Park Jinkyu, Bae Jaeyeon, Jin Kangwoo, Park Jinhee
Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, 989-111, Daedeok-daero, Yuseong-gu, Daejeon, 34057, South Korea.
Department of Emerging Materials Science, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungang-daero, Dalseong-gun, Daegu, 42988, South Korea.
J Hazard Mater. 2019 Jun 5;371:243-252. doi: 10.1016/j.jhazmat.2019.03.007. Epub 2019 Mar 1.
Carboxylate-functionalized organic nanocrystals (ONCs) derived from perylene diimide or naphthalene diimide were synthesized and carefully characterized as novel high-capacity uranium (U(VI)) sorbents. Adsorption studies using uranyl ions demonstrated that the carboxyl and hydroxyl groups on the surface of the ONCs play pivotal roles in U(VI) adsorption. ONCs formed from the condensation of perylene dianhydride and aminoisophthalic acid exhibit very high U(VI) adsorption capacities of 1393 mg g comparable to the highest capacity ever reported. The adsorption kinetics of the ONCs were found to obey the second-order model, indicating that chemisorption is the rate-determining step for U(VI) adsorption by these materials. Furthermore, the perylene-based ONC containing imidazole exhibited no pH dependency upon the U(VI) adsorption and the naphthalene-based ONC was able to remove up to 97.5% U(VI) from simulated nuclear industrial effluent containing many competing elements. These findings will facilitate the development of high-performance organic U(VI) sorbents with high densities of adsorption sites.
合成了源自苝二酰亚胺或萘二酰亚胺的羧基官能化有机纳米晶体（ONCs），并将其作为新型高容量铀（U(VI)）吸附剂进行了详细表征。使用铀酰离子进行的吸附研究表明，ONCs表面的羧基和羟基在U(VI)吸附中起关键作用。由苝四甲酸二酐和氨基间苯二甲酸缩合形成的ONCs表现出非常高的U(VI)吸附容量，可达1393 mg g，与报道过的最高容量相当。发现ONCs的吸附动力学符合二级模型，这表明化学吸附是这些材料吸附U(VI)的速率决定步骤。此外，含咪唑的苝基ONC对U(VI)的吸附不依赖于pH值，萘基ONC能够从含有多种竞争元素的模拟核工业废水中去除高达97.5%的U(VI)。这些发现将有助于开发具有高密度吸附位点的高性能有机U(VI)吸附剂。
