Boudjema Lotfi, Assaf Marwa, Salles Fabrice, Gassin Pierre-Marie, Martin-Gassin Gaelle, Zajac Jerzy
ICGM, Univ Montpellier, CNRS, ENSCM, Montpellier, France.
Molecules. 2024 Jun 21;29(13):2952. doi: 10.3390/molecules29132952.
The impact of solvents on the efficiency of cationic dye adsorption from a solution onto protonated Faujasite-type zeolite (FAU-Y) was investigated in the prospect of supporting potential applications in wastewater treatment or in the preparation of building blocks for optical devices. The adsorption isotherms were experimentally determined for methylene blue (MB) and auramine O (AO) from single-component solutions in water and in ethanol. The limiting dye uptake (saturation capacity) was evaluated for each adsorption system, and it decreased in the order of MB-water > AO-water > AO-ethanol > MB-ethanol. The mutual distances and orientations of the adsorbed dye species, and their interactions with the oxygen sites of the FAU-Y framework, with the solvent molecules, and among themselves were inferred from Monte Carlo simulations and subsequently utilized to rationalize the observed differences in the saturation capacity. The dye-solvent competition and the propensity of the dyes to form compact pi-stacked dimers were shown to play an important role in establishing a non-uniform distribution of the adsorbed species throughout the porous space. The two effects appeared particularly strong in the case of the MB-water system. The necessity of including solvent effects in modeling studies is emphasized.
从支持废水处理或光学器件构建块制备等潜在应用的角度出发，研究了溶剂对阳离子染料从溶液吸附到质子化八面沸石型沸石（FAU-Y）上的效率的影响。通过实验测定了亚甲基蓝（MB）和金胺O（AO）在水和乙醇中的单组分溶液的吸附等温线。评估了每个吸附系统的极限染料吸附量（饱和容量），其递减顺序为MB-水＞AO-水＞AO-乙醇＞MB-乙醇。通过蒙特卡罗模拟推断了吸附染料物种的相互距离和取向，以及它们与FAU-Y骨架的氧位点、溶剂分子之间以及它们自身之间的相互作用，随后用于合理化观察到的饱和容量差异。染料-溶剂竞争以及染料形成紧密π堆积二聚体的倾向在整个多孔空间中吸附物种的非均匀分布的形成中起着重要作用。这两种效应在MB-水体系中尤为明显。强调了在建模研究中纳入溶剂效应的必要性。
