College of Chemistry and Chemical Engineering, Qinghai Normal University, No. 38, Wusi West Road, Chengxi District, Xining City, 810008, Qinghai, China.
Environ Sci Pollut Res Int. 2022 Dec;29(59):88882-88893. doi: 10.1007/s11356-022-21971-8. Epub 2022 Jul 16.
Radioactive iodine in nuclear waste is increasingly harmful to the human body and the environment because of its strong radioactivity, high fluidity, easy solubility in water, and long half-life. It is very important to find clean and economical materials to recover and fix radioactive iodine. In this paper, the amino-metal-organic framework was covalently modified to obtain composite materials to improve the recycling of iodine in the environment. These adsorbents are used to adsorb iodine in water, showing outstanding adsorption performance. The adsorption data are in good agreement with the Langmuir isothermal adsorption model and pseudo-second-order kinetic model, indicating that the adsorption process is mainly monolayer adsorption and chemical adsorption. The two materials showed selective adsorption capacity for iodine in the solution containing multiple competing ions. The adsorption capacity of the covalently modified composite increased from 949.52 to 2157.44 mg/g. Compared with the amino-metal-organic framework, the modified composite contains more electron-rich groups as active sites, and forms charge transfer compounds with iodine to realize chemical adsorption. Through the simulated adsorption of ultra-high-pressure micro-jet, the material has certain working ability under high pressure, which provides a theoretical basis for the future recovery and utilization of iodine under high pressure.
核废料中的放射性碘因其强放射性、高流动性、易溶于水和长半衰期而对人体和环境造成越来越大的危害。寻找清洁、经济的材料来回收和固定放射性碘非常重要。本文通过共价修饰氨基金属有机骨架，得到复合材料，以提高环境中碘的回收。这些吸附剂被用于吸附水中的碘，表现出优异的吸附性能。吸附数据与 Langmuir 等温吸附模型和拟二级动力学模型吻合较好，表明吸附过程主要是单层吸附和化学吸附。这两种材料对含有多种竞争离子的溶液中的碘表现出选择性吸附能力。共价修饰复合材料的吸附容量从 949.52 增加到 2157.44 mg/g。与氨基金属有机骨架相比，修饰复合材料含有更多富电子基团作为活性位点，并与碘形成电荷转移化合物，实现化学吸附。通过超高压微射流的模拟吸附，该材料在高压下具有一定的工作能力，为未来高压下碘的回收和利用提供了理论依据。
