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    Desalination through sweeping gas membrane distillation alternative

    , Article CHISA 2012 - 20th International Congress of Chemical and Process Engineering and PRES 2012 - 15th Conference PRES ; 2012 Bastani, D ; Kargari, A ; Shirazi, M. M. A ; Fatehi, L ; Soleimani, M ; Sharif University of Technology
    Sweeping gas membrane distillation process was studied using flat sheet hydrophobic PTFE membrane. The effects of operating parameters, including feed temperature, feed flow rate, sweeping gas flow rate, and feed concentration on the permeate flux, were determined. The feed temperature significantly influenced the permeate flux. Increasing the feed temperature increased the permeate flux. The increase of feed concentration caused to reduce the permeate flux due to the increase of concentration polarization effect and reduction of vapor pressure difference. Sweeping gas flow rate led to increase the permeate flux due to reduction of vapor pressure in the permeate side. Higher air flow rate... 

    Study on commercial membranes and sweeping gas membrane distillation for concentrating of glucose syrup

    , Article Journal of Membrane Science and Research ; Volume 6, Issue 1 , 2020 , Pages 47-57 Shirazi, M. M. A ; Kargari, A ; Bastani, D ; Soleimani, M ; Fatehi, L ; Sharif University of Technology
    Amirkabir University of Technology - Membrane Processes Research Laboratory  2020
    In this work, sweeping gas membrane distillation (SGMD) process was used for concentrating of glucose syrup. The main questions in this work include: is SGMD process practical for concentrating of glucose solution prior the fermentation step in bioethanol process?. and are the commercially available hydrophobic membranes sufficient enough to develop the SGMD process in pilot scale for this issue?. To answer these questions, SGMD process was performed using three commercial membranes made of PP, PVDF and PTFE. All membranes characterized using scanning electron and atomic force microscopes for their morphological and topographical features. Important operating parameters including feed... 

    Experimental Investigation of Effective Parameters on Lead Ion Removal by Nanofiltration

    , M.Sc. Thesis Sharif University of Technology Mehdipour Zareh, Saber (Author) ; Kariminia, Hamidreza (Supervisor) ; Vatanpoor, Vahid ($item.subfieldsMap.e)
    In this study, the effects of parameters such as operation pressure, concentration of Pb2+ ion, nature of associated anion, pH of initial feed and composition of feed was investigated by commercial polyamide nanofilter membrane. One-salt solution nanofiltration experiments was performed by using Pb(NO3)2, PbCl2 and PbSO4 and the binary-salt solution experiments was conducted by using Cu(NO3)2, Cd(NO3)2, Zn(NO3)2, NaNO3 and NH4NO3 together with Pb(NO3)2. The binary-salt experiments in presence of monovalent and divalent cations (together with Pb2+) were performed successively. At first the surface charge of membrane in contact with 1mM KCl solution at pH range of 3-7 was measured. The pH of... 

    Chemical Engineering- Transport Phenomena and Separation Processes

    , M.Sc. Thesis Sharif University of Technology Reyhani, Amin (Author) ; Safekordi, Ali Akbar (Supervisor) ; Hemmati, Mahmoud (Supervisor)
    In this study, experimental results of Ahvaz produced water treatment obtained in ultrafiltration process using a polymeric membrane formed from Polyacrylonitrile (PAN) with 0.2 µm poreshave been reported. In this process the effects of different factors including transmembrane pressure (TMP), cross flow velocity (CFV) and feed temperature on permeate flux, membrane fouling resistance and TOC rejection was investigated. The results show that optimum conditionswere found in the range of TMP: 1.5-3 bar, CFV: 1-1.5 m/s and operating temperature 40°C.Results show that under optimum conditions the final permeate flux for produced water of Asmari outlet of Skimmer unit was 30 L/m2.h, and the... 

    Response surface methodology for modeling and optimizing the treatment of synthetic starchy wastewater using hydrophilic PES membrane

    , Article Desalination and Water Treatment ; Volume 51, Issue 37-39 , 2013 , Pages 7036-7047 ; 19443994 (ISSN) Hedayati Moghaddam, A ; Shayegan, J ; Sargolzaei, J ; Bahadori, T ; Sharif University of Technology
    In this work, the process of starch removal from starchy wastewater using a hydrophilic polyethersulfone membrane was investigated. The pore size of the membrane was 0.65 μm and the pattern of stream in plate and frame handmade membrane module was cross-flow. To design the layout of the experiments, response surface methodology was applied. The performance of the filtration process was evaluated by calculating the (chemical oxygen demand) COD removal percentage (rejection factor) and permeate flux. In this study, five operative parameters were investigated, including trans-membrane pressure, flow rate and temperature of feed, pH, and the COD concentration of starch wastewater. Two models... 

    Pervaporation of toluene and iso-octane through poly(vinyl alcohol)/graphene oxide nanoplate mixed matrix membranes: Comparison of crosslinked and noncrosslinked membranes

    , Article Journal of Applied Polymer Science ; Volume 135, Issue 7 , 2018 ; 00218995 (ISSN) Khazaei, A ; Mohebbi, V ; Behbahani, R. M ; Ramazani S. A., A ; Sharif University of Technology
    John Wiley and Sons Inc  2018
    Removal of aromatic compounds from fuel is an essential requirement in new environmental policies. In the present study, poly(vinyl alcohol)/graphene oxide (GO) mixed matrix membranes were prepared and applied to the separation of toluene from iso-octane by pervaporation, considering the similarity and interaction between graphene and aromatics. The effects of crosslinking and GO content on separation efficiency have been investigated in detail. Owing to the high affinity of GO with toluene through s and π bonds, the selectivity of the membranes was increased by incorporating a low amount of GO. The results also indicated that noncrosslinked membranes have higher selectivity and permeation... 

    Experimental investigation, modeling and optimization of membrane separation using artificial neural network and multi-objective optimization using genetic algorithm

    , Article Chemical Engineering Research and Design ; Volume 91, Issue 5 , 2013 , Pages 883-903 ; 02638762 (ISSN) Soleimani, R ; Shoushtari, N. A ; Mirza, B ; Salahi, A ; Sharif University of Technology
    In this work, treatment of oily wastewaters with commercial polyacrylonitrile (PAN) ultrafiltration (UF) membranes was investigated. In order to do these experiments, the outlet wastewater of the API (American Petroleum Institute) unit of Tehran refinery, is used as the feed. The purpose of this paper was to predict the permeation flux and fouling resistance, by applying artificial neural networks (ANNs), and then to optimize the operating conditions in separation of oil from industrial oily wastewaters, including trans-membrane pressure (TMP), cross-flow velocity (CFV), feed temperature and pH, so that a maximum permeation flux accompanied by a minimum fouling resistance, was acquired by... 

    Production of drinking water from seawater using membrane distillation (MD) alternative: Direct contact MD and sweeping gas MD approaches

    , Article Desalination and Water Treatment ; Vol. 52, issue. 13-15 , Apr , 2014 , p. 2372-2381 Shirazi, M. M. A ; Kargari, A ; Bastani, D ; Fatehi, L ; Sharif University of Technology
    In this work, two-membrane distillation (MD) modes, direct contact MD, and sweeping gas MD were investigated for synthesized and real (Persian Gulf) seawater desalination. A commercial PTFE membrane with 0.22 μm pore size was characterized (using atomic force microscopy and scanning electron microscopy) and was used for experiments. A multipurpose plate and frame MD module was used for desalination experiments. The effects of various operating conditions and MD module design, as well as feed type on the permeation flux have been studied. The feed temperature was found to be the most effective operating parameter. The flow rate in both sides of the MD module was found to be effective;... 

    Comparison of microstructure and hydrogen permeability of perovskite type ACe0.9Y0.1O3-δ (A is Sr, Ba, La, and BaSr) membranes

    , Article International Journal of Hydrogen Energy ; Volume 40, Issue 20 , 2015 , Pages 6559-6565 ; 03603199 (ISSN) Heidari, M ; Safekordi, A ; Zamaniyan, A ; Ganji Babakhani, E ; Amanipour, M ; Sharif University of Technology
    Hydrogen permeation through ACe0.9Y0.1O3-δ (A = Sr, Ba, La, and BaSr) perovskite-type membranes was studied at high temperatures. X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were used to characterize phase structure and phase stability of the membrane. The XRD results showed the formation of a single phase of perovskite structure with configuration orthorhombic for BCY and BSCY membranes. Based on the TGA results, it was found that the phase stability increases in the order of LCY < SCY < BCY < BSCY. The microstructure examinations of the synthesized membranes studied by scanning electron microscopy (SEM) showed the formation of a dense-like... 

    Comparison of oxygen permeation through some perovskite membranes synthesized with EDTNAD

    , Article Reaction Kinetics, Mechanisms and Catalysis ; Volume 100, Issue 2 , August , 2010 , Pages 459-469 ; 18785190 (ISSN) Taheri, Z ; Nazari, K ; Seyed Matin, N ; Safekordi, A. A ; Ghanbari, B ; Zarrinpashne, S ; Ahmadi, R ; Sharif University of Technology
    Three dense membranes of types SrCo0.8Fe0.2O 3-δ (SCF(82)), La0.6Sr0.4Co 0.8Fe0.2O3-δ (LSCF(6482)) and La 0.8Sr0.2Co0.6Fe0.4O 3-δ (LSCF(8264)) perovskites were prepared by complexation applying a chelating agent, ethylene diamine N,N,N′,N′-tetra-N- acetyl-diamine (EDTNAD). The oxygen permeation flux through the perovskite membranes was measured as a function of temperature within 1,073-1,223 K as well as the oxygen partial pressure of 0.1-1.0 bar. The oxygen permeation fluxes for the membranes, SCF(82), LSCF(6482), LSCF(8264) with the thickness of 0.85 mm were observed as 9.2×10-7 (mol/cm2 s), 1.7×10-7 (mol/cm2 s), and 1.0×10-7 (mol/cm2 s) in these cases at 1,153 K. The results indicated the... 

    Poly(vinyl alcohol)/graphene oxide mixed matrix membranes for pervaporation of toluene and isooctane

    , Article Polymer - Plastics Technology and Engineering ; Volume 56, Issue 12 , 2017 , Pages 1286-1294 ; 03602559 (ISSN) Khazaei, A ; Mohebbi, V ; Behbahani, R. M ; Ahmad Ramazani, S. A ; Sharif University of Technology
    Poly(vinyl alcohol)/graphene oxide mixed matrix membranes have been prepared and applied for the pervaporation of isooctane (aliphatic) and toluene (aromatic) mixtures. Characteristics of the membranes such as crystallinity, morphology, and swelling have been investigated, and the results have been used to describe pervaporation performance. Experimental tests evidenced that incorporation of low content of graphene oxide nanoplates (0.5 wt%) in poly(vinyl alcohol) increases affinity of the membrane to aromatics by S and π bonds and selectivity increase to about four times. Moreover, interaction of graphene oxide with toluene results in increasing of swelling and decreasing of permeation... 

    Effect of Sintering Temperature on Microstructure and Hydrogen Permeation Properties of Perovskite Membrane

    , Article Journal of Materials Science and Technology ; Volume 29, Issue 2 , 2013 , Pages 137-141 ; 10050302 (ISSN) Heidari, M ; Zamaniyan, A ; SafeKordi, A ; Ganji Babakhani, E ; Amanipour, M ; Sharif University of Technology
    The BaCe0.9Y0.1O3-δ (BCY) perovskite membrane was successfully synthesized by liquid citrate method. The phase structure of the powder was characterized by X-ray diffraction (XRD). Scanning electron microscopy (SEM) was used to characterize microstructures of the membrane sintered under various conditions. Sintering temperatures and dwell time during sintering influence the final microstructure of the ceramic. Results showed that increasing sintering temperature resulted in a dense membrane with clear grains. An increase of dwell time was favorable to produce membranes with larger grains in the sintered ceramics. A density of 5.87 g/cm3 was reached for the membrane after sintering at 1200 °C... 

    Modeling of transient permeate flux decline during crossflow microfiltration of non-alcoholic beer with consideration of particle size distribution

    , Article Journal of Membrane Science ; Volume 411-412 , September , 2012 , Pages 13-21 ; 03767388 (ISSN) Kazemi, M. A ; Soltanieh, M ; Yazdanshenas, M ; Sharif University of Technology
    Crossflow microfiltration of non-alcoholic beer is investigated numerically and it has been verified by experimental data. Due to the presence of particles with different sizes in feed suspension, a modified combination of three mechanisms of particle back-diffusion is developed to predict particle deposition and cake layer buildup during the process. The simulation results show that smaller particles (about 1μm) are the main contributor to the cake layer due to a minimum in back transport and are the main reason of the flux decline. On the other hand, larger particles (a p>20μm) are swept away along the membrane during the filtration process and move toward the membrane exit due to the... 

    Treatment of welding electrode manufacturing plant wastewater using coagulation/flocculationnanofiltration as a hybrid process

    , Article Brazilian Journal of Chemical Engineering ; Volume 28, Issue 1 , Mar , 2011 , Pages 73-79 ; 01046632 (ISSN) Golestani, H. A ; Mousavi, M ; Borghei, M ; Sharif University of Technology
    High water consumption and water scarcity make industrial wastewater reuse necessary, especially in those industries characterized by polluted effluents such as welding electrode manufacturing industries. The present paper investigates the coupling of coagulation-flocculation with nanofiltration (NF) to recycle water and reuse it in the process. First, the effect of different concentrations of a mixture of alum (Al2(SO4) 3.18H2O) and ferric chloride (FeCl3) on the pretreatment process was closely studied. Then the NF process was applied for complementary treatment. The NF results show that, by increasing both flow rate and transmembrane pressure (TMP), permeate flux is increased. The NF... 

    Investigation of membrane fouling in cross flow microfiltration of non-alcoholic beer and modeling of tubular membrane flow

    , Article Desalination ; Volume 251, Issue 1-3 , 2010 , Pages 20-28 ; 00119164 (ISSN) Hajipour, M ; Soltanieh, M ; Yazdanshenas, M ; Sharif University of Technology
    In the present work, numerical simulation of cross flow microfiltration of non-alcoholic beer in a tubular membrane has been studied theoretically and verified experimentally. Finite element method was used as a powerful tool for simulation. The feed stream, which flows mainly tangentially to the porous membrane surface, is modeled by the Navier-Stokes equations whereas the porous wall conditions are described by the Darcy equation that relates the pressure gradient within a flow stream to the flow rate through the permeable wall. A new model that considers transient behavior of the membrane due to fouling was used to estimate the permeate flux reduction. A pilot-scale cross flow membrane... 

    Effective factors in the treatment of kerosene-water emulsion by using UF membranes

    , Article Journal of Hazardous Materials ; Volume 161, Issue 2-3 , 2009 , Pages 1216-1224 ; 03043894 (ISSN) Rezvanpour, A ; Roostaazad, R ; Hesampour, M ; Nyström, M ; Ghotbi, C ; Sharif University of Technology
    The effects of different parameters including membrane type (regenerated cellulose and polysulphone), transmembrane pressure (TMP), the content of oil in the feed, the flow velocity of the feed and pH on the ultrafiltration of an emulsion of kerosene in water were studied. It was found that the important factors affecting ultrafiltration were, in order, membrane type, pressure and oil concentration. The greatest flux at the optimum conditions here of 3 bar, an oil content of 3% (v/v) and with membrane type C30F was predicted as 108 L/(m2 h) that was within the range of the confidence limit of the measured value of 106 L/(m2 h). The normalised FTIR results of the virgin cellulosic membranes...