Wu Meiyan, Zhang Yidong, Feng Xiaoyan, Yan Fei, Li Qian, Cui Qiu, Li Bin
CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, P.R. China.
Laboratory of Natural Materials Technology, Åbo Akademi University, 20500 Turku, Finland.
iScience. 2023 Aug 29;26(10):107783. doi: 10.1016/j.isci.2023.107783. eCollection 2023 Oct 20.
Congo red is hard to remove from dye wastewater due to its structure stability and high chemical oxygen demand. In this study, cationic cellulose nanofibrils (CCNF) prepared from herb residues was physically crosslinked with sodium alginate (SA) in the presence of calcium ions, and the obtained CCNF/SA beads were used to adsorb Congo red. Results showed that CCNF/SA beads with porous internal structure were beneficial to adsorption. The maximum adsorption capacity of Congo red could reach to 518.4 mg/g, which was superior to most cellulose-based adsorption materials. Furthermore, the equilibrium adsorption isotherms and XPS analysis indicated the adsorption for Congo red was a physical process, and hydrogen bond and electrostatic adsorption were proposed as dominant adsorption mechanism. In addition, the Congo red removal efficiency of the beads was still higher than 70% after three cycles. Therefore, this high efficiency and green beads have great potential as adsorbents for anionic dyes removal.
由于刚果红的结构稳定性和高化学需氧量，它很难从染料废水中去除。在本研究中，由草本植物残渣制备的阳离子纤维素纳米纤维（CCNF）在钙离子存在下与海藻酸钠（SA）进行物理交联，所得的CCNF/SA珠粒用于吸附刚果红。结果表明，具有多孔内部结构的CCNF/SA珠粒有利于吸附。刚果红的最大吸附容量可达518.4 mg/g，优于大多数纤维素基吸附材料。此外，平衡吸附等温线和XPS分析表明，对刚果红的吸附是一个物理过程，氢键和静电吸附被认为是主要的吸附机制。此外，经过三个循环后，珠粒对刚果红的去除效率仍高于70%。因此，这种高效且绿色的珠粒作为去除阴离子染料的吸附剂具有巨大潜力。
