Azizi Amine El, Maliki Soundouss, Hamidallah Konouz, Chahid Ayoub, Harouachi Hanane El, Zourif Ali, Mansori Mohammed, Loutou Mohamed
Université Mohammed Premier Oujda, Faculté Pluridisciplinaire de Nador, Nador, Morocco.
Hassan I University, Faculty of Sciences and Techniques, BP. 577, 26000, Settat, Morocco.
Environ Sci Pollut Res Int. 2025 Jun;32(26):15695-15715. doi: 10.1007/s11356-025-36627-6. Epub 2025 Jun 14.
This study aims to explore the potential of natural Moroccan clay (NMC) as a cost-effective and sustainable adsorbent for removing methylene blue from aqueous solutions, addressing the global challenge of water pollution through an innovative integration of experimental and theoretical approaches. By combining advanced characterization techniques and computational modeling, the study offers novel insights into the adsorption mechanisms of NMC. Characterization of NMC using X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, X-ray fluorescence, and point-of-zero charge determination revealed a predominant montmorillonite composition with significant amounts of silica (61.33%) and alumina (13.33%). Adsorption experiments were conducted using varying parameters such as solid/liquid ratio, initial dye concentration, and contact time to identify suitable conditions for maximum adsorption capacity. The maximum adsorption capacity reached 315.05 mg/g under the tested conditions. Kinetic studies demonstrated that the adsorption follows kinetics best described by the Elovich and intra-particle diffusion models, indicating chemisorption on heterogeneous surfaces coupled with intra-particle mass transfer limitations. Isotherm analysis showed the best fit with the Langmuir model (R = 0.9971), suggesting monolayer adsorption. Thermodynamic parameters (ΔG°, ΔH°, and ΔS°) confirmed the spontaneous and endothermic nature of the process. Density functional theory calculations provided insights into methylene blue's electronic properties and reactivity, with a HOMO-LUMO energy gap of 0.35 eV indicating a favorable interaction potential. Monte Carlo simulations revealed strong adsorption energies ranging from - 123.24 to - 133.01 kJ/mol, confirming the stability of MB-NMC interactions. This comprehensive study establishes NMC as a promising, eco-friendly solution for wastewater treatment, providing a detailed mechanistic understanding of its adsorption performance.
本研究旨在探索天然摩洛哥黏土（NMC）作为一种经济高效且可持续的吸附剂，用于从水溶液中去除亚甲基蓝的潜力，通过实验和理论方法的创新整合来应对全球水污染挑战。通过结合先进的表征技术和计算建模，该研究为NMC的吸附机制提供了新的见解。使用X射线衍射、傅里叶变换红外光谱、扫描电子显微镜、热重分析、X射线荧光和零电荷点测定对NMC进行表征，结果显示其主要成分为蒙脱石，含有大量的二氧化硅（61.33%）和氧化铝（13.33%）。采用不同参数（如固液比、初始染料浓度和接触时间）进行吸附实验，以确定实现最大吸附容量的合适条件。在测试条件下，最大吸附容量达到315.05 mg/g。动力学研究表明，吸附遵循由埃洛维奇模型和颗粒内扩散模型最佳描述的动力学，表明在异质表面上的化学吸附以及颗粒内传质限制。等温线分析表明与朗缪尔模型拟合最佳（R = 0.9971），表明为单层吸附。热力学参数（ΔG°、ΔH°和ΔS°）证实了该过程的自发性和吸热性质。密度泛函理论计算提供了亚甲基蓝电子性质和反应性的见解，其HOMO-LUMO能隙为0.35 eV，表明具有良好的相互作用潜力。蒙特卡罗模拟揭示了从-123.24至-133.01 kJ/mol的强吸附能，证实了MB-NMC相互作用的稳定性。这项全面的研究确立了NMC作为一种有前途的、生态友好的废水处理解决方案，对其吸附性能提供了详细的机理理解。
