Haggag El-Sayed A, Tohamy Hebat-Allah S, Mahmoud Alaa El Din, El-Sakhawy Mohamed, Salem Amany R
Semi-Industrial Experiments, Production Sector, Nuclear Materials Authority, P.O. Box 530, El-Maadi, Cairo, Egypt.
Cellulose and Paper Department, National Research Centre, 33 El Bohouth Str., P.O. 12622, Dokki Giza, Egypt.
Int J Biol Macromol. 2025 Sep;321(Pt 3):145666. doi: 10.1016/j.ijbiomac.2025.145666. Epub 2025 Jul 1.
In this study, a novel acrylamide Schiff base hydrogel was synthesized as an efficient adsorbent for uranium removal from contaminated environments. The hydrogel was characterized using a range of techniques, and its adsorption performance was systematically evaluated through batch experiments that investigated the effects of pH, contact time, initial ion concentration, adsorbent dosage, and temperature. Under optimized conditions, pH 4.0, 120 min, 70 mg adsorbent, 298 K, and 100 mg L U(VI), a uranyl ion removal efficiency of 99.92 % was achieved. Notably, using a lower adsorbent dose (5 mg) resulted in a maximum adsorption capacity of 148 mg g. Adsorption isotherm and kinetic studies revealed that the data best fit the Langmuir model (R = 0.98) and pseudo-second-order kinetics (R = 0.99), indicating a monolayer chemisorption mechanism; the Langmuir model also provided a maximum adsorption capacity of 159.23 mg g. Thermodynamic analysis confirmed that the adsorption process was spontaneous and exothermic. The hydrogel further demonstrated excellent selectivity and resistance to interference from coexisting ions. Optimization using Central Composite Design (CCD) within the framework of Response Surface Methodology (RSM) enabled the development of a predictive polynomial model to assess and optimize the key operational parameters. Finally, the practical applicability of the hydrogel was demonstrated through successful remediation of a real water sample.
在本研究中，合成了一种新型丙烯酰胺席夫碱水凝胶，作为从受污染环境中去除铀的高效吸附剂。使用一系列技术对该水凝胶进行了表征，并通过批量实验系统评估了其吸附性能，这些实验研究了pH值、接触时间、初始离子浓度、吸附剂用量和温度的影响。在优化条件下，即pH值4.0、120分钟、70毫克吸附剂、298 K和100毫克/升U(VI)，铀酰离子去除效率达到99.92%。值得注意的是，使用较低的吸附剂剂量(5毫克)时，最大吸附容量为148毫克/克。吸附等温线和动力学研究表明，数据最符合朗缪尔模型(R = 0.98)和准二级动力学(R = 0.99)，表明为单层化学吸附机制；朗缪尔模型还给出了159.23毫克/克的最大吸附容量。热力学分析证实吸附过程是自发的且放热的。该水凝胶还表现出优异的选择性和对共存离子干扰的抗性。在响应面法(RSM)框架内使用中心复合设计(CCD)进行优化，能够开发出一个预测多项式模型来评估和优化关键操作参数。最后，通过成功修复实际水样证明了该水凝胶在实际中的适用性。
