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surface-active-agents
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Azo dye removal via surfactant-assisted polyvinylidene fluoride membrane
, Article Environmental Health Engineering and Management ; Volume 8, Issue 1 , 2021 , Pages 25-32 ; 24233765 (ISSN) ; Mousavi, A ; Bagheri Lotfabad, T ; Heydarinasab, A ; Yaghmaei, S ; Sharif University of Technology
Kerman University of Medical Sciences
2021
Abstract
Background: Recently, concerns have been raised regarding the environmental and public health safety of azo dyes, the most widely used synthetic dyes. The membrane technique has been introduced as one of the efficient methods for dye removal treatments. Polyvinylidene fluoride (PVDF) membrane manipulated by surfactants was studied for removal of the azo dye, carmoisine. Methods: PVDF membrane was prepared via non-solvent-induced phase separation (NIPS) and used to remove the azo dye, carmoisine. Three nonionic surfactants including Tween 20, Tween 60, and Tween 80 were used individually as additives in casting solutions to improve PVDF membrane properties. Results: Fourier-transform infrared...
Evaluation of a recycling bioreactor for biosurfactant production by Pseudomonas aeruginosa MR01 using soybean oil waste
, Article Journal of Chemical Technology and Biotechnology ; Volume 91, Issue 5 , 2016 , Pages 1368-1377 ; 02682575 (ISSN) ; Ebadipour, N ; Roostaazad, R ; Sharif University of Technology
John Wiley and Sons Ltd
Abstract
This study deals with the large-scale production of biosurfactant from soybean oil soapstock by Pseudomonas aeruginosa MR01. The production of biosurfactant was carried out in a newly designed bioreactor equipped with recycling flow under three operational conditions. Kinetic studies were conducted at both shake flask and 5-L bioreactor scales during fermentation in a soapstock medium. Mathematical equations were developed to model the kinetic patterns at both scales. RESULT: Statistical analyses demonstrated the goodness of fit, with regression r-squared, R2, between 0.97and 0.99 for different models. Furthermore, biosurfactant concentration in the bioreactor including the recycling flow,...
Theoretical and experimental investigations of the inverse emulsion polymerization of acrylamide
, Article Journal of Applied Polymer Science ; Volume 132, Issue 22 , February , 2015 ; 00218995 (ISSN) ; Shahrokhi, M ; Ahmad Ramazani, S. A ; Vafa, E ; Sharif University of Technology
John Wiley and Sons Inc
2015
Abstract
In this study, the inverse emulsion polymerization modeling of polyacrylamide with population balance equations (PBEs) was performed. The PBEs were derived on the basis of the zero-one kinetic model. The effects of the surfactant steric barrier and surfactant reaction with radicals, including monomeric radicals, on the radical entry rate into the particle were taken into account. In the modified model, the coagulation phenomenon was included through consideration of the effects of forces not included in the Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory; these include hydration and steric forces in addition to DLVO forces. The effects of the surfactant and initiator concentrations on...
Improvements in permeation and fouling resistance of PVC ultrafiltration membranes via addition of Tetronic-1107 and Triton X-100 as two non-ionic and hydrophilic surfactants
, Article Water Science and Technology ; Volume 74, Issue 6 , 2016 , Pages 1469-1483 ; 02731223 (ISSN) ; Seyedi, S. M ; Rabiei, H ; Alvandifar, N ; Sharif University of Technology
IWA Publishing
Abstract
Two non-ionic and hydrophilic surfactant additives, Tetronic-1107 and Triton X-100, were added to poly(vinyl chloride)/NMP polymeric solution to prepare ultrafiltration membranes via immersion precipitation. Surfactants at three different weight percentages up to 6 wt% were added, and the fabricated membranes were characterized and their performance for water treatment in the presence of bovine serum albumin (BSA) as a foulant was assessed. The scanning electron microscopy images indicated remarkable changes in morphology due to higher thermodynamic instability after surfactant addition. The membranes are more porous with more macro-voids in the sub-layer. Plus, the membranes become more...
Efficient biodegradation of naphthalene by a newly characterized indigenous achromobacter sp. FBHYA2 isolated from Tehran oil refinery complex
, Article Water Science and Technology ; Volume 66, Issue 3 , March , 2012 , Pages 594-602 ; 02731223 (ISSN) ; Borghei, S. M ; Hassani, A. H ; Yakhchali, B ; Ardjmand, M ; Zeinali, M ; Sharif University of Technology
IWA Pub
2012
Abstract
A bacterial strain, FBHYA2, capable of degrading naphthalene, was isolated from the American Petroleum Institute (API) separator of the Tehran Oil Refinery Complex (TORC). Strain FBHYA2 was identified as Achromobacter sp. based on physiological and biochemical characteristics and also phylogenetic similarity of 16S rRNA gene sequence. The optimal growth conditions for strain FBHYA2 were pH 6.0, 30°C and 1.0% NaCl. Strain FBHYA2 can utilize naphthalene as the sole source of carbon and energy and was able to degrade naphthalene aerobically very fast, 48 h for 96% removal at 500 mg/L concentration. The physiological response of Achromobacter sp., FBHYA2 to several hydrophobic chemicals...
Preparation of sorbitan stearate
, Article 2nd International Multi-Conference on Engineering and Technological Innovation, IMETI 2009, Orlando, FL, 10 July 2009 through 13 July 2009 ; Volume 1 , 2009 , Pages 81-85 ; 193427268X (ISBN); 9781934272688 (ISBN) ; Alemzadeh, I ; Vossoughi, M ; Inter-American Organization for Higher Education (IOHE); International Institute of Informatics and Systemics (IIIS); Journal of Systemics, Informatics and Cybernetics (JSCI) ; Sharif University of Technology
International Institute of Informatics and Cybernetics, IIIC
2009
Abstract
The present paper relates to an improved method for making surfactant esters, especially sorbitan monostearate and tristearate. Sorbitan esters of fatty acid, stéarate are derived from a reaction between sorbitan and fatty acid. Method of sorbitan ester production needs addition of catalyst. Sorbitan stéarate production was studied using chemical catalyst. Two steps process leading sorbitan production under atmospheric and vacuum pressure with acid catalyst resulted dehydrated product at optimal residence time of 195 min at 180°C for atmospheric conditions and optimalresidence time of 150 min at the same temperature respectively. Sorbitan stearate production was studied by utilizing sorbitan...
Herschel-Bulkley rheological parameters of lightweight colloidal gas aphron (CGA) based fluids
, Article Chemical Engineering Research and Design ; Volume 93 , 2015 , Pages 21-29 ; 02638762 (ISSN) ; Arabloo, M ; Ghazanfari, M. H ; Rashtchian, D ; Sharif University of Technology
Institution of Chemical Engineers
2015
Abstract
The proper understanding of rheological characteristics of CGA based fluids is of crucial importance in determining the performance of the fluid, in order to maintain the most effective fluid properties for safe, efficient, and economical drilling operation. This paper presents a concise investigation on the effect of concentration of the three main components of a novel environmentally friendly lightweight CGA based drilling fluid, i.e., xanthan gum biopolymer, starch, and biosurfactant, to the Herschel-Bulkley rheological model parameters. The three parameters of Herschel-Bulkley model, i.e., yield stress, fluid consistency, and fluid flow index were calculated by fitting the experimental...
Characterization of viscous fingering during displacements of low tension natural surfactant in fractured multi-layered heavy oil systems
, Article Chemical Engineering Research and Design ; Volume 96 , 2015 , Pages 23-34 ; 02638762 (ISSN) ; Shokrollahi, A ; Ghazanfari, M. H ; Rashtchian, D ; Sharif University of Technology
Institution of Chemical Engineers
2015
Abstract
Characterization of viscous fingering in low tension displacements especially for heavy oil surfactant pair in heterogeneous systems is neither straight forward nor well understood. In this work layered porous models containing fractures with different geometrical properties were used and the finger behavior during displacement of LTNS, as a new EOR agent, in heavy oil was quantified. Dynamic propagation of the fingers independent to the type of heterogeneity is well correlated with the dimensionless displacement time in a linearly form. And also, the rate of finger growth is nearly independent to the type of medium heterogeneity. When injection is scheduled through high permeable region in...
Surfactant effects on the efficiency of oil sweeping from the dead ends: Numerical simulation and experimental investigation
, Article Chemical Engineering Research and Design ; Volume 94 , 2015 , Pages 173-181 ; 02638762 (ISSN) ; Ramazani, S. A. A ; Kamyabi, M ; Sharif University of Technology
Institution of Chemical Engineers
2015
Abstract
Highlights: The objective of this work is to investigate the effects of the surfactants on the oil extraction from the dead ends through the numerical simulations and experimental evidences. The volume of fluid approach in the frame of the finite volume method has been used for numerical simulations in 2-D domain and experimental flooding tests have been done using a glassy micro-model. The effects of the water-oil, water-wall and oil-wall interfacial tensions have been investigated numerically and some results are compared to experimental flooding results. Simulations have been done in the cases of water-wet, neutralized-wet and oil-wet micro-models also. The numerical results show that in...
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) ; 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...
ANFIS modeling of rhamnolipid breakthrough curves on activated carbon
, Article Chemical Engineering Research and Design ; Volume 126 , 2017 , Pages 67-75 ; 02638762 (ISSN) ; Sasanipour, J ; Haratipour, P ; Alizad, M ; Vafaee Ayouri, M ; Sharif University of Technology
Institution of Chemical Engineers
2017
Abstract
Owning to interesting properties of biosurfactants such as biodegradability and lower toxicity, they have broad application in the food industry, healthy products, and bioremediation as well as for oil recovery. The present study was aimed to develop a GA-ANFIS model for predicting the breakthrough curves for rhamnolipid adsorption over activated carbon. To that end, a set of 296 adsorption data points were utilized to train the proposed FIS structure. Different graphical and statistical methods were also used to evaluate the model's accuracy and reliability. Results were then compared to those of the previously reported Artificial Neural Network (ANN) and Group Method Data Handling (GMDH)...
Electrochemical deposition of Ni-TiN nanocomposite coatings and the effect of sodium dodecyl sulphate surfactant on the coating properties
, Article Bulletin of Materials Science ; Volume 39, Issue 4 , 2016 , Pages 1021-1027 ; 02504707 (ISSN) ; Dolati, A ; Aghababazadeh, R ; Lalegani, Z ; Sharif University of Technology
Indian Academy of Sciences
2016
Abstract
Ni-TiN nanocomposite coatings were prepared by using electrochemical deposition in a Watt's bath containing TiN particles to increase the hardness of Ni. The effects of deposition current density, electrolyte agitation speed and the number of particles in the solution on the amount of incorporated particles in the coating process were investigated. The optimum deposition current density of 4 A dm-2 and agitation speed of 450 rpm were obtained. The effect of sodium dodecyl sulphate (SDS) anionic surfactant on the amount of particles in the coatings was investigated. It was observed that the maximum amount of incorporated particles, with a value of 7.5% by volume, was created in the current...
Simulation and control of monomer conversion in a continuous emulsion polymerization reactor
, Article IFAC Proceedings Volumes (IFAC-PapersOnline), 7 June 2015 through 10 June 2015 ; Volume 48, Issue 8 , 2015 , Pages 315-320 ; 14746670 (ISSN) ; Shahrokhi, M ; Abedini, H ; Vafa, E ; Guay, M ; Gopaluni, B ; Huang, B ; Findeisen, R ; Sharif University of Technology
IFAC Secretariat
2015
Abstract
A detailed pseudo-bulk model has been used for prediction of conversion and particle size distribution (PSD) of vinyl acetate in a continuous emulsion polymerization reactor. Finite volume (FV) and moment techniques are applied for solving population balance equation under continuous operation. It is found that both methods can predict sustained oscillations in the monomer conversion, however the FV method matches the experimental data better than the moment method. The monomer conversion and free surfactant concentration are controlled via two single control loops. In this work, a new control strategy for controlling monomer conversion has been proposed. It has been shown that monomer...
Experimental investigation of asp flooding in fractured heavy oil five-spot systems
, Article 74th European Association of Geoscientists and Engineers Conference and Exhibition 2012 Incorporating SPE EUROPEC 2012: Responsibly Securing Natural Resources, 4 June 2012 through 7 June 2012 ; 2012 , Pages 3924-3928 ; 9781629937908 (ISBN) ; Ghazanfari, M. H ; Masihi, M ; Rashtchian, D ; Sharif University of Technology
European Association of Geoscientists and Engineers, EAGE
2012
Abstract
Although alkaline-surfactant-polymer flooding is proved to be efficient for oil recovery from heavy oil reservoirs, the displacements mechanism/efficiency of this process in fractured systems needs to more discussion, especially in five-spot patterns. In this work, several ASP flooding test were performed on fractured micromodels which were initially saturated with heavy oil at constant flow rate and different fracture geometrical characteristics conditions. The ASP solutions are constituted from 5 polymers i.e. four synthetic polymers include three hydrolyzed polyacrylamide with different molecular weight as well as a non-hydrolyzed polyacrylamide and a biopolymer, 2 surfactants i.e. a...
Optimal well location in surfactant flooding by genetic algorithm
, Article 74th European Association of Geoscientists and Engineers Conference and Exhibition 2012 Incorporating SPE EUROPEC 2012: Responsibly Securing Natural Resources ; 2012 , Pages 5489-5491 ; 9781629937908 (ISBN) ; Chahardahcherik, M ; Sharif University of Technology
European Association of Geoscientists and Engineers, EAGE
2012
Abstract
As many fields around the world are reaching maturity, the need to develop new tools that allows reservoir engineering to optimize reservoir performance is becoming more demanding. One of the more challenging and influential problems along these lines is the well placement optimization problem. Determining of the location of new wells is a complex problem that depends on reservoir and fluid properties, well and surface equipment specifications, and economic criteria. Various approaches have been proposed for this problem. Among those, direct optimization using the simulator as the evaluation function, although accurate, is in most cases infeasible due to the number of simulations required....
Wettability modification, interfacial tension and adsorption characteristics of a new surfactant: Implications for enhanced oil recovery
, Article Full ; Volume 185 , 2016 , Pages 199-210 ; 00162361 (ISSN) ; Ghazanfari, M. H ; Rashtchian, D ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
This paper concerns with the interfacial tension (IFT), wettability modification and adsorption behavior of a new plant-based surface active agent, Zizyphus Spina Christi, onto sandstone minerals which has been rarely attended in the available literature. Both kinetics and equilibrium adsorption data were obtained from batch mode tests. It was revealed that Freundlich isotherms matched better fit to the equilibrium data which implied that multilayer coverage of Zizyphus Spina Christi onto the sandstone particle surfaces was more likely to occur. Analysis of experimental kinetic data based on intraparticle diffusion model disclosed that the intraparticle diffusion mechanism is not the only...
Nickel-cobalt layered double hydroxide ultrathin nanosheets coated on reduced graphene oxide nonosheets/nickel foam for high performance asymmetric supercapacitors
, Article International Journal of Hydrogen Energy ; 2017 ; 03603199 (ISSN) ; Rahimi, S ; Mohammadi, R ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
Here in, for the first time, we report a new and simple procedure for preparing reduced graphene oxide/nickel-cobalt double layered hydroxide composite on the nickel foam (Ni-Co LDH/rGO/NF) via a fast and simple two-step electrochemical method including potentiostatic routes in the presence of CTAB as a cationic surfactant. Graphene oxide coated nickel foam prepared by simple immersion method. After that, the prepared electrode reduced electrochemically to obtain rGO/NF electrode. Finally, the rGO/NF electrode was used as cathode for electrodeposition of Ni-Co LDH in the presence of CTAB as cationic surfactant. The prepared electrodes were characterized by field emission scanning electron...
Vertically standing Cu2O nanosheets promoted flower-like PtPd nanostructures supported on reduced graphene oxide for methanol electro-oxidation
, Article Electrochimica Acta ; Volume 259 , 2018 , Pages 36-47 ; 00134686 (ISSN) ; Rezaee, S ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The present study reports a simple electrochemical approach to the fabrication of a new nanocomposite containing PtPd nanoflowers (NFs) promoted with two-dimensional (2D) nanosheets (NSs) structure cuprous oxide (Cu2O) supported on reduced graphene oxide (rGO) (PtPd-NFs/Cu2O-NSs/rGO). Scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectra, Raman spectroscopy, and energy dispersive X-ray spectroscopy are used for characterization of the PtPd-NPs/Cu2O-NPs/rGO. SEM images showed that vertical-standing arrays of Cu2O with an edge length up to 1 μm and thickness of about 20 nm are electrodeposited on the surface of rGO film. Also, PtPd needle-like NFs with visible and...
Nickel-cobalt layered double hydroxide ultrathin nanosheets coated on reduced graphene oxide nonosheets/nickel foam for high performance asymmetric supercapacitors
, Article International Journal of Hydrogen Energy ; Volume 43, Issue 4 , 2018 , Pages 2256-2267 ; 03603199 (ISSN) ; Rahimi, S ; Mohammadi, R ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Here in, for the first time, we report a new and simple procedure for preparing reduced graphene oxide/nickel-cobalt double layered hydroxide composite on the nickel foam (Ni-Co LDH/rGO/NF) via a fast and simple two-step electrochemical method including potentiostatic routes in the presence of CTAB as a cationic surfactant. Graphene oxide coated nickel foam prepared by simple immersion method. After that, the prepared electrode reduced electrochemically to obtain rGO/NF electrode. Finally, the rGO/NF electrode was used as cathode for electrodeposition of Ni-Co LDH in the presence of CTAB as cationic surfactant. The prepared electrodes were characterized by field emission scanning electron...
An experimental investigation of nanoemulsion enhanced oil recovery: Use of unconsolidated porous systems
, Article Fuel ; Volume 251 , 2019 , Pages 754-762 ; 00162361 (ISSN) ; Tabzar, A ; Ghasemi, V ; Mohammadzadeh, O ; Pourafshary, P ; Rezaei, N ; Zendehboudi, S ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Utilization of nanoparticles in oil and gas industry has attracted considerable attention of engineers and researchers. In this article, the feasibility of nanoemulsion flooding is investigated as a method for Enhanced Oil Recovery (EOR) through coreflooding experiments, using a packed bed and real reservoir fluids. Nine different mixtures of the solvent, surfactant, and nanoparticles in the form of a nanoemulsion phase are generated and used to recover the oil in the context of an EOR process. Various tests are conducted to determine the properties of porous medium and fluids. To study the production performance of this EOR technique, pressure drop across the packed bed are measured, along...