改性木质素气凝胶的制备及其吸附性能研究

Preparation and adsorption property of modified lignin aerogel

以乙酸木质素(AL)和马来酸酐(MA)为原料通过酯化反应得到改性木质素(ML),然后与丙烯酸自由基聚合制备木质素气凝胶(MLA)。表征并分析了ML的化学结构和MLA的内部结构,探讨了吸附时间、溶液pH对Cu^(2+)吸附性能的影响。结果表明:ML的加入不但增加了MLA表面的吸附官能团,还改善了气凝胶的内部孔隙结构,提高了对Cu^(2+)的吸附性能,在硫酸铜的初始浓度为50mg/L,平衡吸附容量达到135.65mg/g,去除率达到91.16%。根据等温吸附曲线和吸附动力学研究显示,Langmiur吸附模型能更好地描述吸附过程,吸附过程遵循准二级动力学方程。

Using acetic acid lignin(AL) and maleic anhydride(MA) as raw materials,modified lignin(ML) was obtained through esterification reaction,the lignin aerogel(MLA) was prepared by free-radical polymerization with acrylic acid.The chemical structure of ML and the internal structure of MLA were characterized and analyzed,and discussed the effects of adsorption time and solution pH on the adsorption performance for copper.The results shown that the addition of ML not only increased the adsorption functional groups on the surface of the MLA,but also improved the internal pore structure of the aerogel,and improved the adsorption performance for copper.The initial concentration of copper sulfate was 50 mg/L,and the equilibrium adsorption capacity reached 135.65 mg/g,the removal rate was 91.16%.The results of adsorption isotherms and kinetics shown that the Langmuir isotherm adsorption model can better reflect the adsorption process,and the adsorption process followed the pseudo-second order kinetic equation.