Magnetic mixed matrix membranes in air separation

AbstractEthylcellulose (EC) or linear polyimide (LPI) and magnetic neodymium powder particles MQP-14-12 were used for the preparation of inorganic-organic hybrid membranes. For all the membranes, N2, O2 and air permeability were examined. Mass transport coefficients were determined using the Time Lag System based on dynamic experiments in a constant pressure system. The results showed that the membrane permeation properties were improved by the addition of magnetic neodymium particles to the polymer matrix. The magnetic ethylcellulose and polyimide membranes exhibited higher gas permeability and diffusivity, while their permeability selectivity and solubility were either unchanged or slightly increased. Polyimide mixed matrix membranes were characterised by a higher thermal and mechanical stability, larger filler loading, better magnetic properties and reasonable selectivity in the air separation.

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Mixed Matrix Membranes Based on Torlon® and ZIF-8 for High-Temperature, Size-Selective Gas Separations

Membranes ◽

10.3390/membranes11120982 ◽

2021 ◽

Vol 11 (12) ◽

pp. 982

Author(s):

Matilde De Pascale ◽

Francesco Maria Benedetti ◽

Elsa Lasseuguette ◽

Maria-Chiara Ferrari ◽

Kseniya Papchenko ◽

...

Keyword(s):

Room Temperature ◽

Gas Permeability ◽

Filler Loading ◽

Glassy Polymers ◽

Gas Separations ◽

Mixed Matrix Membranes ◽

Size Selectivity ◽

Mixed Matrix ◽

Polymer Filler ◽

Matrix Membranes

Torlon® is a thermally and plasticization-resistant polyamide imide characterized by low gas permeability at room temperature. In this work, we aimed at improving the polymer performance in the thermally-enhanced He/CO2 and H2/CO2 separations, by compounding Torlon® with a highly permeable filler, ZIF-8, to fabricate Mixed Matrix Membranes (MMMs). The effect of filler loading, gas size, and temperature on the MMMs permeability, diffusivity, and selectivity was investigated. The He permeability increased by a factor of 3, while the He/CO2 selectivity decreased by a factor of 2, when adding 25 wt % of ZIF-8 at 65 °C to Torlon®; similar trends were observed for the case of H2. The MMMs permeability and size-selectivity were both enhanced by temperature. The behavior of MMMs is intermediate between the pure polymer and pure filler ones, and can be described with models for composites, indicating that such materials have a good polymer/filler adhesion and their performance could be tailored by acting on the formulation. The behavior observed is in line with previous investigations on MMMs based on glassy polymers and ZIF-8, in similar conditions, and indicates that ZIF-8 can be used as a polymer additive when the permeability is a controlling aspect, with a proper choice of loading and operative temperature.

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PEEK–WC-Based Mixed Matrix Membranes Containing Polyimine Cages for Gas Separation

Molecules ◽

10.3390/molecules26185557 ◽

2021 ◽

Vol 26 (18) ◽

pp. 5557

Author(s):

Marcello Monteleone ◽

Riccardo Mobili ◽

Chiara Milanese ◽

Elisa Esposito ◽

Alessio Fuoco ◽

...

Keyword(s):

Diffusion Coefficient ◽

Gas Separation ◽

Gas Permeability ◽

Time Lag ◽

Mixed Matrix Membranes ◽

Filler Materials ◽

Separation Performance ◽

Mixed Matrix ◽

Neat Polymer ◽

Matrix Membranes

Membrane-based processes are taking a more and more prominent position in the search for sustainable and energy-efficient gas separation applications. It is known that the separation performance of pure polymers may significantly be improved by the dispersion of suitable filler materials in the polymer matrix, to produce so-called mixed matrix membranes. In the present work, four different organic cages were dispersed in the poly(ether ether ketone) with cardo group, PEEK-WC. The m-xylyl imine and furanyl imine-based fillers yielded mechanically robust and selective films after silicone coating. Instead, poor dispersion of p-xylyl imine and diphenyl imine cages did not allow the formation of selective films. The H2, He, O2, N2, CH4, and CO2 pure gas permeability of the neat polymer and the MMMs were measured, and the effect of filler was compared with the maximum limits expected for infinitely permeable and impermeable fillers, according to the Maxwell model. Time lag measurements allowed the calculation of the diffusion coefficient and demonstrated that 20 wt % of furanyl imine cage strongly increased the diffusion coefficient of the bulkier gases and decreased the diffusion selectivity, whereas the m-xylyl imine cage slightly increased the diffusion coefficient and improved the size-selectivity. The performance and properties of the membranes were discussed in relation to their composition and morphology.

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Effect of new metal–organic framework (zeolitic imidazolate framework [ZIF-12]) in mixed matrix membranes on structure, morphology, and gas separation properties

Journal of Polymer Engineering ◽

10.1515/polyeng-2020-0288 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Mehtap Safak Boroglu ◽

Ismail Boz ◽

Busra Kaya

Keyword(s):

Gas Separation ◽

Gas Permeability ◽

Metal Organic Framework ◽

Thermomechanical Analysis ◽

Variable Pressure ◽

Mixed Matrix Membranes ◽

Mixed Matrix ◽

Sem Images ◽

Zeolitic Imidazolate Framework ◽

Matrix Membranes

Abstract In our study, the synthesis of zeolitic imidazolate framework (ZIF-12) crystals and the preparation of mixed matrix membranes (MMMs) with various ZIF-12 loadings were targeted. The characterization of ZIF-12 and MMMs were carried out by Fourier transform infrared spectroscopy analysis, thermogravimetric analysis, scanning electron microscopy (SEM), and thermomechanical analysis. The performance of MMMs was measured by the ability of binary gas separation. Commercial polyetherimide (PEI-Ultem® 1000) polymer was used as the polymer matrix. The solution casting method was utilized to obtain dense MMMs. In the SEM images of ZIF-12 particles, the particles with a rhombic dodecahedron structure were identified. From SEM images, it was observed that the distribution of ZIF-12 particles in the MMMs was homogeneous and no agglomeration was present. Gas permeability experiments of MMMs were measured for H2, CO2, and CH4 gases at steady state, at 4 bar and 35 °C by constant volume-variable pressure method. PEI/ZIF-12-30 wt% MMM exhibited high permeability and ideal selectivity values for H2/CH4 and CO2/CH4 were P H 2 / CH 4 = 331.41 ${P}_{{\text{H}}_{2}/{\text{CH}}_{4}}=331.41$ and P CO 2 / CH 4 = 53.75 ${P}_{{\text{CO}}_{2}/{\text{CH}}_{4}}=53.75$ gas pair.

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Predicting Gas Permeability through Mixed-matrix Membranes Filled with Nanofillers of Different Shapes

Arabian Journal for Science and Engineering ◽

10.1007/s13369-021-05996-8 ◽

2021 ◽

Author(s):

Muhammad Sarfraz ◽

Aqash Arshad ◽

M. Ba-Shammakh

Keyword(s):

Gas Permeability ◽

Mixed Matrix Membranes ◽

Mixed Matrix ◽

Different Shapes ◽

Matrix Membranes

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CO2 Selective, Zeolitic Imidazolate Framework-7 Based Polymer Composite Mixed-Matrix Membranes

Journal of Materials Science Research ◽

10.5539/jmsr.v7n3p1 ◽

2018 ◽

Vol 7 (3) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Tina Chakrabarty ◽

Pradeep Neelakanda ◽

Klaus-Viktor Peinemann

Keyword(s):

Metal Organic Framework ◽

Time Lag ◽

Morphological Characterization ◽

Mixed Matrix Membranes ◽

Co2 Removal ◽

Hybrid Membranes ◽

Mixed Matrix ◽

Zeolitic Imidazolate Framework ◽

Custom Made ◽

Matrix Membranes

CO2 removal is necessary to mitigate the effects of global warming but it is a challenging process to separate CO2 from natural gas, biogas, and other gas streams. Development of hybrid membranes by use of polymers and metal-organic framework (MOF) particles is a viable option to overcome this challenge. A ZIF-7 nano-filler that was synthesized in our lab was embedded into a designed polymer matrix at various loadings and the performance of the mixed matrix membranes was evaluated in terms of gas permeance and selectivity. Hybrid membranes with various loadings (20, 30 and 40 wt%) were developed and tested at room temperature by a custom made time lag equipment and a jump in selectivity was observed when compared with the pristine polymer. A commercially attractive region for the selectivity CO2 over CH4 was achieved with a selectivity of 39 for 40 wt% particle loading. An increase in selectivity was observed with the increase of ZIF-7 loadings. Best performance was seen at 40% ZIF-7 loaded membrane with an ideal selectivity of 39 for CO2 over CH4. The obtained selectivity was 105% higher for CO2 over CH4 than the selectivity of the pristine polymer with a slight decrease in permeance. Morphological characterization of such developed membranes showed an excellent compatibility between the polymer and particle adhesion.

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A Review on Computational Modeling Tools for MOF-Based Mixed Matrix Membranes

Computation ◽

10.3390/computation7030036 ◽

2019 ◽

Vol 7 (3) ◽

pp. 36 ◽

Cited By ~ 5

Author(s):

Keskin ◽

Alsoy Altinkaya

Keyword(s):

Computational Modeling ◽

Gas Permeability ◽

Gas Permeation ◽

Mixed Matrix Membranes ◽

Great Promise ◽

Mixed Matrix ◽

Modeling Tools ◽

Trade Off ◽

Membrane Materials ◽

Matrix Membranes

Computational modeling of membrane materials is a rapidly growing field to investigate the properties of membrane materials beyond the limits of experimental techniques and to complement the experimental membrane studies by providing insights at the atomic-level. In this study, we first reviewed the fundamental approaches employed to describe the gas permeability/selectivity trade-off of polymer membranes and then addressed the great promise of mixed matrix membranes (MMMs) to overcome this trade-off. We then reviewed the current approaches for predicting the gas permeation through MMMs and specifically focused on MMMs composed of metal organic frameworks (MOFs). Computational tools such as atomically-detailed molecular simulations that can predict the gas separation performances of MOF-based MMMs prior to experimental investigation have been reviewed and the new computational methods that can provide information about the compatibility between the MOF and the polymer of the MMM have been discussed. We finally addressed the opportunities and challenges of using computational studies to analyze the barriers that must be overcome to advance the application of MOF-based membranes.

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