Abara Hajar, Raissouni Jaber, Saadani Hajar, El Hachmi Abdelhadi, Hadri Mohamed, Draoui Khalid
IMED-LAB, FS, Abdelmalek Essaadi University, Faculty of Sciences, 93002 Tetouan, Morocco.
Physico-chemistry of Materials Team, Department of Chemistry, Faculty of Science, Abdelmalek Essaadi University, 93002 Tetouan, Morocco.
Int J Biol Macromol. 2025 Sep;321(Pt 4):146481. doi: 10.1016/j.ijbiomac.2025.146481. Epub 2025 Aug 5.
In this study, we created a multifunctional adsorbent, F-(clay/alg@Fe-Ni), by modifying natural clay with alginate. The ionic gelation of alginate using Ca ions was followed by the introduction of (FeNi) nanoparticles through the chemical reduction of the resulting gel. The prepared adsorbent was then characterized and utilized for the uptake of Pb and malachite green (MG) from water. XRD revealed changes in peak intensities and interlayer spacing, indicating interactions between the clay and alginate. Additionally, FTIR analysis demonstrated the existence of various functions on the composite surface, such as -OH and -COO- groups. Furthermore, (pH), (TGA/DTG), and (SEM) analyses validated the modifications made to the clay surface. The development of additional adsorption sites and functional groups based on F-(clay/alg@Fe-Ni) significantly improved the adsorption performance of Pb and malachite green (MG) compared to natural clay. The best-fitting results were obtained using the pseudo-second-order and Langmuir adsorption models, with a maximum adsorption capacity of 189.08 mg/g for Pb and 365.31 mg/g for MG. According to the calculated thermodynamic factors, the adsorption can be defined as physical and endothermic. DFT simulations were used to evaluate the electronic parameters influencing the adsorption of Pb ions and Malachite Green (MG) dye on clay surfaces. Advanced topological analyses, including LOL, ELF, VMD, and RDG, were performed in the liquid phase using Multiwfn. Monte Carlo simulations provided insights into molecular interactions, highlighting the role of electrostatic forces and hydrogen bonding in enhancing adsorption efficiency. Theoretical studies confirmed the high reactivity of MG cations, facilitating strong adsorption. Monte Carlo searches identified optimal adsorption configurations on unmodified and modified kaolinite and clinochlore surfaces, revealing that Alg@Fe-Ni significantly improved adsorption, particularly on the (100) surface. Hirshfeld surface analysis further validated the predominant adsorption mechanisms. Overall, integrating clay, alginate, and FeNi nanoparticles resulted in an efficient and cost-effective method for heavy metals and dyes removal, overcoming solid/liquid separation challenges.
在本研究中，我们通过用藻酸盐改性天然粘土，制备了一种多功能吸附剂F-(粘土/藻酸盐@铁-镍)。先用钙离子使藻酸盐发生离子凝胶化，然后通过对所得凝胶进行化学还原引入(铁镍)纳米颗粒。然后对制备的吸附剂进行表征，并用于从水中吸附铅和孔雀石绿(MG)。X射线衍射(XRD)显示峰强度和层间距发生变化，表明粘土与藻酸盐之间存在相互作用。此外，傅里叶变换红外光谱(FTIR)分析表明复合材料表面存在各种官能团，如-OH和-COO-基团。此外，(pH)、(热重分析/微商热重分析)和(扫描电子显微镜)分析验证了对粘土表面所做的改性。与天然粘土相比，基于F-(粘土/藻酸盐@铁-镍)的额外吸附位点和官能团的形成显著提高了对铅和孔雀石绿(MG)的吸附性能。使用伪二级和朗缪尔吸附模型获得了最佳拟合结果，铅的最大吸附容量为189.08 mg/g，孔雀石绿的最大吸附容量为365.31 mg/g。根据计算的热力学因素，该吸附可定义为物理吸附且为吸热过程。密度泛函理论(DFT)模拟用于评估影响铅离子和孔雀石绿(MG)染料在粘土表面吸附的电子参数。使用Multiwfn在液相中进行了包括定域分子轨道(LOL)、分子中的电子密度分布(ELF)、可视化分子动力学(VMD)和分子间相互作用(RDG)在内的高级拓扑分析。蒙特卡罗模拟提供了分子间相互作用的见解，突出了静电力和氢键在提高吸附效率中的作用。理论研究证实了MG阳离子的高反应活性，促进了强吸附。蒙特卡罗搜索确定了未改性和改性高岭石及斜绿泥石表面上的最佳吸附构型，表明藻酸盐@铁-镍显著提高了吸附性能，特别是在(100)表面。赫希菲尔德表面分析进一步验证了主要的吸附机制。总体而言，将粘土、藻酸盐和铁镍纳米颗粒结合起来，形成了一种高效且经济高效的去除重金属和染料的方法，克服了固液分离的挑战。
