Mixed matrix membranes based on MIL-101 metal–organic frameworks in polymer of intrinsic microporosity PIM-1

Abstract

This work presents a study on mixed matrix membranes (MMMs) of the polymer of intrinsic microporosity PIM-1, embedding the crystalline Cr-terephthalate metal-organic framework (MOF), known as MIL-101. Different kinds of MIL-101 were used: MIL-101 with an average particle size of ca. 0.2 µm, NanoMIL-101 (ca. 50 nm), ED-MIL-101 (MIL-101 functionalized with ethylene diamine) and NH 2 -MIL-101 (MIL-101 synthesized using 2aminoterephthalic acid instead of terephthalic acid). Permeability, diffusion and solubility coefficients and their corresponding ideal selectivities were determined for the gases He, H 2 , O 2 , N 2 , CH 4 and CO 2 on the "as-cast" samples and after alcohol treatment. The performance of the MMMs was evaluated in relation to the Maxwell model. The addition of NH 2 -MIL-101 and ED-MIL-101 does not increase the membrane performance for the CO 2 /N 2 and CO 2 /CH 4 separation because of an initial decrease in selectivity at low MOF content, whereas the O 2 and N 2 permeability both increase for NH 2 -MIL-101. In contrast, MIL-101 and NanoMIL-101 cause a strong shift to higher permeability in the Robeson diagrams for all gas pairs, especially for CO 2 , without significant change in selectivity. Unprecedented CO 2 permeabilities up to 35,600 Barrer were achieved, which are among the highest values reached with PIM-1 based mixed matrix membranes. For various gas pairs, the permeability and selectivity were far above the Robeson upper bound after alcohol treatment. Short to 21/11/2018 16.36.31 PIM-MIL-101 manuscript_SEPPUR_Final_revised_clean.docx p. 2/24 medium time aging shows that alcohol treated samples with MIL-101 maintain a systematically higher permeability in time. Mixed gas permeation experiments on an aged ascast sample with 47 vol% MIL-101 reveal that the MMM sample maintains an excellent combination of permeability and selectivity, far above the Robeson upper bound (CO 2 =3,500-3,800 Barrer, CO 2 /N 2 = 25-27; CO 2 /CH 4 =21 -24). This suggests good perspectives for these materials in thin film composite membranes for real applications.

Gas Permeable Mixed Matrix Membranes Composed of a Polymer of Intrinsic Microporosity (PIM-1) and Surface-modified Pearl-necklace Silica Nanoparticles: Effect of Expansion of Nano-space on Gas Permeability

“…MMMs containing porous materials, such as zeolite [3][4][5][6] and metal organic frameworks (MOF) [7,8], have been studied to improve gas permeability and gas selectivity. Several studies have succeeded in developing gas permeation properties exceeding Robeson's upper bound [9,10]. On the other hand, it has been reported that MMMs with non-porous particles have also improved gas permeability [11][12][13].…”

High Performance of PIM-1/ZIF-8 Composite Membranes for O2/N2 Separation

“…6,7 With different metal–organic frameworks (MOFs) introduced into PIM-1, the corresponding MMMs have shown excellent gas separation performance. 8−10 Particularly, the MMM based on PIM-1 and zeolitic imidazolate framework (ZIF-8), the O 2 and N 2 permeability were increased by 190 and 94%, respectively; meanwhile, the O 2 /N 2 selectivity was increased by 50%. 11 However, the poor compatibility between polymer substrates and MOF particles usually leads to nonuniform distribution of particles, especially for MMMs with high filler loading, and it may cause agglomeration and poor mechanical properties.…”

Polymer-Based Shaping Strategy for Zeolite Templated Carbons (ZTC) and Their Metal Organic Framework (MOF) Composites for Improved Hydrogen Storage Properties

“…Several other studies have also reported on other types of MOF/Carbon composites such as MOF-5/expanded natural graphite (ENG) (Liu et al, 2012), MIL-101(Cr)/ZTC (Musyoka et al, 2016) and HKUST-1/graphene platelets (Hassan et al, 2019). Additionally, other MOF/polymer composites such as PIM-1/MIL-101 (Cr) (Khdhayyer et al, 2019), PIM-1/UiO-66 (Khdhayyer et al, 2017), PIM-1/UiO-66-NH 2 (Tien-Binh et al, 2018), PIM-1/UiO-66- CN (Yu et al, 2019) and Matrimid/UiO-66 MMMs (Marti et al, 2018) have been reported. However, no work has been done on composites materials consisting of the three pristine materials (carbon/polymer/MOF) for H 2 adsorption applications.…”