聚氧乙烯基碳捕集膜的多级结构调控与传递机制强化
发布时间：2019-03-28 07:05
【摘要】：高效碳捕集技术是实现温室气体减排和能源气体净化的重要途径。膜技术以其能耗低、操作弹性高等优势成为最具发展前景的CO_2捕集技术之一。开发高渗透性、高选择性、高稳定性的CO_2分离膜材料是膜技术成功应用的关键。为此,需深入揭示CO_2在膜内的传递机制,设计特异性、高效传递的膜结构。本研究以PEO基高分子作为多功能改性剂,采用简便、温和的制膜方法制备了一系列具适宜亲疏性和自由体积特性的CO_2分离膜,提出针对膜主体、界面、表面、通道结构调控实现膜溶解机制与扩散机制协同强化的策略,实现了CO_2/N_2、CO_2/CH_4的高效分离,以期为高性能CO_2分离膜的规模化制备提供理论基础与技术支持。研究结果如下:膜主体结构调控与传递机制强化:通过在橡胶态高分子Pebax中引入PEG/CNT或含PEG的硅烷凝胶网络,制备了有机-无机杂化膜,通过PEG对膜主体亲和性的调控强化了膜的溶解机制,无机粒子的引入干扰了膜主体结晶行为,强化了膜的扩散机制。同时含有PEGDMA和CNT杂化膜的CO_2渗透系数达743 Barrer,CO_2/N_2的选择性达108,突破了2008年的Robeson上界。硅凝胶网络的引入显著提升了膜的机械性能。膜界面结构调控与传递机制强化:提出了以有机PEG微球作为填充剂,引入玻璃态PI中,改善膜界面形态、强化膜界面传递特性的膜设计制备方法。高分子-填充剂良好的界面形态和亲CO_2特性使膜溶解、扩散机制同时强化,与纯PI膜相比,PI PEGSS(20)膜的CO_2渗透速率提高了35%,CO_2/N_2选择性提高了104%。膜表面结构调控与传递机制强化:提出了以表面偏析技术构建亲CO_2非对称膜表面的方法。以玻璃态PES为高分子主体,含PEO的嵌段共聚物F68作为改性剂,膜表面富集的PEO增强了膜表面CO_2亲和性,膜主体自由体积特性由PPO的引入实现强化,从而实现了溶解-扩散机制协同强化。含20 wt%F68的非对称膜相比纯PES膜CO_2渗透通量提高了210%,CO_2/N_2选择性提高了105%。膜通道结构调控与传递机制强化:使用不同分子量PEGDA作为交联剂,综合PEGDA的CO_2亲和性和交联特性,制备了GO复合膜。通过膜通道CO_2亲和性和膜通道尺寸协同调控,实现了溶解-扩散机制协同强化。GO-PEGDA500相比与纯GO膜,CO_2渗透通量提高了284%,CO_2/CH_4选择性提高了294%。
[Abstract]:High-efficiency carbon capture technology is an important way to realize greenhouse gas emission reduction and energy gas purification. The membrane technology is one of the most promising CO _ 2 trapping technologies because of its low energy consumption and high operating elasticity. The development of CO _ 2 separation membrane material with high permeability, high selectivity and high stability is the key to the successful application of membrane technology. To this end, the transfer mechanism of CO _ 2 in the membrane needs to be further revealed, and the membrane structure with specific and high efficiency is designed. In this study, a series of CO _ 2 separation membranes with suitable hydrophobicity and free-volume characteristics were prepared by using PEO-based polymer as a multifunctional modifier. The effective separation of CO _ 2/ N _ 2 and CO _ 2/ CH _ 4 is realized by the strategy of the channel structure regulation and control to realize the synergistic enhancement of the membrane dissolution mechanism and the diffusion mechanism, so as to provide the theoretical basis and technical support for the large-scale preparation of the high-performance CO _ 2 separation membrane. The results of the study are as follows: the structure regulation and transmission mechanism of the membrane main body is strengthened: the organic-inorganic hybrid membrane is prepared by introducing the PEG/ CNT or the PEG-containing silane gel network in the rubbery polymer Pebax, and the dissolution mechanism of the membrane is strengthened through the regulation and control of the affinity of the membrane main body through the PEG, The introduction of inorganic particles interfere with the crystallization behavior of the film main body and strengthen the diffusion mechanism of the film. At the same time, the permeability coefficient of CO _ 2, which contains the PEGDMA and the CNT hybrid membrane, is as high as 743 Barrer, and the selectivity of CO _ 2/ N _ 2 reaches 108, which breaks through the upper bound of the Robeson in 2008. The introduction of a silicon gel network significantly improves the mechanical properties of the film. The control and transmission mechanism of the membrane interface is enhanced by introducing the organic PEG microsphere as a filler, introducing the glass state PI, improving the interface morphology of the membrane, and enhancing the membrane interface transfer characteristic. 楂樺垎瀛，
本文编号：2448646
[Abstract]:High-efficiency carbon capture technology is an important way to realize greenhouse gas emission reduction and energy gas purification. The membrane technology is one of the most promising CO _ 2 trapping technologies because of its low energy consumption and high operating elasticity. The development of CO _ 2 separation membrane material with high permeability, high selectivity and high stability is the key to the successful application of membrane technology. To this end, the transfer mechanism of CO _ 2 in the membrane needs to be further revealed, and the membrane structure with specific and high efficiency is designed. In this study, a series of CO _ 2 separation membranes with suitable hydrophobicity and free-volume characteristics were prepared by using PEO-based polymer as a multifunctional modifier. The effective separation of CO _ 2/ N _ 2 and CO _ 2/ CH _ 4 is realized by the strategy of the channel structure regulation and control to realize the synergistic enhancement of the membrane dissolution mechanism and the diffusion mechanism, so as to provide the theoretical basis and technical support for the large-scale preparation of the high-performance CO _ 2 separation membrane. The results of the study are as follows: the structure regulation and transmission mechanism of the membrane main body is strengthened: the organic-inorganic hybrid membrane is prepared by introducing the PEG/ CNT or the PEG-containing silane gel network in the rubbery polymer Pebax, and the dissolution mechanism of the membrane is strengthened through the regulation and control of the affinity of the membrane main body through the PEG, The introduction of inorganic particles interfere with the crystallization behavior of the film main body and strengthen the diffusion mechanism of the film. At the same time, the permeability coefficient of CO _ 2, which contains the PEGDMA and the CNT hybrid membrane, is as high as 743 Barrer, and the selectivity of CO _ 2/ N _ 2 reaches 108, which breaks through the upper bound of the Robeson in 2008. The introduction of a silicon gel network significantly improves the mechanical properties of the film. The control and transmission mechanism of the membrane interface is enhanced by introducing the organic PEG microsphere as a filler, introducing the glass state PI, improving the interface morphology of the membrane, and enhancing the membrane interface transfer characteristic. 楂樺垎瀛，
本文编号：2448646
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