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gas-separation
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Supersonic Separation
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali (Supervisor) ; Nouri Borujerdi, Ali (Supervisor)
Abstract
Supersonic separators with neither rotating parts nor chemical process, physically separate particles in a multi-phase flow. In comparison with general separation techniques, which are utilized in industries, specifically this equipment is cheaper, smaller and lighter. Condensation and separation at supersonic velocity is the key to achieve a significant reduction in both capital and operating costs. In this study, a two dimensional de Laval nozzle and few three-dimensional supersonic separator have been modeled. The 3D models modified in shape and dimensions. Impellers were created to form swirl flow. The models were simulated by the use of CFD software ANSYS FLUENT. Diverse inlet pressures...
Effect of the wet outlet geometry on the shockwave position in supersonic separators
, Article Chemical Engineering and Technology ; Volume 43, Issue 1 , January , 2020 , Pages 126-136 ; Farhadi, F ; Sharif University of Technology
Wiley-VCH Verlag
2020
Abstract
Supersonic separators (3Ss) are applied in gas separation processes. Two-dimensional simulation is employed to investigate the effect of operational and thermophysical parameters on the shockwave position. In addition, the impact of the cyclonic part and wet outlet geometry is evaluated by proposing four cases. Increasing the length of the cyclonic part exerts positive and negative influences on the performance of the 3S and the pressure recovery coefficient, respectively. The optimum length is determined between 10 and 15 cm. To demonstrate negative effects of wasted air from the wet outlet, its flow has been increased from 3.6 to 8.1 % of the inlet flow. Improved performance of the 3S is...
Fabrication and evaluation of nanocomposite membranes of polyethersulfone/α-alumina for hydrogen separation
, Article Iranian Polymer Journal (English Edition) ; Volume 24, Issue 3 , 2015 , Pages 171-183 ; 10261265 (ISSN) ; Rashidzadeh, M ; Safekordi, A ; Khanbabaei, G ; Sharif University of Technology
Springer-Verlag London Ltd
2015
Abstract
In this study, polyethersulfone (PES)-based nanocomposite membranes with the incorporation of inorganic filler of α-alumina were prepared via thermal phase inversion method. The fabricated flat sheet-mixed matrix membranes were characterized using X-ray diffraction, thermal gravimetric analysis, differential scanning calorimetry, scanning electron microscopy, and atomic force microscope analysis, and the permeation tests were performed for hydrogen, nitrogen and carbon dioxide. Also prepared α-alumina particles were identified by X-ray diffraction and the surface area, total pore volume and average pore diameter of particles were measured with a high-speed gas-sorption analyzer. The...
Effect of silica nanoparticles on carbon dioxide separation performances of PVA/PEG cross-linked membranes
, Article Chemical Papers ; Volume 75, Issue 7 , 2021 , Pages 3131-3153 ; 03666352 (ISSN) ; Islam, A ; Haider, B ; Sajid, M ; Ijaz, A ; Khan, R. U ; Khan, W. G ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Novel PVA/PEG cross-linked membranes were prepared with (0–20 wt. %) of silica nanoparticles. The presence of both the polymers and additive was confirmed by FTIR analysis. The thermal properties of the membranes were analyzed by TGA and DSC analysis. The morphological and mechanical properties of the membranes were studied by SEM analysis and tensile testing, respectively. The gas permeation performances of the membranes were examined using state-of-the-art gas permeability cell. It was found that permeability of all the gases increased with the increase of silica loading, whereas ideal selectivity of carbon dioxide with respect to nitrogen and methane increased up to 10 wt. % loading and...
Development of porous nanocomposite membranes for gas separation by identifying the effective fabrication parameters with Plackett–Burman experimental design
, Article Journal of Porous Materials ; Volume 23, Issue 5 , 2016 , Pages 1279-1295 ; 13802224 (ISSN) ; Safekordi, A ; Rashidzadeh, M ; Khanbabaei, G ; Akbari Anari, R ; Rahimpour, M ; Sharif University of Technology
Springer New York LLC
2016
Abstract
In this research, Plackett–Burman experimental design was used as a screening method to investigate seven processing factors in the preparation of new polyethersulfone based porous nanocomposite membrane. Polymer concentration, nanoparticle type, nanoparticle concentration, solvent type, solution mixing time, evaporation time, and annealing temperature are variables that were evaluated to fabricate mixed matrix membranes using the evaporation phase inversion method for gas separation. According to obtained results, polymer concentration, nanoparticle concentration, solution mixing time, and evaporation time processing factors had significant effects on gas permeation. In addition, the...
Thin film graphene oxide membrane: challenges and gas separation potential
, Article Korean Journal of Chemical Engineering ; Volume 35, Issue 5 , May , 2018 , Pages 1174-1184 ; 02561115 (ISSN) ; Karimi Sabet, J ; Ghotbi, C ; Abbasi, Z ; Sharif University of Technology
Springer New York LLC
2018
Abstract
Graphene oxide membranes were prepared by vacuum and pressurized ultrafiltration methods on the 12% modified Polyacrylonitrile (12mPAN) substrate to specify challenges, salient features, future directions, and potential of GO membrane for separation fields using characterization techniques and gas separation test (studied gases are CO2, He and N2), which is an efficient tool for better understanding of GO membrane behavior. GO membrane structure was examined over a wide range of parameters, such as pore size range of substrate and its surface properties, pH of GO dispersion, GO content, synthesis pressure, operating pressure and temperature. The results show that the GO content does not hold...
Gas separation properties of crosslinked and non-crosslinked carboxymethylcellulose (CMC) membranes
, Article Scientia Iranica ; Volume 20, Issue 6 , 2013 , Pages 1921-1928 ; 10263098 (ISSN) ; Shafiabadi, N ; Mousavi, S. A ; Amini-Fazl, M. S ; Sharif University of Technology
Sharif University of Technology
2013
Abstract
In this study, crosslinked and non-crosslinked carboxymethylcellulose (CMC) membranes were prepared with different concentrations of polymer. Then, the permeability of pure CO2 , N2 , and CH4 was measured through these membranes in dry state to investigate the influence of polymer concentration and applied feed pressure on permeability and permselectivity. The permeability of CO2 through membranes was higher than the other gases. A comparison of permeabilities revealed that the permeability of N2 , CO2 , and CH4 increased on an average of 33, 40 and 20 percent, respectivly, by increasing the feed pressure from 6 to 10...
Amino-silane-grafted NH2-MIL-53(Al)/polyethersulfone mixed matrix membranes for CO2/CH4 separation
, Article Dalton Transactions ; Volume 48, Issue 36 , 2019 , Pages 13555-13566 ; 14779226 (ISSN) ; Ahmadipouya, S ; Molavi, H ; Arjmand, M ; Sharif University of Technology
Royal Society of Chemistry
2019
Abstract
Mixed-matrix membranes (MMMs) are promising candidates for carbon dioxide separation. However, their application is limited due to improper dispersion of fillers within the polymer matrix, poor interaction of fillers with polymer chains, and formation of defects and micro-voids at the interface of both phases, which all result in the decline of the gas separation performance of MMMs. In this work, we present a new method to overcome these challenges. To this end, a series of MMMs based on polyethersulfone (PES) as the continuous polymer matrix and MIL-53-derived MOFs as the dispersed filler were prepared. FTIR-ATR, XRD, TGA, FESEM, and N2 adsorption/desorption analyses were employed to...
Gas permeation and sorption properties of poly(amide-12-b-ethyleneoxide)(Pebax1074)/SAPO-34 mixed matrix membrane for CO2 /CH4 and CO2 /N2 separation
,
Article
Journal of Industrial and Engineering Chemistry
;
Volume 27
,
July
,
2015
,
Pages 223-239
;
1226086X (ISSN)
; Meshkat Alsadat, S
; Soltanieh, M
; Mousavi, S. A
; Ghadimi, A
;
Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2015
Abstract
Zeolite SAPO-34 was used for fabrication of mixed matrix membranes (MMMs) to improve the CO2 /CH4 /N2 gas separation performance of the neat Pebax1074 membrane. Permeability and selectivity of the MMMs were studied at different temperatures of 25-65°C and pressures of 4-24 bars. Also sorption of different gases in MMMs was measured at 35°C and different pressures, which showed enhanced solubility coefficients. Moreover, thermal, morphological and mechanical properties of MMMs were characterized by differential scanning calorimetry (DSC), scanning electron microscope (SEM) and tensile analysis. The results showed excellent improvement in...
Effect of reactive diluent on gas separation behavior of photocurable acrylated polyurethane composite membranes
, Article Journal of Applied Polymer Science ; Volume 137, Issue 3 , 15 January , 2020 ; Shojaei, A ; Mousavi, S. A ; Ahmadi, S. A ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
In this study, the effects of the type and content of reactive diluents on the permeation/separation of carbon dioxide/nitrogen (CO2/N2) through acrylate-terminated polyurethane (APU)-acrylate/acrylic diluent (APUA) composite membranes was investigated. A series of APUs based on poly(ethylene glycol) (PEG)-1000 g mol−1, toluene diisocyanate, and 2-hydroxyethyl methacrylate was synthesized and then diluted with several reactive diluents. The results obtained from differential scanning calorimetry (DSC) and Fourier transform infrared analyses showed that the microphase interference of hard and soft segments increased with increasing reactive diluent content. Furthermore, with increasing alkene...
CO2/CH4 separation by mixed-matrix membranes holding functionalized NH2-MIL-101(Al) nanoparticles: Effect of amino-silane functionalization
, Article Chemical Engineering Research and Design ; Volume 176 , 2021 , Pages 49-59 ; 02638762 (ISSN) ; Ahmadijokani, F ; Molavi, H ; Rezakazemi, M ; Arjmand, M ; Sharif University of Technology
Institution of Chemical Engineers
2021
Abstract
In this study, NH2-MIL-101(Al) metal-organic frameworks (MOFs) covered with 3-aminopropyltriethoxysilane (APTES) were incorporated into the polyethersulfone (PES) to produce mixed-matrix membranes (MMMs) for CO2 separation. The APTES functionalization was performed to improve the MOF dispersion in the PES matrix. Different analyses such as X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM) revealed that the MOFs surface successfully functionalized with APTES. An improvement in CO2/CH4 separation efficiency was observed in MMMs, and the performance...
CO2/CH4 separation by mixed-matrix membranes holding functionalized NH2-MIL-101(Al) nanoparticles: Effect of amino-silane functionalization
, Article Chemical Engineering Research and Design ; Volume 176 , 2021 , Pages 49-59 ; 02638762 (ISSN) ; Ahmadijokani, F ; Molavi, H ; Rezakazemi, M ; Arjmand, M ; Sharif University of Technology
Institution of Chemical Engineers
2021
Abstract
In this study, NH2-MIL-101(Al) metal-organic frameworks (MOFs) covered with 3-aminopropyltriethoxysilane (APTES) were incorporated into the polyethersulfone (PES) to produce mixed-matrix membranes (MMMs) for CO2 separation. The APTES functionalization was performed to improve the MOF dispersion in the PES matrix. Different analyses such as X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM) revealed that the MOFs surface successfully functionalized with APTES. An improvement in CO2/CH4 separation efficiency was observed in MMMs, and the performance...
Photo-curable acrylate polyurethane as efficient composite membrane for CO2 separation
, Article Polymer ; Volume 149 , 2018 , Pages 178-191 ; 00323861 (ISSN) ; Shojaei, A ; Mousavi, S. A ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The current investigation was to present composite membranes with strong interfacial adhesion between top polymeric selective layer and the bottom micro-porous support layer with appropriate gas permeation behavior and practically suitable processing characteristics. To this end, a series of acrylate-terminated polyurethanes (APUs) based on poly (ethylene glycol) (PEG) with different molecular weights (Mn) of 600, 1000, 1500, 2000 and 4000 g/mol, toluene diisocyanate (TDI), and 2-hydroxyethyl methacrylate (HEMA) were synthesized. Composite membranes were prepared with UV-curable acrylate-terminated polyurethane/acrylate diluent (APUAs) as selective layer and polyester/polysulfone (PS/PSF) as...
Mass transfer through PDMS/zeolite 4A MMMs for hydrogen separation: Molecular dynamics and grand canonical Monte Carlo simulations
, Article International Communications in Heat and Mass Transfer ; Volume 108 , 2019 ; 07351933 (ISSN) ; Amirkhani, F ; Khadem, S. A ; Rezakazemi, M ; Asghari, M ; Shirazian, S ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In industry, utilizing membrane separation technology to purify natural gas streams is of remarkable significance. Molecular Simulation was used in the current article to study the structural and gas separation properties of polydimethylsiloxane (PDMS)/zeolite 4A Mixed Matrix Membranes (MMMs). To explore the optimal performance of MMMs, several structural analyses, namely Fractional Free Volume (FFV), Radial Distribution Function (RDF), X-Ray Diffraction (XRD) and also Glass Transition Temperature (Tg) as one of the most important properties of membranes have been evaluated. Also, the solubilities and diffusivities of periodic cells were respectively measured using MSD and adsorption...
LPG mass separation by vortex tube cascade and its economics
, Article Applied Thermal Engineering ; Volume 148 , 2019 , Pages 1139-1147 ; 13594311 (ISSN) ; Alighardashi, H ; Farhadi, F ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In the present experimental study, the effect of operating parameters such as inlet and outlet pressure as well as inlet temperature on the mass separation capability of vortex tubes (VTs) for a gas mixture is investigated. Specifically, concentrating heavier components of a gas mixture in the hot outlet stream is considered. Proposing a semi-empirical index from the experimental study, the simulation of different arrangements of VTs, and the effect of recycling a portion of the hot outlet stream on its mass separation performance are investigated. Moreover, the proposed separation method by VTs is economically compared with commonly used methods by distillation columns and two-phase...
Supersonic separator's dehumidification performance with specific structure: Experimental and numerical investigation
, Article Applied Thermal Engineering ; Volume 179 , October , 2020 ; Farhadi, F ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Supersonic separators are used in gas separation processes such as dehumidification of humid air due to high performance and its good pressure recovery. In the present study, a comprehensive numerical and experimental investigation on the hydrodynamic behavior of air as working fluid and dehumidification performance of supersonic separator have been accomplished. The effect of the operational parameters on shockwave's position are examined. The outcomes show that by increasing the pressure level of supersonic separator, relative error between numerical and experimental results decreases from 20% to less than 10%. The effect of the operational parameters and humidity of inlet air on the...
Effect of alumina on the performance and characterization of cross-linked PVA/PEG 600 blended membranes for CO2/N2 separation
, Article Separation and Purification Technology ; Volume 210 , 2019 , Pages 627-635 ; 13835866 (ISSN) ; Islam, A ; Hamidullah, U ; Jamshaid, F ; Ahmad, A ; Zahid Butt, M. T ; Ijaz, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this work, poly(vinyl) alcohol (PVA)/poly(ethylene) glycol (PEG) 600 g/mol cross-linked membranes with different alumina (Al2O3) content were synthesized. The membranes were then characterized by FTIR, TGA, DSC, SEM, mechanical strength and permeation properties for carbon dioxide and nitrogen gases at different operating temperatures. The FTIR results confirmed the acetal linkages of cross-linking at 1083 cm−1 and the presence of stretching and bending peaks of Al-O bond at 598 and 444 cm−1, respectively. TGA results showed that the thermal stabilities of the membranes improved with the addition of alumina particles. DSC analysis proved that the glass transition temperature of the...
Swirl intensity as a control mechanism for methane purification in supersonic gas separators
, Article Journal of Natural Gas Science and Engineering ; Volume 83 , 2020 ; Amini Magham, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Supersonic gas separator is proposed for methane purification. One-dimensional analysis is performed to examine the design aspects associated with the converging-diverging nozzle and the liquid separation chamber. The results indicate that at low swirl intensities, the separation chamber length is about 100 times of the nozzle throat. Increasing the swirl intensity would lower this length sharply and it will be less than 10 for swirl intensity of unity which is equivalent to a swirl angle of 45°. In addition, a sensitivity analysis of the separator performance to the inlet conditions like the temperature, pressure, and composition of the mixture is carried out. It is observed that increasing...
Application of Cardo-type polyimide (PI) and polyphenylene oxide (PPO) hollow fiber membranes in two-stage membrane systems for CO2/CH4 separation
, Article Journal of Membrane Science ; Volume 324, Issue 1-2 , 2008 , Pages 85-94 ; 03767388 (ISSN) ; Soltanieh, M ; Matsuura, T ; Tabe Mohammadi, A ; Sadeghi, M ; Sharif University of Technology
Elsevier B.V
2008
Abstract
In this study, a two-stage membrane system for the separation of CH4/CO2 was designed based on a series of laboratory-scale experiments obtained using two types of commercial hollow fiber membranes including polyphenylene oxide (PPO) and Cardo-type polyimide (PI). The former showed high permeability and low to moderate selectivity, while the latter exhibited high selectivity and moderate permeability. In this design, the permeate from the first stage - rich in CO2 but containing considerable amount of methane - is fed into the second stage to recover its methane content. The performances of double- and single-stage system designs were compared in terms of methane loss (the ratio of methane...
Solubility of CO2 and H2S in the ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate
, Article Journal of Natural Gas Science and Engineering ; Volume 30 , Volume 30 , 2016 , Pages 583-591 ; 18755100 (ISSN) ; Jalili, A. H ; Ghotbi, C ; Rashtchian, D ; Sharif University of Technology
Elsevier
2016
Abstract
The solubility of carbon dioxide and hydrogen sulfide gases in the ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([C2mim][OTf]) was measured at temperatures from (303.15-353.15) K and pressures up to about 3.0 MPa. The Henry's law constants were determined from the new experimental data, which in turn were used to derive the change of some thermodynamic functions of dissolution of the gases in that particular ionic liquid. The new experimental data were correlated by a combination of the extended Henry's law and Pitzer's model for the excess Gibbs energy. The average relative percent deviation (ARD%) of correlated molality values from experimental data are within...