Hamza Mohammed F, Fouda Amr, Elwakeel Khalid Z, Wei Yuezhou, Guibal Eric, Hamad Nora A
Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured Materials, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China.
Nuclear Materials Authority, POB 530, El-Maadi, Cairo 11884, Egypt.
Molecules. 2021 Mar 29;26(7):1920. doi: 10.3390/molecules26071920.
The development of new materials is needed to address the environmental challenges of wastewater treatment. The phosphorylation of guar gum combined with its association to chitosan allows preparing an efficient sorbent for the removal of U(VI) from slightly acidic solutions. The incorporation of magnetite nanoparticles enhances solid/liquid. Functional groups are characterized by FTIR spectroscopy while textural properties are qualified by N adsorption. The optimum pH is close to 4 (deprotonation of amine and phosphonate groups). Uptake kinetics are fast (60 min of contact), fitted by a pseudo-first order rate equation. Maximum sorption capacities are close to 1.28 and 1.16 mmol U g (non-magnetic and magnetic, respectively), while the sorption isotherms are fitted by Langmuir equation. Uranyl desorption (using 0.2 M HCl solutions) is achieved within 20-30 min; the sorbents can be recycled for at least five cycles (5-6% loss in sorption performance, complete desorption). In multi-component solutions, the sorbents show marked preference for U(VI) and Nd(III) over alkali-earth metals and Si(IV). The zone of exclusion method shows that magnetic sorbent has antibacterial effects against both Gram+ and Gram- bacteria, contrary to non-magnetic material (only Gram+ bacteria). The magnetic composite is highly promising as antimicrobial support and for recovery of valuable metals.
需要开发新型材料来应对废水处理中的环境挑战。瓜尔胶的磷酸化及其与壳聚糖的结合使得能够制备一种高效吸附剂，用于从微酸性溶液中去除U(VI)。磁铁矿纳米颗粒的掺入增强了固液分离效果。通过傅里叶变换红外光谱对官能团进行表征，同时通过N吸附对结构性质进行鉴定。最佳pH接近4（胺基和膦酸根基团去质子化）。吸附动力学很快（接触60分钟），符合准一级速率方程。最大吸附容量分别接近1.28和1.16 mmol U g（分别为非磁性和磁性吸附剂），吸附等温线符合朗缪尔方程。铀酰解吸（使用0.2 M HCl溶液）在20 - 30分钟内完成；吸附剂可循环使用至少五个周期（吸附性能损失5 - 6%，完全解吸）。在多组分溶液中，吸附剂对U(VI)和Nd(III)的偏好明显高于碱土金属和Si(IV)。排阻区带法表明，与非磁性材料（仅对革兰氏阳性菌有作用）不同，磁性吸附剂对革兰氏阳性菌和革兰氏阴性菌均有抗菌作用。这种磁性复合材料作为抗菌载体和回收有价金属具有很大的潜力。
