Thamer Badr M, Aldalbahi Ali, Moydeen A Meera, El-Newehy Mohamed H
Department of Chemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
Department of Chemistry, Faculty of Science, Tanta University, Tanta 31527, Egypt.
Polymers (Basel). 2020 Dec 16;12(12):3002. doi: 10.3390/polym12123002.
The use of some hydrogels as adsorbents for pollutants removal from wastewater is limited due to their high swelling properties and the difficulty in recovering them after the adsorption process. To overcome these problems, a new hydrogel nanocomposite based on chitosan-grafted-polyacrylic acid/oxidized electrospun carbon nanofibers (CT--PAA/O-ECNFs) was prepared by an in situ grafting polymerization process. The prepared hydrogel nanocomposite was used as a novel effective and highly reusable adsorbent for the removal of methylene blue (MB) from polluted water with low cost. The morphology and the structure of CT--PAA/O-ECNFs were investigated by numerous techniques. The effect of incorporating O-ECNFs on the swelling capability of the prepared hydrogel was explored in distillated water and MB solution at normal pH. The effect of parameters including ratio of O-ECNFs, contact time, pH, initial concentration, and temperature on adsorption process were explored. The adsorption isotherm and kinetic were studied by numerous non-linear models. The obtained results confirmed that the incorporation of O-ECNFs into the hydrogel network decreased the swelling capacity and improved its ability towards MB dye removal. The adsorption process depended on the pH value of the dye solution. Additionally, the adsorption and kinetic results were fitted using the Freundlich isotherm model and pseudo second order model (PSO), respectively. Moreover, the new adsorbents can be recycled for at least five cycles keeping its adsorption capacity and can be easily recovered without loss in its initial weight.
一些水凝胶作为从废水中去除污染物的吸附剂，由于其高溶胀性能以及吸附过程后回收困难，其应用受到限制。为克服这些问题，通过原位接枝聚合工艺制备了一种基于壳聚糖接枝聚丙烯酸/氧化电纺碳纳米纤维（CT-PAA/O-ECNFs）的新型水凝胶纳米复合材料。所制备的水凝胶纳米复合材料用作一种新型高效且可高度重复使用的吸附剂，以低成本从污染水中去除亚甲基蓝（MB）。通过多种技术研究了CT-PAA/O-ECNFs的形态和结构。在蒸馏水和正常pH值的MB溶液中探讨了掺入O-ECNFs对所制备水凝胶溶胀能力的影响。研究了包括O-ECNFs比例、接触时间、pH值、初始浓度和温度等参数对吸附过程的影响。通过多种非线性模型研究了吸附等温线和动力学。所得结果证实，将O-ECNFs掺入水凝胶网络中降低了溶胀能力，并提高了其去除MB染料的能力。吸附过程取决于染料溶液的pH值。此外，吸附和动力学结果分别使用Freundlich等温线模型和伪二级模型（PSO）进行拟合。此外，这种新型吸附剂可以循环使用至少五个周期，保持其吸附容量，并且可以轻松回收，初始重量无损失。
