Samenvatting
Double-layered zeolitic imidazolate framework (ZIF) membranes were fabricated inside polyimide P84 hollow fibers by a step-synthesis conducted by microfluidic technology and applied to pre-combustion gas separation. Our hypothesis, based on the information provided by a combination of molecular simulation and experiments, is that a CO2 adsorption reduction on the surface of the ZIF-9 would enhance the molecular sieving effect of this ZIF-9 layer and therefore the selectivity in the H2/CO2 mixture separation of the entire membrane. This reduction would be achieved by means of a less-CO2-adsorptive methylimidazolate-based ZIF-67 or ZIF-8 layer coating the ZIF-9. ZIF-8/ZIF-9 and ZIF-67/ZIF-9 double-layered membranes were prepared and characterized by XRD, FTIR, SEM, FIB, TEM and EDS. This unprecedented strategy led to a H2/CO2 separation selectivity of 9.6 together with a 250 GPU H2 permeance at 150 °C, showing a significant improvement with respect to the pure ZIF-9 membrane. Double-layered membranes also showed higher apparent CO2 activation energies than single-layered membranes, attributable to a diminished adsorption.
| Originele taal-2 | Engels |
|---|---|
| Pagina's (van-tot) | 325-333 |
| Aantal pagina's | 9 |
| Tijdschrift | Chemical Science |
| Volume | 8 |
| Nummer van het tijdschrift | 1 |
| DOI's | |
| Status | Gepubliceerd - 1 jul. 2017 |
| Extern gepubliceerd | Ja |
Financiering
Financial support (MAT2013-40556-R) from the Spanish MINECO, the Arag?n Government (DGA, T05) and the European Social Fund is gratefully acknowledged. We also acknowledge the use of the Servicio General de Apoyo a la Investigaci?n-SAI (Universidad de Zaragoza). F. C.-B. acknowledges his DGA predoctoral fellowship. V. S. acknowledges the support of the People Program (CIG-Marie Curie Actions, REA grant agreement no. 321642). I. M.-M. thanks the Spanish MINECO for his predoctoral fellowship. The European Research Council through an ERC Grant (ERC2011-StG-279520-RASPA) is also acknowledged. All the microscopy work was done in the Laboratorio de Microscop?as Avanzadas at the Instituto de Nanociencia de Arag?n (LMA-INA). The authors acknowledge the LMA-INA for offering access to their instruments and expertise.