Luofu Min,Jingying Duan,Chuan Song,Yanan Chen,Wen Zhang,Yuxin Wang
Layered double hydroxides (LDHs) intercalated with tunable anionic species are finding increasingly wide applications. While LDHs with intercalated CO32− anions (LDH-CO3) are usually synthesized to achieve high crystallinity, the substitution of the intercalated CO32− with other desired anions is rather difficult because of the ultra-high affinity of CO32− to LDHs’ main plates. Herein, we report a novel and facile method to overcome this difficulty. LDH-CO3 is decarbonated via submerging in a carbonated NaCl solution with CO2 bubbling. Complete deintercalation of CO32− is achieved quickly without damaging the main plates, i.e., the hydroxide layers, even in the case of Mg2Al-LDH-CO3 having the most stable CO32− anions. It is shown that carbonic acid H2CO3 in the salt solution reacts with intercalated CO32− to form bicarbonate (HCO3−), which exhibits a much lower affinity to the main plates and thus is easily substituted by chloride ions (Cl−) from the salt solution.
Constantin Muhire,Behery Realy,Xiyan Xu,Dagang Li,Niu Zhang,Dongxiang Zhang
In this work, a novel inorganic-organic Bi/La-C-oxide material for iodine vapor capture in conditions of high temperature, mostly encountered during the reprocessing of the spent nuclear fuel, was synthesized. Bi/La-C-oxide (Bi/La=1, 300 °C) was synthesized using a new approach that allowed the non-decarbonization of used fuels, which instead made a framework with the core of Bi/La oxide to form a hybrid material, which exhibited a fast iodine uptake with a capacity of 1339.64 mg·g −1 at 18 h and 1301.47 mg·g −1 after 26 h at 200 °C, respectively. Notably, Bi/La-C-oxide (Bi/La=1, 300 °C) owed the high iodine-adsorbing ability mainly from its structure made of tetragonal units of Bi 1.92 La 0.08 O 3 linked together with esters to form a polyesterified Bi/La-C-oxide framework. The thermal stability analysis of the materials before and after iodine capture showed high thermal stabilities, proving their ability to withstand real-field high-temperature conditions. ZnO was used to consolidate the iodine wastes to avoid post-sorption secondary pollution, and the iodine leaching rate was minimized to 1.143 × 10 −3 g·(m 2 ·day) −1 after 7 days of product consistency test-A.
危险品化学品经营许可证（带存储）