College of Energy and Environment, Inner Mongolia University of Science and Technology, Baotou 014010, PR China.
College of Material Science and Engineering, Inner Mongolia University of Science and Technology, Baotou 014010, PR China.
Int J Biol Macromol. 2024 Nov;281(Pt 1):136289. doi: 10.1016/j.ijbiomac.2024.136289. Epub 2024 Oct 4.
In the background of severe water pollution, adsorption is a charming technique for heavy metal remediation. In this work, NiFeO decorated chitosan-graphene oxide (NFCG) was prepared by simple hydrothermal method for Co(II) remediation application. Adsorption mechanism was elaborately elucidated based on multiple evidences extracted from adsorption fitting (isotherms, thermodynamics and kinetics), spectroscopic test (XPS, UV-Vis absorption, fluorescent emission and Raman spectra) and the hard-soft acid-base (HSAB) theory inspection. Result shows, for Co(II) with initial concentration 200 mg·L, NFCG with dosage 500 mg·L reaches adsorption equilibrium in 24 min, rendering removal percentage and adsorption amount 96.87 % and 387.48 mg·g, respectively. Owing to the efficient recovery enabled by paramagnetism, NFCG keeps adsorption amount 311.01 mg·g for Co(II) after six consecutive cycles. Moreover, NFCG exhibits selectivity towards Co(II) under the coexistence of common interfering substances. Adsorption fitting suggests chemical adsorption based on heterogeneous affinity. Spectroscopic analysis discloses, CO, CO, -C(=O)NH-, OH and aromatic part contribute to Co(II) adsorption via electron donation, forming CoO bond. This atomic scale adsorption mechanism was substantiated by HSAB theory calculation. In brief, this work provides basic knowledge and technical support for fabricating high efficiency magnetic bio adsorbent.
在严重水污染的背景下，吸附是一种用于重金属修复的有吸引力的技术。在这项工作中，通过简单的水热法制备了 NiFeO 修饰的壳聚糖-氧化石墨烯（NFCG），用于 Co(II)修复应用。通过吸附拟合（等温线、热力学和动力学）、光谱测试（XPS、UV-Vis 吸收、荧光发射和拉曼光谱）和软硬酸碱（HSAB）理论检验，从多个证据中详细阐明了吸附机制。结果表明，对于初始浓度为 200 mg·L 的 Co(II)，用量为 500 mg·L 的 NFCG 在 24 min 内达到吸附平衡，去除率和吸附量分别为 96.87%和 387.48 mg·g。由于顺磁性实现的高效回收，NFCG 在六个连续循环后对 Co(II)的吸附量保持在 311.01 mg·g。此外，NFCG 在常见干扰物质共存下对 Co(II)表现出选择性。吸附拟合表明，基于非均相亲和力的化学吸附。光谱分析表明，CO、CO、-C(=O)NH-、OH 和芳基部分通过电子供体与 Co(II)吸附，形成 CoO 键。HSAB 理论计算证实了这种原子尺度的吸附机制。总之，这项工作为制备高效磁性生物吸附剂提供了基础知识和技术支持。
