Department of Paper Science & Engineering, College of Forest and Environmental Sciences, Kangwon National University, Chuncheon, 24341, Republic of Korea.
Department of Paper Science & Engineering, College of Forest and Environmental Sciences, Kangwon National University, Chuncheon, 24341, Republic of Korea.
Chemosphere. 2022 May;295:133815. doi: 10.1016/j.chemosphere.2022.133815. Epub 2022 Jan 29.
Research on low-cost bio-adsorbents for the removal of harmful substances from effluents has recently attracted significant attention. In this study, three types of amino-silane-modified lignins (ASLs) with primary, secondary, and tertiary amine groups were prepared, and their adsorption behavior toward cationic and anionic dyes was investigated. Chemical structural analyses indicated that the three amino-silane reagents resulted in different molecular self-assembly structures on the lignin surface. The ASLs exhibited enhanced thermal stabilities and increased surface areas with different surface charges in different pH ranges. Owing to the high density of primary, secondary, and tertiary amine groups, the ASLs exhibited excellent adsorption capacities for cationic and anionic dyes. Additionally, they selectively adsorb anionic and cationic dyes according to the pH conditions. The ASL with primary amine had the highest adsorption capacity for Methylene blue and Congo red, reaching 187.27 and 293.26 mg·g, respectively, followed by ASLs with the secondary amine and tertiary amine. All adsorption processes followed the Langmuir and Temkin isotherms and had pseudo-second-order kinetics. The hypothesized adsorption mechanism mainly involves electrostatic interaction, NH-π interaction, hydrogen bonding interaction and π-π interaction.
近年来，人们对从废水中去除有害物质的低成本生物吸附剂的研究引起了广泛关注。在本研究中，制备了三种带有伯、仲、叔胺基团的氨基硅烷修饰木质素（ASLs），并研究了它们对阳离子和阴离子染料的吸附行为。化学结构分析表明，三种氨基硅烷试剂在木质素表面导致了不同的分子自组装结构。ASLs 表现出增强的热稳定性和不同表面电荷的表面积增加，在不同的 pH 范围内。由于伯、仲、叔胺基团的高密度，ASLs 对阳离子和阴离子染料表现出优异的吸附能力。此外，它们根据 pH 条件选择性地吸附阴离子和阳离子染料。带有伯胺的 ASL 对亚甲蓝和刚果红的吸附容量最高，分别达到 187.27 和 293.26 mg·g-1，其次是带有仲胺和叔胺的 ASL。所有吸附过程均遵循 Langmuir 和 Temkin 等温线和拟二级动力学。假设的吸附机制主要涉及静电相互作用、NH-π 相互作用、氢键相互作用和 π-π 相互作用。
