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    Studying the Mechanistic Behavior of Heavy Oil Displacement Using a Group of Alkalis and Surfactant Mixtures

    , Article Chemical Engineering Communications ; Vol. 202, issue. 3 , May , 2015 , p. 366-374 ; ISSN: 00986445 Dehghan, A. A ; Jadaly, A ; Masihi, M ; Ayatollahi, S ; Sharif University of Technology
    Abstract
    In this study, a mixture-based sulfonate-based surfactant with a novel formula capable of functioning in real oil reservoir conditions was prepared and some microscopic parameters, like its compatibility state, emulsion behavior, interfacial tension, and temperature dependency in the presence of a heavy oil sample, and two of the most popular alkalis were analyzed; then the results were compared with those of a commercial sulfate-based surfactant. The designed surfactant provided an optimum three-phase region in relatively high salinity media; however, its optimum value decreased when adding any alkaline materials; this trend was reversed for the solutions made with the sulfate-based... 

    Studying the mechanistic behavior of heavy oil displacement using a group of alkalis and surfactant mixtures

    , Article Chemical Engineering Communications ; Volume 202, Issue 3 , 2015 , Pages 366-374 ; 00986445 (ISSN) Dehghan, A. A ; Jadaly, A ; Masihi, M ; Ayatollahi, S ; Sharif University of Technology
    Taylor and Francis Ltd  2015
    Abstract
    In this study, a mixture-based sulfonate-based surfactant with a novel formula capable of functioning in real oil reservoir conditions was prepared and some microscopic parameters, like its compatibility state, emulsion behavior, interfacial tension, and temperature dependency in the presence of a heavy oil sample, and two of the most popular alkalis were analyzed; then the results were compared with those of a commercial sulfate-based surfactant. The designed surfactant provided an optimum three-phase region in relatively high salinity media; however, its optimum value decreased when adding any alkaline materials; this trend was reversed for the solutions made with the sulfate-based... 

    Colloidal gold nanoparticles: an unexpected catalytic activity in aqueous phase with dioxygen

    , Article catalysis letters ; Volume 144, Issue 7 , July , 2014 , pp. 1219-1222 ; 1572-879X Salari, H. (Hadi) ; Robatjazi, H. (Hossein) ; Hormozi-Nezhad, M. (Mohammad Reza) ; Padervand, M. (Mohsen) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
    Abstract
    Selective oxidations of alkenes were investigated using molecular oxygen in aqueous solution under mild conditions. Colloidal gold nanoparticles are particularly versatile catalysts for oxidation reaction with exceptionally high efficiency and significant selectivity. Gold nanorods (Au NRs) exhibited a slightly enhanced activity compare to gold nanospheres  

    A pore-level investigation of surfactant-crude oil displacements behavior in fractured porous media using one-quarter five spot micromodels

    , Article Energy Sources, Part A: Recovery, Utilization and Environmental Effects ; Vol. 36, issue. 7 , April , 2014 , pp. 727-737 ; ISSN: 15567036 Kianinejad, A ; Rashtchian, D ; Ghazanfari, M. H ; Kharrat, R ; Sharif University of Technology
    Abstract
    Despite numerous studies, there is a lack of fundamental understanding about the displacement behavior of surfactant-crude oil systems under the influence of different fractures' geometrical properties in five-spot systems. In this work, a series of flow visualization experiments were carried out on one-quarter five spot glass micromodels at various fractures' geometrical properties, such as fracture density and fracture continuity, under oil-wet condition. The influences of injection of Linear Alkyl Benzene Sulfonate and Sodium Dodecyl Sulfate surfactants as well as the effect of fracture geometrical parameters, on macroscopic and microscopic displacement behavior have been investigated.... 

    The impact of surfactants on wettability change and level of water imbibition in relation to EOR in carbonate reservoirs

    , Article Petroleum Science and Technology ; Volume 31, Issue 20 , 2013 , Pages 2098-2109 ; 10916466 (ISSN) Zangeneh Var, A ; Bastani, D ; Badakhshan, A ; Sharif University of Technology
    2013

    Recovery of surfactants from oil in water emulsions by electroflotation

    , Article 8th World Congress of Chemical Engineering: Incorporating the 59th Canadian Chemical Engineering Conference and the 24th Interamerican Congress of Chemical Engineering, 23 August 2009 through 27 August 2009, Montreal, QC ; 2009 Biria, D ; Mansouri, M ; Maghsoudi, E ; Roostaazad, R ; Dadafarin, H ; Sharif University of Technology
    Abstract
    An electroflotation technique was utilized to reclaim the surfactant molecules from oil-in-water emulsions. A two-staged separation mechanism was suggested to describe the process. The surfactant recovery efficiencies were higher than 70% after 30 min treatment. The method could be an effective process in recycling surfactants from the emulsions existing in industrial wastes. This is an abstract of a paper presented at the 8th World Congress of Chemical Engineering (Montreal, Quebec, Canada 8/23-27/2009)  

    CFD simulation of bubble in flow field: Investigation of dynamic interfacial behaviour in presence of surfactant molecules

    , Article Colloids and Interface Science Communications ; Volume 27 , 2018 , Pages 1-10 ; 22150382 (ISSN) Bastani, D ; Fayzi, P ; Lotfi, M ; Arzideh, S. M ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    This work presents the results of numerical simulation of liquid flow on a static bubble. Velocity and surfactant concentration profiles of the liquid around a bubble exposed in flow field were estimated via unsteady CFD solution. Governing equations are the Navier-Stokes and conservation of mass in the liquid bulk and at the interface. Resulted profiles of surfactant concentration and velocity in the liquid bulk are used to determine the dynamic surface tension data via two adsorption isotherms of Langmuir and Frumkin. Data of dynamic surface tension were validated via experimental data of “bubble in flow field” protocol. Surface concentrations of surfactants were also numerically... 

    Synergistic effect of like and opposite charged nanoparticle and surfactant on foam stability and mobility in the absence and presence of hydrocarbon: a comparative study

    , Article Journal of Petroleum Science and Engineering ; Volume 166 , July , 2018 , Pages 433-444 ; 09204105 (ISSN) Veyskarami, M ; Ghazanfari, M. H ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    The aim of this study is to compare the synergistic impact of like and opposite-charged nanoparticle and surfactant systems on enhancing stability and mobility of foam in the absence and presence of oil which is not sufficiently discussed in the available literature. Stability of nanoparticle dispersion is examined at various levels of pH when nanoparticle and surfactant are in like and opposite-charged conditions. In situ modification of silica nanoparticle by opposite-charged surfactant is analyzed. Static stability tests as well as Hele–Shaw cell are employed to understand how nanoparticle and surfactant charges may control the stability and mobility of foam when oil is present/absent.... 

    Influence of β-lactoglobulin and its surfactant mixtures on velocity of the rising bubbles

    , Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Vol. 460 , October , 2014 , pp. 361-368 ; ISSN: 09277757 Ulaganathan, V ; Krzan, M ; Lotfi, M ; Dukhin, S. S ; Kovalchuk, V. I ; Javadi, A ; Gunes, D. Z ; Gehin-Delval, C ; Malysa, K ; Miller, R ; Sharif University of Technology
    Abstract
    The rising velocity of air bubbles in surfactant solutions is a sensitive measure for the formation of a dynamic adsorption layer (DAL) at the bubble surface. Due to a certain surface coverage by adsorbed species the bubble surface starts to become immobilized and the rising velocity is retarded. There is a large difference in the retardation effect in presence of the protein β-lactoglobulin (BLG) alone and its mixed solutions with surfactants. In presence of added surfactants BLG forms complexes, which adsorb and retard the bubble rising velocity according to their respective surface activity and adsorption kinetics. While the nonionic surfactant C12DMPO does not show significant increase... 

    Experimental study of nanoparticle-surfactant-stabilized CO2 foam: Stability and mobility control

    , Article Chemical Engineering Research and Design ; Volume 111 , 2016 , Pages 449-460 ; 02638762 (ISSN) Farhadi, H ; Riahi, S ; Ayatollahi, S ; Ahmadi, H ; Sharif University of Technology
    Institution of Chemical Engineers  2016
    Abstract
    CO2 injection has proved to be the most common and efficient enhanced oil recovery techniques which leads to more residual oil recovery. Unfavorable sweep efficiency which results in fingering propagation and causes early gas breakthrough is the most challenging issue of gas flooding process. The aim of this work is to study foam stability and analyze the mobility of CO2 foam stabilized by mixture of raw silica nanoparticles and ethyl hexadecyl dimethyl ammonium bromide (cationic surfactant). The result is obtained through both dynamic and static techniques using a new adsorption index.NPS-stabilized foams are generated using Ross-Miles method. A novel index for the adsorption of surfactant... 

    Investigating the synergic effects of chemical surfactant (SDBS) and biosurfactant produced by bacterium (Enterobacter cloacae) on IFT reduction and wettability alteration during MEOR process

    , Article Journal of Molecular Liquids ; Volume 256 , 2018 , Pages 277-285 ; 01677322 (ISSN) Hajibagheri, F ; Hashemi, A ; Lashkarbolooki, M ; Ayatollahi, S ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    In the current study, a novel approach which takes into account the effectiveness of both convectional surfactants and biosurfactants was investigated. The biosurfactant produced by Enterobacter cloacae strain was utilized concomitant with conventional surfactant (sodium dodecyl benzene sulfonate (SDBS)) to evaluate its capability to reduce the SDBS adsorption on rock surface (biosurfactant acts as sacrificial agent) or synergistically enhance the effectiveness of the SDBS. In this regard, the wettability alteration and interfacial tension (IFT) measurements and calculation of spreading coefficient were performed considering two different scenarios. In the first scenario, SDBS was added to... 

    Experimental Study of Partitioning of Lysozyme Enzyme in Aqueous Two-Phase Systems based on Surfactants

    , M.Sc. Thesis Sharif University of Technology Barjasteh, Mahdi (Author) ; Bastani, Dariush (Supervisor) ; Vosoughi, Manochehr (Supervisor)
    Abstract
    In this study, aqueous two-phase systems (ATPS) containing Tween 20 as a biocompatible nonionic surfactant and three different salts (NH4HPO4, NH4CH3COO and Mg(CH3COO)2 ) were prepared and their extractive potential for Lysozyme enzyme was evaluated. These systems have surfactant-rich top phase and salt-rich bottom phase. Phase equilibrium diagrams at 23 ° C were obtained by using the cloud point method and the results were successfully fitted to the Merchuk correlation and their trends were correlated with the effective excluded volume (EEV) parameter. Afterward, the partitioning behavior of the lysozyme and its extraction efficiency in the systems of Tween 20/diammonium hydrogen phosphate,... 

    Qualitative Study of the Dynamic Adsorption Layer by Bubble Rising Method

    , M.Sc. Thesis Sharif University of Technology Bahmani, Alireza (Author) ; Bastani, Dariush (Supervisor) ; Lotfi, marzieh (Co-Advisor)
    Abstract
    Surface phenomena and dynamic interfacial properties plays a significant role in multiphase gas-liquid & liquid-liquid processes applied in different industrial applications. However, current laboratory equipment and represented methods for dynamic and unsteady state condition caused by motivation of interface of two phases (like rising bubble), in purpose of qualitative investigation of interphase properties are not satisfying enough. Also, common modeling methods are represented with lots of modified assumptions which are not validated properly with experimental results. In current thesis, with development of laboratory tools and applying the “rising bubble method” for investigating the... 

    Experimental Investigation of Surfactant Flooding for EOR in Layered Heavy Oil Reservoirs using Micromodel Apparatus

    , M.Sc. Thesis Sharif University of Technology Morshedi, Saeid (Author) ; Rashtchian, Davood (Supervisor) ; Massihi, Mohsen (Supervisor) ; Ghazanfari, Mohammad Hossein (Supervisor)
    Abstract
    Nowadays, due to limitation of production from conventional oil reservoirs, enhanced recovery from heavy oil reservoirs are of great concern. In heavy oil reservoirs, only 5% of initial oil in place (IOIP) is producible due to high viscosity. Water flooding increases oil recovery just up to 10% which is due to improper mobility ratio. One of popular methods for increasing oil recovery is injection of chemical materials. Chemical methods are used in reservoirs that have high degree of heterogeneity like heterogeneous and layered reservoirs. These heterogeneities cause diversion and loss of injected water which leads to remaining of oil in its place. Using surface active agents, as a popular... 

    Highly efficient hydroxyapatite/TiO2 composites covered by silver halides as E. coli disinfectant under visible light and dark media

    , Article Photochemical and Photobiological Sciences ; Volume 12, Issue 10 , October , 2013 , Pages 1787-1794 Azimzadehirani, M ; Elahifard, M ; Haghighi, S ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
    Abstract
    TiO2-based photocatalysts are seen as the most common agents for the photodegradation of bacteria. In this study, AgCl/TiO2, hydroxyapatite(Hp)/AgCl/TiO2, AgI/TiO2, and Hp/AgI/TiO2 were prepared by the deposition-precipitation method on P25 TiO2 nanoparticles and were characterized by XRD, SEM, FT-IR, EDX and BET methods. The prepared composites showed high efficiency for the inactivation of Escherichia coli (E. coli) bacteria under visible light and in dark media with different catalyst amounts of 12 and 24 mg, respectively. In less than 30 min, AgI/TiO2, prepared by the combination of cationic surfactant and PVPI2, disinfected 1 × 10(7) colony-forming units of E. coli completely. However,... 

    Study on biodegradation of Mazut by newly isolated strain Enterobacter cloacae BBRC10061: Improving and kinetic investigation

    , Article Iranian Journal of Environmental Health Science and Engineering ; Volume 10, Issue 2 , 2013 ; 17351979 (ISSN) Khorasani, A. C ; Mashreghi, M ; Yaghmaei, S ; Sharif University of Technology
    2013
    Abstract
    Mazut as a source content of various hydrocarbons is hard to be degraded and its cracking could turn mazut into useful materials. Nevertheless degradation of mazut by routine methods is too expensive but application of indigenous microorganisms as biocatalysts could be effective and important to lower the costs and expand its consumption. Mazut biodegradation can be improved using various strategies; Therefore in this study newly isolated strain Enterobacter cloacae BBRC 10061 was used in a method of gradual addition of mazut into medium and its results were compared with simple addition method. To investigate degradation of mazut by BBRC 10061, influence of increase of mazut concentration... 

    The effect of cationic and anionic surfactants on the nanostructure and magnetic properties of Yttrium Iron Garnet (YIG) synthesized by a sol-gel auto combustion method

    , Article Russian Journal of Non-Ferrous Metals ; Volume 53, Issue 4 , 2012 , Pages 308-314 ; 10678212 (ISSN) Emami, S ; Madaah Hosseini, H. R ; Dolati, A ; Sharif University of Technology
    Abstract
    Yttrium Iron Garnet (YIG) powders were synthesized by a sol-gel auto-combustion method using cationic and anionic surfactants with different values and different calcination times and temperatures. The final products were characterized by DTA/TG, XRD, TEM and VSM techniques. The results showed a decrease in calcination temperature and crystallite size in the presence of a cationic surfactant, while no significant effect was observed using an anionic surfactant. Magnetic properties of YIG powders were improved as an optimum value of cationic surfactant was used  

    Study of the Effect of Surfactant and Fe Concentration on the Size and Physical Properties of Magnetic Fe-Au Core-Shell Nano Particles, Synthesized Via Reverse Nicelle

    , M.Sc. Thesis Sharif University of Technology Molavi Kakhki, Amin (Author) ; Simchi, Abdolreza (Supervisor) ; Abachi, Parvin (Supervisor)
    Abstract
    The aim of this research is to study the effect of surfactant type and the concentration reactants on the size, shape and magnetic properties of iron-gold core-shell magnetic nanoparticles (NPs) useable for biomedical application. The reverse micelle procedure was employed to synthesize iron NPs using two surfactants of CTAB and SDS. A gold shell with a thickness in the range of 10 to 40 nm was induced by reverse micelle method in order to prevent oxidation of the iron core. The size and morphology of NPs were studied by transition electron microscopy (TEM). It was found that the size of NPs increases by the increasing the reactants concentration while the morphology of the NPs was not... 

    Study of Solvent-Solvent and Solute-Solvent Interactions and Measurement of Solvatochromic Parameters in Mixture of Molecular Solvents with Solvents

    , M.Sc. Thesis Sharif University of Technology Kohantorabi, Mona (Author) ; Gholami, Mohammad (Supervisor) ; Rahman Setayesh, Shahrbano (Supervisor) ; Salari, Hadi (Co-Advisor)
    Abstract
    Solvent-solvent and solute-solvent interactions were investigated in mixtures of Triton X-100 with water, methanol, ethanol, 1-propanol, tetrahydrofuran and butyl acetate. Solvatochromic parameters, including normalized polarity (E_T^N), dipolarity-polarizability (), hydrogen-bond donar (), and hydrogen-bond acceptor () abilities, were determined in these mixtures. We observed similar behavior for E_T^N and  in TX-100/alcohols mixtures. Parameters confirmed the preferential solvation in mixtures of surfactant and solvents.
    Experimental data were handled in preferential solvation model. Six binary systems exhibit a complex behavior for all three indicators. It was shown that... 

    The Effect of Surfactant Agents on the Superhydrophobic Properties of Silica Coatings Synthesis by Sol-gel

    , M.Sc. Thesis Sharif University of Technology Ziaee, Hamed (Author) ; Dolati, Abolghasem (Supervisor)
    Abstract
    The purpose of this research is producing one phase silica superhydrophobic coating by sol-gel method and drying temperature less than 200 degrees. For preparing micrometer and nanometer scaled hierarchical structure based on silica, TEOS precursor and Fumed Silica nanoparticles were used by density of 43/30 cc/lit and 6/52 gr/lit in order to provide desired roughness in the range of 40 nm. Moreover, HMDS surface modifying agent was used for reducing the surface energy of coating, which is not a danger to the environment in comparison to the same substances. The best Contact Angle is 155 degree and the best Sliding Angle is less than 5 degree. For instance, it was created with the...