聚离子液体改性废报纸基纤维素气凝胶及其染料吸附性能研究

Study on Polymeric Ionic Liquid Modified Waste Newspaper-based Cellulosic Aerogel and Its Dye Adsorption Performance

采用超声脱墨技术纯化废报纸(WNP),将得到的脱墨纤维素纤维在碱溶剂体系中溶解并交联再生制备纤维素气凝胶(WNCA),最后通过化学接枝法制备了聚(1-乙烯基-3-丁基咪唑溴盐)聚合物刷修饰的纤维素气凝胶吸附剂(WNCA-g-PBVIMBr);研究了WNCA-g-PBVIMBr的化学结构与物理形貌,探索了其对染料酸性橙Ⅱ (AO Ⅱ)的吸附性能与吸附机理。结果表明,WNCA表面均匀接枝了平均分子质量为3780 g/mol的PBVIMBr聚合物刷,其对AO Ⅱ的最大吸附容量为351 mg/g,吸附过程符合准二级动力学模型和Langmuir等温吸附模型,且化学吸附起主导作用。

In this study,the waste newspaper(WNP)was purified via ultrasonic deinking to obtain the deinked cellulose fiber which was then dissolved in alkaline solvent system and cross-linked to prepare regenerated cellulose aerogel(WNCA).The poly(1-vinyl-3-butylimidazole bromide)brush modified cellulosic aerogel adsorbent(WNCA-g-PBVIMBr)was obtained by chemical grafting.The chemical structure and physical morphology of WNCA-g-PBVIMBr were studied,and the adsorption performance and mechanism towards acid orange Ⅱ(AO Ⅱ)were explored as well.The results showed that the PBVIMBr polymer brush with an average molecular weight of 3780 g/mol was uniformly grafted on the surface of WNCA,of which the maximum adsorption capacity towards AO Ⅱ could reach 351 mg/g.The adsorption process conformed to the pseudo-second-order kinetic model and Langmuir adsorption isotherm model,indicating chemical adsorption played a key role in the adsorption process.