由于木质素是一类三维复杂结构的疏水性分子,在制备吸附剂时反应活性不佳,需对其改性后使用,使用氯化胆碱/尿素低共熔离子液体对木质素改性,与N-异丙基丙烯酰胺聚合制备了改性木质素基吸附剂。红外谱图和扫描电镜图表明,改性后木质素三维空间网络结构的得到充分利用,反应活性增大。通过合成条件的优化,获得N-异丙基丙烯酰胺:木质素:N,N'-亚甲基双丙烯酰胺原料配比为60∶6∶1。对影响吸附性能的因素分析表明,平衡吸附量在室温p H值为9时,最高达122 mg·g-1;且随温度升高近似呈单指数衰减过程。吸附动力学曲线较符合准二级动力学反应模型,具有一定的缓控释化学品应用潜力。
A modified lignin - based adsorbent was prepared by N - isopropylacrylam and lignin, which was mod- ified by deep eutectic solvent (DES) as choline chloride/urea. The FT- IR spectrum and SEM photos showed that the three - dimensional network structure of modified lignin had been fully utilized ,. and the reaction activity of lignin had been increased. The synthesis conditions was optimized to obtain the raw materials ratio, with N - isopropylacrylam : lignin :N: N' -methylene bisacrylamide as 60: 6: 1. The analysis of the factors affecting the adsorption properties showed that the equilibrium adsorption quantity was 122 mg · g-1 in the condition of indoor temperature and pH = 9, and the adsorption approximated as a single exponential decay with the increase of temperature. The adsorption kinetics curve accorded with the quasi - second order kinetic model, which has the poter, tial to be used as a sustained -release polymer material.