The development of efficient membranes for ethylene/ethane (C2H4/C2H6) separation is highly important. Here, we report the development of a series of new mixed matrix membranes (ZnAtzPO4/6FDA-DAM MMMs) based on a microporous material with phosphate anion pillar ZnAtzPO4 (Atz = 3-amino-1, 2, 4-triazole) and 6FDA-DAM polymer matrix. Compared with the pure 6FDA-DAM membranes, the C2H4 permeability and the C2H4/C2H6 selectivity of 10 wt % ZnAtzPO4/6FDA-DAM MMMs were simultaneously increased by 46 and 6%, breaking the trade-off between permeability and selectivity. Interestingly, the separation performance of ZnAtzPO4/6FDA-DAM MMMs at 10 wt % for the equimolar C2H4/C2H6 gas mixture was 105.0 Barrer and 3.90, which surpassed the 2013 upper bound of C2H4/C2H6. For ZnAtzPO4/6FDA-DAM MMMs with 10 wt % filler loading, both the solubility selectivity and the diffusion selectivity continued to rise concurrently, enhancing the C2H4/C2H6 separation performance of ZnAtzPO4/6FDA-DAM MMMs. This work generates a useful concept for the design and fabrication of high-performance MMMs.
Hui Wang,Yutao Liu,Yongheng Ren,Siyuan Peng,Jiayou Liao,Jinping Li,Libo Li
Membrane technology is a promising candidate for ethylene/ethane (C 2 H 4 /C 2 H 6 ) separation, but the separation factor and long-term stability of commercially available polymer membranes remain still insufficient to meet industrial requirements. Incorporating facilitated metal-ion carriers or unsaturated metal sites of fillers into polymers shows exceptional C 2 H 4 /C 2 H 6 separation efficiency due to the intensified olefin-favorable sorption . However, their separation performance usually dropped within a few hours due to the inactivation of the facilitated transport carrier or poisoning of unsaturated sites in presence of water vapor . Herein, we adopt a facile and effective method to prepare long-term stable Silicalite-1@Ag (S-1@Ag) mixed matrix membranes (MMM) by in-situ embedding the vulnerable carrier Ag + into the pores of the hydrophobic zeolite to protect the Ag + from deactivation. The 12 wt% S-1@Ag filler uniformly dispersing within the commercial 6FDA-DAM exhibits superior separation performance that surpasses the 2013 upper bound in terms of C 2 H 4 permeability of 29.74 barrer and C 2 H 4 /C 2 H 6 selectivity up to 7.66 for equimolar mixed gas. Furthermore, the hydrophobicity nature and framework shielding towards Ag + of S-1 guarantees the excellent almost 2-months stable separation of C 2 H 4 /C 2 H 6 by S-1@Ag MMMs under the high relative humidity conditions, demonstrating its potential for industrial applications.
Kangxin Bai,Yang Liu,Zhuangzhi Li,Jiajie Shi,Zhenggong Wang,Jian Jin
The separation of C2H4/C2H6 is crucial for the efficient production of C2H4. The energy-efficient membrane technology has great potential in this separation. However, the similar physical properties of the two molecules make them extremely difficult in membrane separation. Herein, a series of nanosized MOF-808 particles were incorporated into a polyimide matrix to fabricate mixed matrix membranes (MMMs) for C2H4/C2H6 separation. The well-defined pore architecture of MOF-808 enables effective C2H4 purification through molecular sieving, while the restricted diffusion of C2H6 molecules within the MOF-808 channels facilitates remarkable kinetic separation. Importantly, the nanosized MOF-808 can be dispersed more evenly in the polymer matrix, significantly improving the compatibility between the polymer matrix and filler, thereby maximizing the sieving effect of MOF-808. The resulting nanosized MOF-808-based MMM demonstrates a high C2H4 permeability of 1187 barrer and a C2H4/C2H6 selectivity of 2.8, which has exceeded most of the MMMs reported so far and surpassed the 2013 upper bound. Our MMMs also show excellent long-term stability and antiplasticization performance. Our work highlights the effectiveness of enhancing the separation performance of MMMs by using reducing nanosized MOF-808, providing valuable insights for the design of MMMs for C2H4/C2H6 separation.
危险品化学品经营许可证（带存储）