College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.
National Engineering Technique Research Center for Biotechnology, Nanjing, China.
Sci Rep. 2020 Jun 15;10(1):9623. doi: 10.1038/s41598-020-66592-8.
A series of methylamine-modified hyper-cross-linked resins were fabricated from chloromethylated polystrene-co-divinylbenzene by two continuous reactions (Friedel-Crafts alkylation and amination). The BET surface area and pore volume of the as-prepared resins took a positive correlation to the reaction time and temperature during alkylation reaction while lessened during amination process. When running batch adsorption experiments for adsorption of citric acid, the methylamine-modified resin named HM-65-2 showed higher adsorption capacity of 136.3 mg/g and selectivity of 6.98 (citric/glucose) than the precursor resins. The pseudo-second-order rate model fitted better than the pseudo-first-order model, implying the adsorption sites distributed on the resins surface tended to be heterogeneous. Subsequently, the interactions between citric acid and the resin were investigated by means of molecular simulation. Simulation result showed the addition of nitrogen-containing groups significantly enhanced the adsorption performance of citric acid. Lastly, the dynamic column experiments were performed to obtain the suitable operating conditions for the citric acid adsorption.
一系列甲胺改性超交联树脂是由氯甲基化聚苯乙烯-二乙烯基苯通过两个连续反应（傅克烷基化和胺化）制备的。所制备的树脂的 BET 表面积和孔体积与烷基化反应过程中的反应时间和温度呈正相关，而在胺化过程中则降低。在进行柠檬酸的批式吸附实验时，名为 HM-65-2 的甲胺改性树脂表现出比前体树脂更高的吸附容量 136.3mg/g 和选择性 6.98（柠檬酸/葡萄糖）。准二级速率模型比准一级速率模型拟合得更好，这表明吸附位分布在树脂表面上趋于不均匀。随后，通过分子模拟研究了柠檬酸与树脂之间的相互作用。模拟结果表明，含氮基团的加入显著提高了柠檬酸的吸附性能。最后，进行了动态柱实验以获得柠檬酸吸附的合适操作条件。
