Superior adsorption and removal of industrial dye from aqueous solution via magnetic silver metal-organic framework nanocomposite

The indirect emission had a negative influence on the ecosystem of enormous amounts of harmful dyes into water. Fe₃O₄@Ag-MOF was successfully fabricated to capture Gentine violet (GV)) as a model example of cationic dye from their aqueous solutions was evaluated in this search as a method to eliminate dyes from water contaminants. FTIR, XPS, BET, TGA, SEM, TEM, and XRD have all been used to study this adsorbent in order to determine its structural and chemical characteristics as well as to interpret its binding mechanisms. According to the results of the characterization, the synthesized composite had a size about 45 nm, a surface area of 856.06 m²/g, and considerable magnetic characteristics (66.2 emug⁻¹). Consequently, we created mesoporous surfaces that had a strong ability to interface and absorb GV dye. It is possible to use the pseudo-second order rate equation to characterize the kinetic profile., while the Langmuir equation fits isotherm models. At pH 9, maximum sorption capacities can reach 1.68 mmol.g⁻¹. Additionally, the investigations of temperature profiles indicated the endothermic process and Thermodynamic parameters were discovered as, ΔG°, ΔH° and ΔS° The synthesized adsorbent had an interestingly high reusability of > 92 percent up to the sixth cycle. These findings revealed that a mixture of electrostatic interactions, π-π stacking, hydrogen bonds, and pore filling were involved in the GV adsorption mechanism. Fe₃O₄@Ag-MOF was successful in demonstrating its effectiveness as a point-of-use colour collection candidate from actual dyeing effluents.

大量有害染料间接排放进入水体，对水生生态系统造成了负面影响。本研究成功制备了Fe₃O₄@Ag-MOF，并以阳离子染料龙胆紫（Gentine Violet, GV）为模型污染物，评估了其从水溶液中吸附该染料的性能，以此作为去除水体染料类污染物的可行方案。为明确该吸附剂的结构与化学性质、解析其吸附结合机制，本研究采用傅里叶变换红外光谱（Fourier Transform Infrared Spectroscopy, FTIR）、X射线光电子能谱（X-ray Photoelectron Spectroscopy, XPS）、比表面积测试（Brunauer-Emmett-Teller, BET）、热重分析（Thermogravimetric Analysis, TGA）、扫描电子显微镜（Scanning Electron Microscope, SEM）、透射电子显微镜（Transmission Electron Microscope, TEM）以及X射线衍射（X-ray Diffraction, XRD）对其进行了表征。表征结果显示，所合成的复合吸附剂粒径约为45 nm，比表面积达856.06 m²/g，且具备优异的磁学性能（66.2 emu·g⁻¹）。该材料具有介孔表面结构，可与龙胆紫染料高效结合并实现吸附。动力学吸附过程可通过准二级动力学（pseudo-second order）模型进行拟合，而吸附等温线则符合朗缪尔（Langmuir）模型。在pH为9的条件下，其最大吸附容量可达1.68 mmol·g⁻¹。此外，温度梯度吸附实验结果表明该吸附过程为吸热过程，并得到了吉布斯自由能变（ΔG°）、焓变（ΔH°）与熵变（ΔS°）等热力学参数。所制备的吸附剂具有优异的重复使用性能，在循环至第6次时，吸附效率仍保持在92%以上。上述结果表明，静电相互作用、π-π堆积、氢键作用以及孔道填充共同构成了该材料对龙胆紫染料的吸附机制。Fe₃O₄@Ag-MOF可有效从实际印染废水中捕获染料，证明其可作为现场脱色处理的候选材料。