Synthesis and gas permeation analysis of TiO2 nanotube-embedded cellulose acetate mixed 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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Effect of gas permeation temperature and annealing procedure on the performance of binary and ternary mixed matrix membranes of polyethersulfone, SAPO-34, and 2-hydroxy 5-methyl aniline

Journal of Applied Polymer Science ◽

10.1002/app.40679 ◽

2014 ◽

Vol 131 (17) ◽

pp. n/a-n/a ◽

Cited By ~ 8

Author(s):

Edibe Eda Oral ◽

Levent Yilmaz ◽

Halil Kalipcilar

Keyword(s):

Gas Permeation ◽

Mixed Matrix Membranes ◽

Mixed Matrix ◽

Annealing Procedure ◽

Matrix Membranes

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Synergistic solution of CO2 capture by novel lanthanide-based MOF-76 yttrium nanocrystals in mixed-matrix membranes

Energy & Environment ◽

10.1177/0958305x19882413 ◽

2019 ◽

Vol 31 (4) ◽

pp. 692-712 ◽

Cited By ~ 5

Author(s):

Sadia Bano ◽

Saadia R Tariq ◽

Ayesha Ilyas ◽

Muhammad Aslam ◽

Muhammad R Bilad ◽

...

Keyword(s):

Elevated Temperatures ◽

Metal Organic Framework ◽

Gas Permeation ◽

Mixed Matrix Membranes ◽

X Ray Diffraction ◽

Mixed Matrix ◽

The Family ◽

Metal Organic ◽

The Ideal ◽

Matrix Membranes

A porous and thermally stable metal organic framework (MOF) of yttrium and 1,3,5-benzenetricarboxylate was synthesized, which belongs to the family of lanthanide-based MOF-76. Mixed-matrix membranes were developed by incorporating MOF-76 yttrium nanocrystals into Matrimid® 5218. The structure, composition, and morphology of synthesized lanthanide-based MOF-76 yttrium nanocrystals and mixed-matrix membranes were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. The characterizations and gas permeation results of the prepared mixed-matrix membranes confirmed better adhesion and distribution of filler particles in the polymer. The results demonstrated that the addition of MOF-76 yttrium nanocrystals to the polymer matrix improved both the gas selectivity and permeability of mixed-matrix membranes compared to pure Matrimid membranes. Permeability of CO2 increased from 7.24 to 27.29 Barrer by increasing the particle content from 0 to 30% in pure gas experiments. Whereas with 30 wt% concentration of MOF-76(Y) at 50:50 feed compositions, the selectivity increased for CO2/CH4 and CO2/N2 was 67% and 68%, respectively. The rise in temperature from 298 to 338 K decreased the ideal selectivity up to 25% for both gas pairs due to polymer chain relaxations at elevated temperatures. The commercial importance of membranes was evaluated at different feed compositions and operating temperatures.

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Gas Transport in Mixed Matrix Membranes: Two Methods for Time Lag Determination

Computation ◽

10.3390/computation8020028 ◽

2020 ◽

Vol 8 (2) ◽

pp. 28 ◽

Cited By ~ 3

Author(s):

Alessio Fuoco ◽

Marcello Monteleone ◽

Elisa Esposito ◽

Rosaria Bruno ◽

Jesús Ferrando-Soria ◽

...

Keyword(s):

Transport Properties ◽

Gas Transport ◽

Time Lag ◽

Effective Diffusion ◽

Gas Permeation ◽

Mixed Matrix Membranes ◽

Mixed Matrix ◽

Mixed Gas ◽

Fitting Procedure ◽

Matrix Membranes

The most widely used method to measure the transport properties of dense polymeric membranes is the time lag method in a constant volume/pressure increase instrument. Although simple and quick, this method provides only relatively superficial, averaged data of the permeability, diffusivity, and solubility of gas or vapor species in the membrane. The present manuscript discusses a more sophisticated computational method to determine the transport properties on the basis of a fit of the entire permeation curve, including the transient period. The traditional tangent method and the fitting procedure were compared for the transport of six light gases (H2, He, O2, N2, CH4, and CO2) and ethane and ethylene in mixed matrix membranes (MMM) based on Pebax®1657 and the metal–organic framework (MOF) CuII2(S,S)-hismox·5H2O. Deviations of the experimental data from the theoretical curve could be attributed to the particular MOF structure, with cavities of different sizes. The fitting procedure revealed two different effective diffusion coefficients for the same gas in the case of methane and ethylene, due to the unusual void morphology in the MOFs. The method was furthermore applied to mixed gas permeation in an innovative constant-pressure/variable-volume setup with continuous analysis of the permeate composition by an on-line mass-spectrometric residual gas analyzer. This method can provide the diffusion coefficient of individual gas species in a mixture, during mixed gas permeation experiments. Such information was previously inaccessible, and it will greatly enhance insight into the mixed gas transport in polymeric or mixed matrix membranes.

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