Hydrogen Selective NH₂‐MIL‐53(Al) MOF Membranes with High Permeability

Abstract

Hydrogen‐based energy is a promising renewable and clean resource. Thus, hydrogen selective microporous membranes with high performance and high stability are demanded. Novel NH2‐MIL‐53(Al) membranes are evaluated for hydrogen separation for this goal. Continuous NH2‐MIL‐53(Al) membranes have been prepared successfully on macroporous glass frit discs assisted with colloidal seeds. The gas sorption ability of NH2‐MIL‐53(Al) materials is studied by gas adsorption measurement. The isosteric heats of adsorption in a sequence of CO2 > N2 > CH4 ≈ H2 indicates different interactions between NH2‐MIL‐53(Al) framework and these gases. As‐prepared membranes are measured by single and binary gas permeation at different temperatures. The results of singe gas permeation show a decreasing permeance in an order of H2 > CH4 > N2 > CO2, suggesting that the diffusion and adsorption properties make significant contributions in the gas permeation through the membrane. In binary gas permeation, the NH2‐MIL‐53(Al) membrane shows high selectivity for H2 with separation factors of 20.7, 23.9 and 30.9 at room temperature (288 K) for H2 over CH4, N2 and CO2, respectively. In comparison to single gas permeation, a slightly higher separation factor is obtained due to the competitive adsorption effect between the gases in the porous MOF membrane. Additionally, the NH2‐MIL‐53(Al) membrane exhibits very high permeance for H2 in the mixtures separation (above 1.5 × 10−6 mol m−2 s−1 Pa−1) due to its large cavity, resulting in a very high separation power. The details of the temperature effect on the permeances of H2 over other gases are investigated from 288 to 353 K. The supported NH2‐MIL‐53(Al) membranes with high hydrogen separation power possess high stability, resistance to cracking, temperature cycling and show high reproducibility, necessary for the potential application to hydrogen recycling.

Preparation of continuous NH2–MIL-53 membrane on ammoniated polyvinylidene fluoride hollow fiber for efficient H2 purification

“…Among different MOF membranes, the NH 2 -MIL-53 (composed of Al(III) and 2-amino terephthalic acid) membranes show high H 2 permeance and separation factors due to their unique features of gas adsorption [24]. So if we can grow the NH 2 -MIL-53 on polymeric hollow fiber, the separation performance of MOF membranes may further approach to the requirements of industry.…”

Zeolite membranes – a review and comparison with MOFs

“…This method has been widely reported. [315][316][317][318] There is also much progress in the prediction of pore size and functionalities of MOFs. In the so-called isoreticular chemistry, 319 desired topologies can be achieved by design and isoreticular series of compounds with the same topology but different pore sizes can be prepared.…”

Recent developments in membranes for efficient hydrogen purification

“…The modification only occurred on the ZIF-90 layer surface because the large APTES molecules could not enter the ZIF-90 layer. Consequently, there was nearly no variation of H 2 permeance before and after modification, and the as-modified membrane possessed a relatively high H 2 permeance of 842 GPU with the H 2 /CO 2 selectivity of 20 at 1 bar and 498 K. membrane using amino group containing organic ligand via colloidal assembly of MOF seeds method [134]. In the NH 2 -MIL-53(Al) membrane, an obviously stronger adsorption ability of CO 2 resulted in a longer retention time compared to H 2 because of the specific interaction between CO 2 molecules and amino groups.…”