"Petru Poni" Institute of Macromolecular Chemistry, Aleea Grigore Ghica Voda 41A, 700487, Iasi, Romania.
"Petru Poni" Institute of Macromolecular Chemistry, Aleea Grigore Ghica Voda 41A, 700487, Iasi, Romania.
Int J Biol Macromol. 2019 Feb 15;123:587-599. doi: 10.1016/j.ijbiomac.2018.11.080. Epub 2018 Nov 15.
Herein, we report a new composite magnetic-adsorbent made of doped spinel ferrite (15%) dispersed throughout a matrix of chitosan (CS) cross-linked with glutaraldehyde (GA). The composite material was well characterized by using instrumental methods of physical-chemical analysis (SEM, EDX, FTIR and VSM). The produced adsorbent was applied for the removal of Acid Orange 7 (AO7) dye from aqueous solutions. Aspects of adsorption kinetics, isotherms and thermodynamics were detailed. According to the Dubinin-Radushkevich (D-R) isotherm, the mean free energy of adsorption ranged from 14.37 to 16.59 (kJ/mol), suggesting ion-exchange dominating phenomena. In addition, we developed an artificial neural network (ANN) model to explore extensively the effects of factors on the adsorption performance. The coupling of ANN model with a genetic algorithm provided optimal conditions of adsorption. A maximal color removal efficiency of 98.01% was observed experimentally under optimal conditions (pH 2.51, sorbent dosage 3.88 g/L, initial dye concentration 25.3 mg/L, contact time 204 min). To unveil interaction mechanism, we employed molecular docking simulations. Computational outcomes suggested the formation of hydrophobic contacts and hydrogen bonds between AO7 dye molecule and CS-GA receptor. Molecular docking results agreed with the D-R isotherm findings, highlighting that electrostatic forces were greater than Van-der-Waals interactions.
本文报道了一种新型的磁性复合吸附剂，由掺杂尖晶石型铁氧体（15%）分散在壳聚糖（CS）基质中，并用戊二醛（GA）交联而成。采用物理化学分析仪器方法（SEM、EDX、FTIR 和 VSM）对复合材料进行了全面表征。所制备的吸附剂用于从水溶液中去除酸性橙 7（AO7）染料。详细研究了吸附动力学、等温线和热力学等方面。根据 Dubinin-Radushkevich（D-R）等温线，吸附的平均自由能范围为 14.37 至 16.59（kJ/mol），表明离子交换起主导作用。此外，我们还开发了人工神经网络（ANN）模型，广泛探索了各种因素对吸附性能的影响。ANN 模型与遗传算法的耦合提供了吸附的最佳条件。在最佳条件下（pH 2.51、吸附剂用量 3.88 g/L、初始染料浓度 25.3 mg/L、接触时间 204 min），实验观察到最大去除效率为 98.01%。为了揭示相互作用机制，我们进行了分子对接模拟。计算结果表明，AO7 染料分子与 CS-GA 受体之间形成了疏水接触和氢键。分子对接结果与 D-R 等温线的发现一致，表明静电相互作用大于范德华相互作用。
