Matskevich Anna I, Maslov Konstantin V, Prokudina Veronika A, Churakova Daria D, Korochencev Vladimir V, Slabko Oleg Yu, Eliseenko Evgenij A, Tokar' Eduard A
Institute of Natural Sciences and Technosphere Safety, Sakhalin State University, 693000 Yuzhno-Sakhalinsk, Russia.
Institute of High Technologies and Advanced Materials, Far Eastern Federal University, 690922 Vladivostok, Russia.
Gels. 2024 Dec 27;11(1):14. doi: 10.3390/gels11010014.
A new composite material with enhanced sorption-selective properties for uranium recovery from liquid media has been obtained. Sorbents were synthesized through a polycondensation reaction of a mixture of 4-amino-N'-hydroxy-1,2,5-oxadiazole-3-carboximidamide (hereinafter referred to as amidoxime) and SiO in an environment of organic solvents (acetic acid, dioxane) and highly porous SiO. To establish optimal conditions for forming the polymer sorption-active part and the synthesis as a whole, a series of composite adsorbents were synthesized with varying amidoxime/matrix ratios (35/65, 50/50, 65/35). The samples were characterized with FT-IR, XRD, SEM, EDX, XRFES spectroscopy and TGA. Under static conditions of uranium sorption, the dependence of the efficiency of radionuclide recovery from mineralized solutions of various acidities on the ratio of the initial components was established. In the pH range from 4 to 8 (inclusive), the uranium removal efficiency exceeds 95%, while the values of the distribution coefficients (Kd) exceed 10 cmg. It was demonstrated that an increase in the surface development of the sorbents enhances such kinetic parameters of uranium sorption as diffusion rate by 10-20 times compared to non-porous materials. The values of the maximum static capacity exceed 700 mg g. The enhanced availability of adsorption centers, achieved through the use of a porous SiO matrix, significantly improves the kinetic parameters of the adsorbents. A composite with optimal physicochemical and sorption properties (amidoxime/matrix ratio of 50/50) was examined under dynamic conditions of uranium sorption. It was found that the maximum dynamic sorption capacity of porous materials is four times greater compared to that of a non-porous adsorbent Se-init. The effective filter cycle exceeds 3200 column volumes-twice that of an adsorbent with a monolithic surface. These results indicate the promising potential of the developed materials for uranium sorption from liquid mineralized media under dynamic conditions across a wide pH range.
已获得一种具有增强吸附选择性的新型复合材料，用于从液体介质中回收铀。通过4-氨基-N'-羟基-1,2,5-恶二唑-3-甲脒（以下简称偕胺肟）与SiO在有机溶剂（乙酸、二氧六环）和高孔隙率SiO环境中的缩聚反应合成吸附剂。为了确定形成聚合物吸附活性部分及整个合成过程的最佳条件，合成了一系列偕胺肟/基体比例不同（35/65、50/50、65/35）的复合吸附剂。采用傅里叶变换红外光谱（FT-IR）、X射线衍射（XRD）、扫描电子显微镜（SEM）、能谱仪（EDX）、X射线荧光光谱仪（XRFES）和热重分析（TGA）对样品进行表征。在铀吸附的静态条件下，确定了不同酸度矿化溶液中放射性核素回收效率对初始组分比例的依赖性。在pH值为4至8（含）的范围内，铀去除效率超过95%，而分配系数（Kd）值超过10 cmg。结果表明，与无孔材料相比，吸附剂表面展开程度的增加使铀吸附的扩散速率等动力学参数提高了10至20倍。最大静态容量值超过700 mg/g。通过使用多孔SiO基体实现的吸附中心更高的可及性显著改善了吸附剂的动力学参数。在铀吸附的动态条件下，对具有最佳物理化学和吸附性能（偕胺肟/基体比例为50/50）的复合材料进行了研究。发现多孔材料的最大动态吸附容量比无孔吸附剂Se-init大四倍。有效过滤周期超过3200柱体积，是具有整体表面的吸附剂的两倍。这些结果表明，所开发的材料在宽pH范围内从液体矿化介质中动态吸附铀具有广阔的应用前景。
