Bendaoudi Amine Ahmed, Boudouaia Nacer, Jellali Salah, Benhafsa Fouad Mekhalef, Bengharez Zohra, Papamichael Iliana, Jeguirim Mejdi
Laboratory of Advanced Materials and Physicochemistry for Environment and Health, Djillali Liabes University, Sidi Bel Abbes, Algeria.
Center for Environmental Studies and Research, Sultan Qaboos University, Muscat, Oman.
Waste Manag Res. 2024 Jun;42(6):495-507. doi: 10.1177/0734242X231188667. Epub 2023 Jul 31.
Hydrogels based on natural polysaccharides have received special attention in the last decade due to their interesting features, such as availability, biocompatibility, biodegradability and safety. Such characteristics may make them sustainable and eco-friendly materials for water and wastewater treatment, meeting the concept of circular economy. In this study, a novel double-cross-linked alginate-based hydrogel has been successfully synthesized using epichlorhydrin and sodium trimetaphosphate (STMP) as cross-linker agents and then used for the removal of methylene blue (MB) dye under different operating conditions. The obtained hydrogel was deeply characterized by using various analytical techniques, namely Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and differential scanning calorimetry. Experimental results showed that the synthesized double cross-linked hydrogel with relatively high STMP concentration (0.26 M) has promising structural and textural properties. This material exhibited excellent removal ability towards MB with a maximum adsorption capacity of about 992 mg/g for an initial pH of 10. The kinetic and isotherm modeling study revealed that the pseudo-second-order and Freundlich models fitted well the measured adsorption experimental data. The MB adsorption process onto the synthesized hydrogel is exothermic, feasible and spontaneous. It mainly includes electrostatic interaction and hydrogen bonds. These findings suggest that double-cross-linked alginate-based hydrogel can be considered as an attractive and potential adsorbent for an effective cationic dye removal from aqueous environments. The use of such a green adsorbent for the treatment of organic-pollutants-rich industrial wastewaters promotes sustainability and circular economy concepts.
在过去十年中，基于天然多糖的水凝胶因其具有诸如可得性、生物相容性、生物降解性和安全性等有趣特性而受到特别关注。这些特性可能使它们成为用于水和废水处理的可持续且环保的材料，符合循环经济的概念。在本研究中，已成功合成了一种新型的基于藻酸盐的双交联水凝胶，使用环氧氯丙烷和三聚磷酸钠（STMP）作为交联剂，然后用于在不同操作条件下去除亚甲基蓝（MB）染料。通过使用各种分析技术，即傅里叶变换红外光谱、X射线衍射、扫描电子显微镜和差示扫描量热法，对所得水凝胶进行了深入表征。实验结果表明，具有相对较高STMP浓度（0.26 M）的合成双交联水凝胶具有良好的结构和质地性能。该材料对MB表现出优异的去除能力，在初始pH为10时最大吸附容量约为992 mg/g。动力学和等温线建模研究表明，伪二级和弗伦德利希模型与测得的吸附实验数据拟合良好。MB在合成水凝胶上的吸附过程是放热的、可行的且自发的。它主要包括静电相互作用和氢键。这些发现表明，基于藻酸盐的双交联水凝胶可被视为一种有吸引力的潜在吸附剂，用于从水环境中有效去除阳离子染料。使用这种绿色吸附剂处理富含有机污染物的工业废水促进了可持续性和循环经济概念。
