Khalaf Bayan, Hamed Othman, Jodeh Shehdeh, Hanbali Ghadir, Bol Roland, Dagdag Omar, Samhan Subhi
Department of Chemistry, Faculty of Science, An-Najah National University, P.O. Box 7, Nablus, Palestine.
Institute of Bio and Geosciences, Agrosphere (IBG-3), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
Polymers (Basel). 2021 Jan 30;13(3):450. doi: 10.3390/polym13030450.
In this study, cellulose-based derivatives with heterocyclic moieties were synthesized by reacting cellulose with furan-2-carbonyl chloride (Cell-F) and pyridine-2,6-dicarbonyl dichloride (Cell-P). The derivatives were evaluated as adsorbents for the pesticide tetraconazole from aqueous solution. The prepared adsorbents were characterized by SEM, TGA, IR, and H NMR instruments. To maximize the adsorption efficiency of tetraconazole, the optimum conditions of contact time, pH, temperature, adsorbent dose, and initial concentration of adsorbate were determined. The highest removal percentage of tetraconazole from water was 98.51% and 95% using Cell-F and Cell-P, respectively. Underivatized nanocellulose was also evaluated as an adsorbent for tetraconazole for comparison purpose, and it showed a removal efficiency of about 91.73%. The best equilibrium adsorption isotherm model of each process was investigated based on the experimental and calculated values of Freundlich and Langmuir models. The adsorption kinetics were also investigated using pseudo-first-order, pseudo-second-order, and intra-particle-diffusion adsorption kinetic models. The Van't Hoff plot was also studied for each adsorption to determine the changes in adsorption enthalpy (∆), Gibbs free energy (∆), and entropy (∆). The obtained results showed that adsorption by Cell-F and Cell-P follow the Langmuir adsorption isotherm and the mechanism follows the pseudo-second-order kinetic adsorption model. The obtained negative values of the thermodynamic parameter ∆ (-4.693, -4.792, -5.549 kJ) for nanocellulose, Cell-F, and Cell-P, respectively, indicate a spontaneous adsorption process. Cell-F and Cell-P could be promising absorbents on a commercial scale for tetraconazole and other pesticides.
在本研究中，通过使纤维素与呋喃 - 2 - 甲酰氯（Cell - F）和吡啶 - 2,6 - 二甲酰二氯（Cell - P）反应，合成了具有杂环部分的纤维素基衍生物。这些衍生物被评估为从水溶液中吸附农药戊唑醇的吸附剂。所制备的吸附剂通过扫描电子显微镜（SEM）、热重分析仪（TGA）、红外光谱仪（IR）和核磁共振仪（H NMR）进行表征。为了使戊唑醇的吸附效率最大化，确定了接触时间、pH值、温度、吸附剂剂量和吸附质初始浓度的最佳条件。使用Cell - F和Cell - P从水中去除戊唑醇的最高百分比分别为98.51%和95%。为作比较，未衍生化的纳米纤维素也被评估为戊唑醇的吸附剂，其去除效率约为91.73%。基于Freundlich和Langmuir模型的实验值和计算值，研究了每个过程的最佳平衡吸附等温线模型。还使用伪一级、伪二级和颗粒内扩散吸附动力学模型研究了吸附动力学。还对每次吸附研究了范特霍夫图，以确定吸附焓（∆）、吉布斯自由能（∆）和熵（∆）的变化。所得结果表明，Cell - F和Cell - P的吸附遵循Langmuir吸附等温线，其机制遵循伪二级动力学吸附模型。纳米纤维素、Cell - F和Cell - P的热力学参数∆分别获得负值（-4.693、-4.792、-5.549 kJ），表明吸附过程是自发的。Cell - F和Cell - P在商业规模上可能是用于戊唑醇和其他农药的有前景的吸附剂。
