Uranium is the important nuclear fuel and its effective adsorption using low-cost materials is meaningful to environmental protection and sustainable development of nuclear energy. In this study, green and economical reed straw-derived biochar (RBC) was prepared by hydrothermal carbonization method using low-cost reed straw as feedstocks and citric acid as catalysts for uranium(VI) removal. RBC possessed larger pores and more oxygen-containing functional groups, providing more abundant adsorption sites for uranyl ions. RBC adsorbed uranium pH-dependently, spontaneously and endothermically, and pseudo-second-order kinetics and the Langmuir model could adequately describe the adsorption process. This work highlighted a feasible synthesis strategy of biochar for radioactive contaminants removal.

铀是重要的核燃料，利用低成本材料对其进行有效吸附，对环境保护和核能可持续发展具有重要意义。本研究以低成本的芦苇秸秆为原料，柠檬酸为催化剂去除铀（VI），采用水热炭化法制备绿色经济的芦苇秸秆衍生生物炭（RBC）。RBC具有较大的孔隙和更多的含氧官能团，为铀酰离子提供了更丰富的吸附位点。RBC 吸附铀的 pH 依赖性、自发性和吸热性以及准二级动力学和 Langmuir 模型可以充分描述吸附过程。这项工作强调了一种可行的生物炭去除放射性污染物的合成策略。