氧化石墨烯-埃洛石纳米管/壳聚糖-聚乙烯胺混合基质膜促进传递二氧化碳机理研究

Fixed-site-carrier membrane is a kind of promising membrane for gas separation; the active carriers which could react reversibly with CO2 are fixed within the membrane, which could prevent the loss of the carriers. Therefore, it is very important for CO2 pollution reduction and capture. In this project, halloysite nanotube (HNT) with large number of hydroxyl groups and graphene oxide (GO)with many groups containing oxide are selected and the mixed matrix membrane based on HNT and GO will be prepared and used for the study of CO2 facilitated transport. Its specific contents include: HNT will be modified by surface-initiated atom transfer radical polymerization (SI-ATRP) grafted 4-vinyl pyridine. GO will be grafted by hyperbranched polyethyleneimine (HPEI). GO-HNT nanocomposites with sandwich structure will be prepared. And then, the above three inorganic nanomaterials will be added into the polymer solution of chitosan-polyvinyl amine blend to prepare mixed matrix membrane based on HNT and GO. In order to determine the optimal condition, the effects of inorganic nanomaterials content, the composition of the casting solution and operating condition on the permeability and selectivity will be investigated. And in order to determine the influence factors and enhancement approaches, the facilitated transport mechanism and synergistic effects of CO2 in the membrane will be studied and mathematical model and optimization design will also be proposed. It will supply theoretical base for the fabrication of the mixed matrix membrane with excellent performance.

固定载体膜是将与CO2发生可逆反应的活性载体固定在膜内，阻止了载体流失，是一类极具发展前途的气体分离膜，对于CO2减排与捕集具有重要意义。本项目利用埃洛石纳米管带有大量羟基及氧化石墨烯表面带有大量含氧官能团的特点，制备基于埃洛石纳米管和氧化石墨烯的混合基质膜，用于CO2促进传递研究。主要内容包括：采用表面引发原子转移自由基聚合在HNT表面接枝4-乙烯基吡啶；将超支化聚乙烯亚胺接枝到GO表面；制备具有三明治结构的GO-HNT纳米复合材料。然后将以上三种无机纳米材料引入到壳聚糖-聚乙烯胺混合液中，制备基于HNT和GO的混合基质膜；考察无机纳米材料含量、铸膜液组成及操作条件对膜渗透性能和选择性的影响，确定最佳配方和最优操作条件；探讨CO2在膜内的促进传递机理和协同效应，提出数学模型及最优化设计，确定影响因素和强化途径，为高效混合基质膜的构建提供理论依据。

本项目利用埃洛石纳米管带有大量羟基及氧化石墨烯表面带有大量含氧官能团的特点，制备了基于埃洛石纳米管和氧化石墨烯的混合基质膜，用于二氧化碳促进传递研究。考察了无机纳米材料含量、铸膜液组成及操作条件对膜渗透性能和选择性的影响，确定最佳配方和最优操作条件；探讨二氧化碳在膜内的促进传递机理和协同效应，提出最优化设计，确定影响因素和强化途径，为高效混合基质膜的构建提供理论依据，为碳捕集提供技术支持。同时，本研究将埃洛石纳米管和氧化石墨烯的特殊性能与膜分离的优势相结合，拓展了它们在气体分离领域中的应用。目前，本项目研究结果已在J. Mater. Chem. A, J. Membr. Sci., ACS Appl. Mater. Interfaces, Nanoscale, Ind. Eng. Chem. Res.,等期刊发表论文10篇，并得到国内外同行关注。