Yalova University, Department of Polymer Material Engineering, 77200 Yalova, Turkey.
Yıldız Technical University, Department of Metallurgical and Materials Engineering, 34220 Istanbul, Turkey.
Int J Biol Macromol. 2022 Oct 31;219:273-289. doi: 10.1016/j.ijbiomac.2022.07.238. Epub 2022 Aug 4.
In recent years, polymeric bio-adsorbents offers high removal efficiency, superior adsorption capacity and selectivity against various pollutants in aqueous medium. While designing these adsorbents, their environmental friendliness, sustainability, renewability, easy accessibility, and cost-effectiveness should be considered. In this study, GO incorporated semi-interpenetrating network (semi-IPN) nanocomposite hydrogels (CS/AAm/IA/GO) were obtained by free radical copolymerization of acrylamide (AAm) and itaconic acid (IA) in the presence of chitosan (CS) as an environmentally friendly bio-adsorbent. GO significantly improved the thermal stability, compressive strength, and percentage swelling of the hydrogel. The selective adsorption studies demonstrated that methylene blue (MB) was the most efficiently removed dye from both individual and mixed dye systems with 99.8 % removal efficiency. The adsorption capacity was found to be 247.47 mg g using 0.025 g hydrogel adsorbent containing 0.5 wt% of GO and an initial MB concentration of 5 mg L at pH 8 over 90 min at room temperature. The kinetic and isotherm studies revealed that the adsorption process followed the pseudo-second-order kinetic model and Langmuir adsorption isotherm. Thermodynamic studies suggested the spontaneous and endothermic nature of MB adsorption. Also, the MB removal efficiency above 96 % was obtained after 7 consecutive adsorption-desorption cycles while maintaining the structural stability of the bio-adsorbent.
近年来，聚合生物吸附剂在去除水中各种污染物方面表现出了高效的去除效率、优异的吸附容量和选择性。在设计这些吸附剂时，应考虑其环境友好性、可持续性、可再生性、易于获取性和成本效益。在这项研究中，通过丙烯酰胺（AAm）和衣康酸（IA）的自由基共聚，在壳聚糖（CS）存在下得到了 GO 掺入的半互穿网络（semi-IPN）纳米复合水凝胶（CS/AAm/IA/GO），作为一种环境友好型生物吸附剂。GO 显著提高了水凝胶的热稳定性、压缩强度和溶胀率。选择性吸附研究表明，亚甲基蓝（MB）是从单一和混合染料体系中去除效率最高的染料，去除率达到 99.8%。在室温下，使用含有 0.5wt%GO 的 0.025g 水凝胶吸附剂，在初始 MB 浓度为 5mg/L、pH 值为 8 的条件下，吸附 90min 后，吸附容量为 247.47mg/g。动力学和等温线研究表明，吸附过程遵循准二级动力学模型和 Langmuir 吸附等温线。热力学研究表明，MB 的吸附是自发和吸热的。此外，在 7 次连续的吸附-解吸循环后，MB 的去除效率仍保持在 96%以上，同时保持了生物吸附剂的结构稳定性。
