分别用NaOH/脲/H2O和NaOH/硫脲/H2O、离子液体1-丁基-3-甲基咪唑氯盐(BMIMCl)和1-烯丙基-3-甲基咪唑氯盐(AMIMCl)四种溶解体系溶解脱脂棉纤维素,制得不同的纤维素基气凝胶,对产品进行了表征,考察了不同气凝胶对氯酸根离子(ClO3?)吸附性能的差异. 结果表明,纤维素基气凝胶的晶型结构均由I型转为Ⅱ型结构,BMIMCl溶解体系所制气凝胶结晶度较其它溶解体系低,热稳定性也较差,但其比表面积和总孔容较高,平均孔径较小,对水溶液中微量ClO3-?的吸附性能较好.
In order to study the properties of cellulose-based aerogels obtained from different dissolution systems, cotton cellulose was dissolved in four kinds of dissolving system including NaOH/urea/H2O, NaOH/thiourea/H2O, ionic liquids 1-butyl-3-methylimidazolium chloride (BMIMCl) and 1-allyl-3-methylimidazolium chloride salt (AMIMCl). Additionally, the obtained cellulose-based aerogels were characterized, and the adsorption performance to chlorate ions (ClO3?) were studied. The results showed that the crystal structures of cellulose-based aerogels transforms from type I into II. The aerogels obtained from BMIMCl solvent system gives lower crystallinity a thermal stability than those from the other solvent systems, whereas it possesses higher specific surface area, total pore volume and smaller average pore size, and higher adsorption performance for trace amount of ClO3? in aqueous solution.
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