Zhou Yan, Zhang Yi, Wang Xiong, Diao Jianglin, Zhang Yunjv
Mianyang Teachers' College, Mianyang 621000, Sichuan, China.
College of Plant Protection, Southwest University, Beibei 400715, Chongqing, China.
Int J Biol Macromol. 2022 Dec 1;222(Pt B):3034-3044. doi: 10.1016/j.ijbiomac.2022.10.078. Epub 2022 Oct 13.
Lignin, as a biodegradable byproduct of industry, has become popular in developing low-cost and high-performance heavy metal adsorbents. Herein, a high-efficiency novel adsorbent for mercury ion, amino-functionalization alkali lignin (AAL) was facile synthesized by one-step approach under very mild conditions. The as-prepared AAL was characterized by FT-IR, BET, XPS and SEM. The adsorption properties of AAL for Hg were elucidated in batch system. The results showed that AAL exhibited exceptionally high adsorption capacity for Hg at pH of 4- 6, the maximum adsorption capacity can reach 553.9 mg g. The remove efficiency could above 99% when dealing with 300 mg L of Hg solution at 30 °C using 1 g L adsorbent. The adsorption was a spontaneous endothermic process. Pseudo-second-order kinetic and Langmuir isotherm model fitted well with the sorption data, which proposed the adsorption was a monolayer chemical adsorption process. The mechanism analysis demonstrated that nitrogen-containing functional groups of AAL were mainly contributed to the adsorption of Hg. Moreover, the adsorption capacity of the regenerated AAL could still be maintained at 91% by the fifth cycle. These findings demonstrated that AAL can provide an effective way to enhancing removal of Hg from aqueous solutions.
木质素作为一种可生物降解的工业副产品，在开发低成本、高性能的重金属吸附剂方面已受到广泛关注。在此，通过一步法在非常温和的条件下简便地合成了一种高效的新型汞离子吸附剂——氨基官能化碱木质素（AAL）。采用傅里叶变换红外光谱（FT-IR）、比表面积分析仪（BET）、X射线光电子能谱（XPS）和扫描电子显微镜（SEM）对所制备的AAL进行了表征。在间歇系统中研究了AAL对汞的吸附性能。结果表明，AAL在pH值为4 - 6时对汞表现出极高的吸附容量，最大吸附容量可达553.9 mg/g。当使用1 g/L的吸附剂在30℃处理300 mg/L的汞溶液时，去除效率可超过99%。吸附是一个自发的吸热过程。准二级动力学和朗缪尔等温线模型与吸附数据拟合良好，表明吸附是一个单层化学吸附过程。机理分析表明，AAL含氮官能团对汞的吸附起主要作用。此外，再生后的AAL在第五次循环时吸附容量仍可保持在91%。这些研究结果表明，AAL为提高水溶液中汞的去除率提供了一种有效途径。
