School of Materials Engineering, Changshu Institute of Technology, 215500, China; Suzhou Key Laboratory of Functional Ceramic Materials, Changshu Institute of Technology, Changshu, 215500, China; School of Chemical Engineering & Technology, China University of Mining and Technology, Xuzhou, Jiangsu, 221116, China.
School of Materials Engineering, Changshu Institute of Technology, 215500, China.
Environ Pollut. 2021 Dec 1;290:118002. doi: 10.1016/j.envpol.2021.118002. Epub 2021 Aug 19.
The influence of intercalated anions on the structure and composition of green rusts supplies a theoretical possibility for the investigation of the structural modification of Fe/Fe (oxyhydr)oxide materials. β-Cyclodextrin was intercalated into the mixed-valent iron-based hydroxide layers to synthesize new green rust materials (β-CD GRs), pursuing high-capacity uranium (U) sorption. The molar ratios of Fe to Fe and the molar ratios of β-CD GR to Fe + Fe had a significant effect on the synthesis of β-CD GRs. The synthesis process was further optimized by the quadric predictor and desirability function in a central composite design in combination. Both strong acidity and alkalinity were harmful to the adsorption of β-CD GRs towards U. The pseudo-first-order kinetic model and Langmuir isotherm model were appropriate in fitting the whole adsorption process. The maximum monolayer adsorption capacity of β-CD GRs was 2548.61 mg/g. The presence of mimic groundwater constituents explicitly deteriorated the interaction between β-CD GR and U species. Nanoscale nodules and particles were formed on the β-CD GR after the adsorption experiments. The peaks at 1159 and 609 cm vanished with the band at 1103 cm being left-shifted to 1117 cm in the FTIR spectra of β-CD GR during the heterogeneous process. The intercalation of β-CD brought obvious enhancement of U species sorption to the GR material, which was combinedly driven by several reaction pathways and different from the unmodified GRs.
插层阴离子对绿锈的结构和组成的影响为研究 Fe/Fe（氧氢）氧化物材料的结构改性提供了理论可能性。β-环糊精被插入到混合价铁基氢氧化物层中，以合成新的绿锈材料（β-CD GRs），以追求高容量的铀（U）吸附。Fe 与 Fe 的摩尔比和β-CD GR 与 Fe+Fe 的摩尔比对β-CD GRs 的合成有显著影响。通过二次预测器和中心组合设计中的适宜性函数组合进一步优化了合成过程。强酸性和强碱性都不利于β-CD GRs 对 U 的吸附。伪一阶动力学模型和 Langmuir 等温线模型都适合于拟合整个吸附过程。β-CD GRs 的最大单层吸附容量为 2548.61mg/g。模拟地下水中组分的存在明显恶化了β-CD GR 与 U 物种之间的相互作用。在吸附实验后，β-CD GR 上形成了纳米级结节和颗粒。在非均相过程中，β-CD GR 的 FTIR 光谱中，1159 和 609cm 的峰消失，而 1103cm 的带向左移动至 1117cm。β-CD 的插层明显增强了 U 物种对 GR 材料的吸附，这是由几种反应途径共同驱动的，与未改性的 GRs 不同。
