Improved CO2/CH4 Separation Properties of Cellulose Triacetate Mixed–Matrix Membranes with CeO2@GO Hybrid Fillers

The study of the effects associated with the compatibility of the components of the hybrid filler with polymer matrix, which ultimately decide on achieving mixed matrix membranes (MMMs) with better gas separation properties, is essential. Herein, a facile solution casting process of simple incorporating CeO2@GO hybrid inorganic filler material is implemented. Significant improvements in material and physico-chemical properties of the synthesized membranes were observed by SEM, XRD, TGA, and stress-strain measurements. Usage of graphene oxide (GO) with polar groups on the surface enabled forming bonds with ceria (CeO2) nanoparticles and CTA polymer and provided the homogeneous dispersion of the nanofillers in the hybrid MMMs. Moreover, increasing GO loading concentration enhanced both gas permeation in MMMs and CO2 gas uptakes. The best performance was achieved by the membrane containing 7 wt.% of GO with CO2 permeability of 10.14 Barrer and CO2/CH4 selectivity 50.7. This increase in selectivity is almost fifteen folds higher than the CTA-CeO2 membrane sample, suggesting the detrimental effect of GO for enhancing the selectivity property of the MMMs. Hence, a favorable synergistic effect of CeO2@GO hybrid fillers on gas separation performance is observed, propounding the efficient and feasible strategy of using hybrid fillers in the membrane for the potential biogas upgrading process.

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Investigation of the silica pore size effect on the performance of polysulfone (PSf) mixed matrix membranes (MMMs) for gas separation

Journal of Polymer Engineering ◽

10.1515/polyeng-2021-0055 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Gholamhossein Vatankhah ◽

Babak Aminshahidy

Keyword(s):

Mesoporous Silica ◽

Pore Size ◽

Gas Separation ◽

Gas Permeation ◽

Mixed Matrix Membranes ◽

Separation Performance ◽

Mixed Matrix ◽

Small Pore ◽

Mcm 41 ◽

Matrix Membranes

Abstract MCM-41 and SBA-15 mesoporous silica materials with different pore sizes (3.08 nm for small pore size MCM-41 (P 1), 5.89 nm for medium pore size SBA-15 (P 2), and 7.81 nm for large pore size SBA-15 (P 3)) were synthesized by the hydrothermal method and then functionalized with 3-aminopropyltrietoxysilane by postsynthesis treatments. Next, polysulfone-mesoporous silica mixed matrix membranes (MMMs) were prepared by the solution casting method. The obtained materials and MMMs were characterized by various techniques including X-ray diffraction, scanning electron microscopy, and N2 adsorption-desorption, and Brunauer-Emmett-Teller method to examine the crystallinity, morphology, and particle size, pore volume, specific surface area, and pore size distribution, respectively. Finally, the gas permeation rates of prepared MMMs were measured in 8 bar and 25 °C and the effect of pore size of modified and unmodified mesoporous silica on the gas separation performance of these MMMs were investigated. The experimental results indicate that the carbon dioxide (CO2) and methane (CH4) permeability and CO2/CH4 selectivity were increased with an enhancement in the particle pore size.

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Preparation of Mixed Matrix Membranes Containing ZIF-8 and UiO-66 for Multicomponent Light Gas Separation

Crystals ◽

10.3390/cryst9010015 ◽

2018 ◽

Vol 9 (1) ◽

pp. 15 ◽

Cited By ~ 3

Author(s):

Eun Kim ◽

Hyun Kim ◽

Donghwi Kim ◽

Jinsoo Kim ◽

Pyung Lee

Keyword(s):

Gas Separation ◽

Gas Permeation ◽

Polymer Membrane ◽

Mixed Matrix Membranes ◽

Gas Mixture ◽

Separation Performance ◽

Mixed Matrix ◽

Neat Polymer ◽

H2 Permeability ◽

Matrix Membranes

Mixed matrix membranes (MMMs) containing zeolitic imidazolite framework-8 (ZIF-8) and UiO-66 as microporous fillers were prepared and evaluated their potential for the separation of a gas mixture produced by a methane reforming process. Hydrothermal synthesis was performed to prepare both the ZIF-8 and UiO-66 crystals, with crystal sizes ranging from 50 to 70 nm for ZIF-8 and from 200 to 300 nm for UiO-66. MMMs were prepared with 15% filler loading for both MMM (ZIF-8) and MMM (UiO-66). MMM (UiO-66) exhibited H2 permeability of 64.4 barrer and H2/CH4 selectivity of 153.3 for single gas permeation, which are more than twice the values that were exhibited by a neat polymer membrane. MMM (ZIF-8) also showed better separation properties than that of a neat polymer membrane with H2 permeability of 27.1 barrer and H2/CH4 selectivity of 123.2. When a gas mixture consisting of 78% Ar/18% H2/4% CH4 flowed into the membranes at 5 bar, the H2 purity increased to as high as 93%. However, no improvement in the mixture gas separation performance was achieved by the MMMs as compared to that of a neat polymer membrane.

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CARBON DIOXIDE/METHANE SEPARATION PERFORMANCE BY MIXED MATRIX MEMBRANE FROM POLYSULFONE/ HALLOYSITE NANOTUBES

Jurnal Teknologi ◽

10.11113/jt.v82.14309 ◽

2020 ◽

Vol 82 (3) ◽

Author(s):

Noor Maizura Ismail ◽

Nur Afaliza Yusaini ◽

Jannah Jafa ◽

S. M. Anisuzzaman ◽

Chiam Chel Ken ◽

...

Keyword(s):

Gas Separation ◽

Halloysite Nanotubes ◽

Skin Layer ◽

Gas Permeation ◽

Mixed Matrix Membranes ◽

Inorganic Filler ◽

Mixed Matrix Membrane ◽

Separation Performance ◽

Mixed Matrix ◽

Morphological Differences

Gas separation by using membrane-based technology is one of the rising technologies used in the industry. It has many advantages such as low in cost and energy consumption. However, this technology is limited because of the "trade-off" exists between permeability and selectivity of the membrane. Thus, in this study, an inorganic filler, halloysite nanotube is modified with 3-aminopropyl(triethoxysilane) and then incorporated into the polysulfone polymer and the performance of the mixed matrix membranes (MMMs) is investigated. MMMs were analyzed by using SEM, FTIR, tensile and gas permeation tests which studied the morphological differences, mechanical strength, and membrane permeability and selectivity towards CO2 and CH4 respectively. The performance of the MMMs was compared with neat membrane and MMMs with unmodified HNTs. SEM results show an increase of 111% on the thickness of the dense skin layer of MMMs with APTES-modified HNTs compared to the neat membrane and the MMMs with unmodified HNTs. Elongation at break for MMMs with 3-APTES-modified HNTs also increased to 24.22%. The gas separation performance of the MMMs with 3-APTES modified HNTs shows an overall increase of 25.37% in the membrane selectivity compared to MMMs with unmodified HNTs while when coating is done, the selectivity of the MMMs with 3-APTES modified HNTs shows an increase from 0.845 to 10.158 for a pressure of 2 bar showing that coating helps in increasing the selectivity of the membrane.

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CO2/CH4 and H2/CH4 Gas Separation Performance of CTA-TNT@CNT Hybrid Mixed Matrix Membranes

Membranes ◽

10.3390/membranes11110862 ◽

2021 ◽

Vol 11 (11) ◽

pp. 862

Author(s):

Chhabilal Regmi ◽

Saeed Ashtiani ◽

Zdeněk Hrdlička ◽

Karel Friess

Keyword(s):

Natural Gas ◽

Gas Separation ◽

Mixed Matrix Membranes ◽

Separation Performance ◽

Co2 Uptake ◽

Gas Purification ◽

Mixed Matrix ◽

Natural Gas Purification ◽

Hybrid Fillers ◽

Matrix Membranes

This study explored the underlying synergy between titanium dioxide nanotube (TNT) and carbon nanotube (CNT) hybrid fillers in cellulose triacetate (CTA)-based mixed matrix membranes (MMMs) for natural gas purification. The CNT@TNT hybrid nanofillers were blended with CTA polymer and cast as a thin film by a facile casting technique, after which they were used for single gas separation. The hybrid filler-based membrane depicted a higher CO2 uptake affinity than the single filler (CNT/TNT)-based membrane. The gas separation results indicate that the hybrid fillers (TNT@CNT) are strongly selective for CO2 over CH4 and H2 over CH4. The increment in the CO2/CH4 and H2/CH4 selectivities compared to the pristine CTA membrane was 42.98 from 25.08 and 48.43 from 36.58, respectively. Similarly, the CO2 and H2 permeability of the CTA-TNT@CNT membrane increased by six- and five-fold, respectively, compared to the pristine CTA membrane. Such significant improvements in CO2/CH4 and H2/CH4 separation performance and thermal and mechanical properties suggest a feasible and practical approach for potential biogas upgrading and natural gas purification.

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Functionalized KIT-6/Polysulfone Mixed Matrix Membranes for Enhanced CO2/CH4 Gas Separation

Polymers ◽

10.3390/polym12102312 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2312

Author(s):

Thiam Leng Chew ◽

Sie Hao Ding ◽

Pei Ching Oh ◽

Abdul Latif Ahmad ◽

Chii-Dong Ho

Keyword(s):

Gas Separation ◽

Gas Permeation ◽

Mixed Matrix Membranes ◽

Separation Performance ◽

X Ray Diffraction ◽

Mixed Matrix ◽

X Ray ◽

The Matrix ◽

Adsorption Desorption ◽

Matrix Membranes

The development of mixed matrix membranes (MMMs) for effective gas separation has been gaining popularity in recent years. The current study aimed at the fabrication of MMMs incorporated with various loadings (0–4 wt%) of functionalized KIT-6 (NH2KIT-6) [KIT: Korea Advanced Institute of Science and Technology] for enhanced gas permeation and separation performance. NH2KIT-6 was characterized by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and N2 adsorption–desorption analysis. The fabricated membranes were subjected to FESEM and FTIR analyses. The effect of NH2KIT-6 loading on the CO2 permeability and ideal CO2/CH4 selectivity of the fabricated membranes were investigated in gas permeation and separation studies. The successfulness of (3-Aminopropyl) triethoxysilane (APTES) functionalization on KIT-6 was confirmed by FTIR analysis. As observed from FESEM images, MMMs with no voids in the matrix were successfully fabricated at a low NH2KIT-6 loading of 0 to 2 wt%. The CO2 permeability and ideal CO2/CH4 selectivity increased when NH2KIT-6 loading was increased from 0 to 2 wt%. However, a further increase in NH2KIT-6 loading beyond 2 wt% led to a drop in ideal CO2/CH4 selectivity. In the current study, a significant increase of about 47% in ideal CO2/CH4 selectivity was achieved by incorporating optimum 2 wt% NH2KIT-6 into the MMMs.

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A Prospective Concept on the Fabrication of Blend PES/PEG/DMF/NMP Mixed Matrix Membranes with Functionalised Carbon Nanotubes for CO2/N2 Separation

Membranes ◽

10.3390/membranes11070519 ◽

2021 ◽

Vol 11 (7) ◽

pp. 519

Author(s):

Ashvin Viknesh Mahenthiran ◽

Zeinab Abbas Jawad

Keyword(s):

Gas Separation ◽

Fossil Fuels ◽

Void Formation ◽

Chemical Properties ◽

Mixed Matrix Membranes ◽

Separation Performance ◽

Mixed Matrix ◽

Carbon Dioxide Co2 ◽

The Impact ◽

Matrix Membranes

With an ever-increasing global population, the combustion of fossil fuels has risen immensely to meet the demand for electricity, resulting in significant increase in carbon dioxide (CO2) emissions. In recent years, CO2 separation technology, such as membrane technology, has become highly desirable. Fabricated mixed matrix membranes (MMMs) have the most desirable gas separation performances, as these membranes have the ability to overcome the trade-off limitations. In this paper, blended MMMs are reviewed along with two polymers, namely polyether sulfone (PES) and polyethylene glycol (PEG). Both polymers can efficiently separate CO2 because of their chemical properties. In addition, blended N-methyl-2-pyrrolidone (NMP) and dimethylformamide (DMF) solvents were also reviewed to understand the impact of blended MMMs’ morphology on separation of CO2. However, the fabricated MMMs had challenges, such as filler agglomeration and void formation. To combat this, functionalised multi-walled carbon nanotube (MWCNTs-F) fillers were utilised to aid gas separation performance and polymer compatibility issues. Additionally, a summary of the different fabrication techniques was identified to further optimise the fabrication methodology. Thus, a blended MMM fabricated using PES, PEG, NMP, DMF and MWCNTs-F is believed to improve CO2/nitrogen separation.

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