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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...
Thin film UV-curable acrylate polyurethane/MOF mixed matrix membranes for CO2 separation
, Article 18th European Conference on Composite Materials, ECCM 2018, 24 June 2018 through 28 June 2018 ; 2020 ; Molavi, H ; Mousavi, S. A ; Adamant Composites Ltd.; Hellenic Aerospace Industry S.A; JEC Group; Materials Today; Photron; Shimadzu Europa GmbH ; Sharif University of Technology
Applied Mechanics Laboratory
2020
Abstract
The major obstacles in gas separation by mixed-matrix composite membranes (MMCMs) are poor dispersion and poor affinity between polymers and fillers. The present study demonstrates that these challenges can be overcome appropriately by utilizing a series of synthesized MMCMs. MMCMs were prepared with UV-curable polyurethane acrylate and UiO-66 as selective layer and polyester/polysulfone (PS/PSF) as support layer. The physical properties of prepared MMCMs were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). Microscopic analysis by FESEM revealed that desirable nanoscale dispersion of UiO-66,...
Structural and transport properties of polydimethylsiloxane based polyurethane/silica particles mixed matrix membranes for gas separation
, Article Korean Journal of Chemical Engineering ; Volume 31, Issue 5 , 2014 , Pages 841-848 ; ISSN: 02561115 ; Ghalei, B ; Fardi, M ; Esmaeeli, M ; Vakili, E ; Sharif University of Technology
Abstract
Mixed matrix membranes of synthesized polyurethane (PU) based on toluene diisocyanate (TDI), polydimethylsiloxane (PDMS) and polytetramethylene glycol (PTMG) with polyvinyl alcohol based polar silica particles were prepared by solution casting technique. The homogeneity and thermal properties of the prepared PDMS-PU/silica membranes were characterized using scanning electron microscope (SEM), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The SEM micrographs confirmed the distribution of silica particles in the polymer matrix without agglomerations. Gas permeation properties of membranes with different silica contents were studied for pure CO2, CH4, O2, He...
Novel surface modifying macromolecules (SMMs) blended polysulfone gas separation membranes by phase inversion technique
, Article Journal of Applied Polymer Science ; Volume 124, Issue 3 , 2012 , Pages 2287-2299 ; 00218995 (ISSN) ; Rana, D ; Matsuura, T ; Soltanieh, M ; Tabe, S ; Sharif University of Technology
2012
Abstract
In this article an attempt was made to fabricate defect-free asymmetric polysulfone (PSf) membranes for the separation of oxygen and nitrogen. The approach is based on the enhanced delayed demixing by blending surface modifying macromolecules (SMMs) in the casting solution and by immersing the cast film in isopropanol for a certain period before it is immersed in water. Different SMMs, including hydrophobic and charged SMMs, were synthesized, characterized, and blended to the host PSf. It was found that the charged SMM could indeed contribute to the removal of defective pores from the skin layer and enhancement of oxygen/nitrogen selectivity. The experimental results were further interpreted...
Influence of novel surface modifying macromolecules and coagulation media on the gas permeation properties of different polymeric gas separation membranes
, Article Journal of Applied Polymer Science ; Volume 124, Issue 3 , 2012 , Pages 2300-2310 ; 00218995 (ISSN) ; Rana, D ; Matsuura, T ; Soltanieh, M ; Tabe, S ; Sharif University of Technology
2012
Abstract
Integrally skinned asymmetric membranes for the separation of O 2 and N 2 were fabricated by the phase inversion technique from polysulfone, polyetherimide, and polyimide. Two types of surface modifying macromolecules (SMMs) including hydrophilic SMM (LSMM) and charged SMM (cSMM) were synthesized and blended with the casting solution to modify the membrane surface. The cast film was then immersed in the first coagulant alcohol (methanol, ethanol, or isopropanol) for a predetermined period, before being immersed in the second coagulant (water). The SMMs used in these experiments were laboratory synthesized by the two-step process of polyurethane prepolymer synthesis and end capping, before...
Plasticization effect on performance of polyphenylene oxide hollow fiber membrane at high concentrations of hydrogen sulfide
, Article 19th International Congress of Chemical and Process Engineering, CHISA 2010 and 7th European Congress of Chemical Engineering, ECCE-7, 28 August 2010 through 1 September 2010 ; 2010 ; Niknejad, S. M. S ; Soltanieh, M ; Sharif University of Technology
Abstract
Natural gas contains several impurities, e.g., CO 2 and H 2S, which have undesirable effects on the performance of the glassy polymeric membranes. The plasticization effect of H 2S at high concentrations on the gas separation performance of polyphenylene oxide hollow fiber membrane has been studied at different compositions of H 2S and feed pressures. The existence of high concentrations of H 2S in CH 4 feed mixture, which is present in many natural gas sources in Iran, enhances plasticization. For a H 2S/CH 4 mixture containing 5008 ppm H 2S at ≈ 75 psig, the H 2S permeance reduces by > 45% from its initial value. H 2S acts as a plasticizer in H 2S/CH 4 membrane separation at elevated...
Study of the solubility of CO2, H2S and their mixture in the ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate: Experimental and modelling
, Article Journal of Chemical Thermodynamics ; Volume 65 , 2013 , Pages 220-232 ; 00219614 (ISSN) ; Ghotbi, C ; Taghikhani, V ; Jalili, A. H ; Mehdizadeh, A ; Sharif University of Technology
2013
Abstract
New experimental results are presented for the solubility of carbon dioxide, hydrogen sulfide in the ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate ([C8mim][PF6]) at temperatures range from (303.15 to 353.15) K and pressures up to about 2 MPa. The solubility of the mixture of CO2/H2S in [C8mim][PF6] under various feed compositions were also measured at temperatures of (303.15, 323.15 and 343.15) K and the pressure up to 1 MPa. The solubility of carbon dioxide and hydrogen sulfide increased with increasing pressure and decreased with increasing temperature and the solubility of H2S is about three times that of CO2 in the particular ionic liquid studied. The measured data were...
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...
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...
Improvement in CO2/H2 separation by fabrication of poly(ether-b-amide6)/glycerol triacetate gel membranes
, Article Journal of Membrane Science ; Vol. 469, issue , 2014 , pp. 43-58 ; ISSN: 03767388 ; Soltanieh, M ; Mousavi, S. A ; Ghadimi, A ; Sharif University of Technology
Abstract
The purpose of this study is to investigate separation performance of poly(ether-b-amide6) (Pebax1657)/glycerol triacetate (GTA) gel membranes for CO2 removal from H2, N2 and CH4. GTA as a low molecular weight and highly CO2-phill compound was added to membrane structure at various weight fractions, 20%, 40%, 60% and 80% of Pebax, to fabricate a new high solubility selective membrane with improved performance. Permeation of pure gases was studied at different temperatures from 25 to 65°C and pressures from 4 to 24bar and ideal selectivities were calculated. Results indicated enhancement in permeation for all tested gases. For example, at a pressure of 4bar and a temperature of 25°C, membrane...
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...
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...
The effect of water vapor on the performance of commercial polyphenylene oxide and Cardo-type polyimide hollow fiber membranes in CO2/CH4 separation applications
, Article Journal of Membrane Science ; Volume 285, Issue 1-2 , 2006 , Pages 265-271 ; 03767388 (ISSN) ; Soltanieh, M ; Matsuura, T ; Tabe Mohammadi, A ; Khulbe, K. C ; Sharif University of Technology
2006
Abstract
The effects of water vapor on CO2/CH4 separation using commercially available poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) and Cardo-type polyimide hollow fiber membranes were investigated. Pure methane and CO2/CH4 mixture permeation experiments were carried out in the absence and presence of water vapor (60% RH). Pure methane permeance decreased in the presence of water vapor for both membrane types. The decrease was 28% for hydrophilic Cardo-type polyimide and 6% for hydrophobic PPO membranes. The decline in the permeance was also observed for CO2/CH4 mixture separation through both membranes. However, selectivities of the two membranes were affected differently by water vapor. The...
Gas permeation properties of commercial polyphenylene oxide and Cardo-type polyimide hollow fiber membranes
, Article Separation and Purification Technology ; Volume 51, Issue 3 , 2006 , Pages 359-366 ; 13835866 (ISSN) ; Soltanieh, M ; Matsuura, T ; Tabe Mohammadi, A ; Feng, C ; Sharif University of Technology
2006
Abstract
Gas separation properties of commercially available polyphenylene oxide (PPO) and Cardo-type polyimide (PI) hollow fiber membranes were investigated by CO2/CH4 and O2/N2 separation experiments. The pure gas permeation and the mixed gas separation experiments indicated that the two hollow fiber membranes were suitable candidates for O2/N2 and CO2/CH4 separations. Average O2/N2 permselectivities of 3.9 and 5.7 for PPO and PI hollow fibers, respectively, average CO2/CH4 permselectivities of 16.4 and 36.0 for PPO and PI hollow fibers, respectively, CO2 permeances of 210 and 110 GPU at 100 psig for PPO and PI hollow fibers, and O2 permeances of 40 GPU and 15 GPU for PPO and PI hollow fibers were...
Mathematical modeling and simulation of hollow fiber membranes for separation of gas mixtures: Case study with separation of H 2S/CH 4 by polyphenylene oxide (PPO) hollow fiber module
, Article 19th International Congress of Chemical and Process Engineering, CHISA 2010 and 7th European Congress of Chemical Engineering, ECCE-7, Prague, 28 August 2010 through 1 September 2010 ; 2010 ; Savoji, H ; Soltanieh, M ; Sharif University of Technology
2010
Abstract
A mathematical model has been developed that is based the dual sorption in the dense layer and pore flow in the porous layer. In the porous layer a resistance model is applied where four mechanisms, i.e., Knudsen, Viscous, Slip, and Surface flows, are superimposed. Steady-state, constant pressure along the membrane and constant physical properties are assumed. Its application to the separation of H 2S/CH 4 gas mixtures as a sour gas in natural gas sweetening by using a PPO hollow fiber module is put forward. The Quasi Newton method is used to determine the parameters of membrane transport model for the case of H 2S/CH 4 separation. The H 2S and CH 4 permeances increased by increasing the...
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...
Study of gas separation properties of ethylene vinyl acetate (EVA) copolymer membranes prepared via phase inversion method
, Article Separation and Purification Technology ; Volume 62, Issue 3 , 22 September , 2008 , Pages 642-647 ; 13835866 (ISSN) ; Sadeghi, M ; Motamed Hashemi, M. M. Y ; Pourafshari Chenar, M ; Roosta Azad, R ; Sadeghi, M ; Sharif University of Technology
2008
Abstract
The gas separation properties of ethylene vinyl acetate (EVA) membranes containing 18 and 28 wt% of vinyl acetate (VA) were investigated in this study. The effects of membrane preparation conditions, such as thermal and thermal/wet phase inversion, and the type of solvent on the gas separation properties of EVA membranes were investigated. The permeation of pure O2, N2, CH4, and CO2 gases at different feed pressures ranging from 2 to 11 bar were examined. The results indicated that the CO2 permeability was evidently higher than those of the other gases. Furthermore, the solubility mechanism was found to be the dominant mechanism for permeation of gases through EVA membranes. Moreover, the...
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...
Mixed-matrix composite membranes based on uio-66-derived MOFs for CO 2 separation
, Article ACS Applied Materials and Interfaces ; Volume 11, Issue 9 , 2019 , Pages 9448-9461 ; 19448244 (ISSN) ; Shojaei, A ; Sharif University of Technology
American Chemical Society
2019
Abstract
We demonstrated a novel mixed-matrix composite membrane (MMCM) based on acrylated polyurethane (APU) and UiO-66 nanoparticles to separate CO 2 /N 2 mixture. UiO-66 and functionalized UiO-66 including NH 2 -UiO-66 and glycidyl methacrylate (GMA)-UiO-66 were loaded into APU/2-hydroxyethyl methacrylate (APUH) matrix at variable concentrations between 3 and 30 wt %. APUH/GMA-UiO-66 MMCMs exhibited strong adhesion with a support layer of polyester/polysulfone, which was not deteriorated after immersion in water for a long time (20 days). Incorporation of UiO-66 and its functionalized forms increased simultaneously permeability and CO 2 /N 2 selectivity, which were indeed superior in comparison...
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...