VI) removal in aerobic environments. Escherichia coli or Bacillus subtilis could beinactivated by nZVI and g-Fe composites, but the biotoxicity of g-Fe was much lowerthan nZVI. Physical isolation reduced the biotoxicity of nZVI, and the residualbiotoxicity of nZVI after excluding physical contact should be ascribed to oxidativestress or free reactive oxidative species (ROS). The biotoxicity of g-Fe was irrelevant tophysical isolation, proving that oxidative stress or free ROS might dominate theinactivation mechanisms. The g-Fe composite, an eco-friendly, facile, and sustainablematerial, can be developed for U(VI) removal from radioactive wastewater. ? 2024, The Authors. All rights reserved.