Amines are incorporated into various membranes to improve their CO 2 separation performance. With amine-containing polymeric membranes, gas transport properties are often enhanced under humidity, where CO 2 migrates through the membranes in the form of bicarbonate ions. Piperazine (Pz) and its derivatives are known to catalyze the conversion of CO 2 to bicarbonate ions and have been used in liquid amine scrubbing technology. Piperazines were immobilized in poly(vinyl alcohol) (PVA), and the resulting polymeric membranes showed high CO 2 separation performance over H 2 and CH 4 . The gas transport properties were dependent on the chemical structure of the amines. In particular, 3-(1-piperazinyl)-1,2-propanediol (PzPD)-containing polymeric membranes gave excellent CO 2 separation performance, and the CO 2 permeability and CO 2 selectivity over CH 4 were 1060 Barrer and 370, respectively, at 50 °C and 90% relative humidity with a transmembrane CO 2 pressure of 11 kPa. The interaction between PzPD and CO 2 was quantitatively studied by inverse-gate decoupling 13 C NMR spectroscopy. CO 2 interacted with the secondary amino group on the Pz ring to form a carbamate, which was readily hydrolyzed to produce bicarbonate ions. The hydroxyl group on the C2 carbon of PzPD facilitated the interaction between CO 2 and the amine through hydrogen bonding, resulting in enhanced diffusivity of CO 2 in the membranes. Piperazine and its derivatives were incorporated into a thin film of poly(vinyl alcohol), and the CO 2 separation performance of the resulting amin-containing membranes was investigated. The gas transport properties were dependent on the chemical structure of the amines. In particular, 3-(1-piperazinyl)-1,2-propanediol (PzPD)-containing polymeric membranes gave excellent CO 2 separation properties over H 2 and CH 4 under humidity. CO 2 interacted with the secondary amino group on the Pz ring to form a carbamate, which was readily hydrolyzed to produce bicarbonate ions. CO 2 migrates through the membrane in the form of bicarbonate ions.

中文翻译：

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用于 CO2 捕获的哌嗪固定聚合物膜：CO2 优先渗透机制

胺被掺入到各种膜中以提高它们的CO 2 分离性能。使用含胺聚合物膜，气体传输特性通常在湿度下增强，其中 CO 2 以碳酸氢根离子的形式迁移通过膜。已知哌嗪 (Pz) 及其衍生物可催化 CO 2 转化为碳酸氢根离子，并已用于液体胺洗涤技术。哌嗪固定在聚乙烯醇 (PVA) 中，所得聚合物膜表现出优于 H 2 和 CH 4 的高 CO 2 分离性能。气体传输特性取决于胺的化学结构。特别是含有 3-(1-哌嗪基)-1,2-丙二醇 (PzPD) 的聚合物膜具有优异的 CO 2 分离性能，并且CO 2 渗透率和CO 2 对CH 4 的选择性分别为1060 Barrer 和370，在50 °C 和90% 相对湿度下，跨膜CO 2 压力为11 kPa。PzPD 和 CO 2 之间的相互作用通过反向门去耦 13 C NMR 光谱进行定量研究。CO 2 与Pz 环上的仲氨基相互作用形成氨基甲酸酯，该氨基甲酸酯易于水解生成碳酸氢根离子。PzPD 的 C2 碳上的羟基通过氢键促进 CO 2 与胺之间的相互作用，从而增强了 CO 2 在膜中的扩散性。将哌嗪及其衍生物掺入聚乙烯醇薄膜中，研究了所得含胺膜的 CO 2 分离性能。气体传输特性取决于胺的化学结构。特别是，含 3-(1-哌嗪基)-1,2-丙二醇 (PzPD) 的聚合物膜在潮湿条件下比 H 2 和 CH 4 具有优异的 CO 2 分离性能。CO 2 与Pz 环上的仲氨基相互作用形成氨基甲酸酯，该氨基甲酸酯易于水解生成碳酸氢根离子。CO 2 以碳酸氢根离子的形式迁移通过膜。