Department of Petroleum Engineering (1990 - Present)
chemical engineering
, England, England
Chemical Engineering - Petrochemical
, Amirkabir University of Technology,
As a noteworthy salt hydrate, sodium sulfate decahydrate or Glauber salt can be used as a phase change thermal energy storage material. Kinetic parameters of sodium sulfate decahydrate salt solution are evaluated experimentally. Instead of the traditional polythermal and isothermal methods, a novel constant temperature experimental method (based on the turbidity titration) was adopted to experimentally illustrate the induction time and metastable zone width, in unseeded batch crystallization for sodium sulfate decahydrate salt solution at different temperatures (7, 9, 10, 13, 16, 19, 22??C) and supersaturation ratio (1.01–1.43). We determined crystallization thermodynamics parameters, solubility, and supersolubility, of sodium sulfate dec
Experimental and thermodynamic modeling results for hydrate dissociation conditions in carbon dioxide + THF + NaCl + water systems were reported. Four different aqueous solutions of THF and NaCl (0.05 mass fraction of NaCl, 0.05 mass fraction of THF: namely solution 1; 0.10 mass fraction of NaCl, 0.05 mass fraction of THF: namely solution 2; 0.05 mass fraction of NaCl, 0.20 mass fraction of THF: namely solution 3; 0.10 mass fraction of NaCl, 0.20 mass fraction of THF: solution 4) were studied in this work. An isochoric pressure – search method was used to perform the measurements. The equilibrium dissociation conditions are reported in the ranges of (0.92–3.89) MPa and (280.9–292.9 K). NaCl acts as an inhibitor in all of
In recent years, in order to obtain improved mechanical, thermal, electrical and barrier/transport properties, aligned carbonaceous nanomaterials/polymer nanocomposite films have been receiving growing attention. Correspondingly, the edge oxidized graphene oxide (EOGO) nanoplatelets alignment influence on the structure of the polyethersulfone (PES) membrane films for potential applications in water treatment field has been investigated. Aligned GO/PES nanocomposite membrane films were prepared by non-solvent phase inversion technique after the starting sol phase was preliminarily exposed to high electric fields (50 kV m− 1). Either AC (100, 1000 Hz) or DC mode electric fields were alternatively employed, and the results from both vertical
Colloidal Gas Aphrons (CGA), consist of gas bubbles with diameters ranging from 10 to 100 micron, surrounded by a thin aqueous surfactant film. This fluid combines certain surfactants and polymers to create the systems of microbubbles. The function of surfactant in CGAs is to produce the surface tension to contain the aphrons. Also, a biopolymer needs to be considered in the formulation as a viscosifier as well as a stabilizer. The aphron-laden fluid appears to be particularly well suited for drilling through depleted zones. The unique feature of aphron based fluids is to form a solid free, tough, and elastic internal bridge in pore networks or fractures to minimize deep invasion using air microbubbles. This microenvironment seal readily cl
In this study, the effect of gamma alumina-based molybdenum oxide nanoparticles, on the viscosity reduction of extra-heavy crude oil in a catalytic cracking process in atmospheric pressure and at 250-350 degrees C investigated for the first time. Molybdenum oxide nanoparticles synthesized using the polyol method and heating by microwave radiation. According to the dynamic light scattering (DLS) analysis, obtained nanoparticles have an average size of 6 nm. These nanoparticles coated on gamma-alumina powder using the novel method of per-vaporation, and through this method, 0.011 g of molybdenum oxide nanoparticles coated over per 1 g of catalyst, during 14 days. The performance of the synthesized catalysts in the cracking process of extra-h
For the first time, numerous experiments were carried out to evaluate the effect of electric field (EF) on the mechanism of naturally occurring THF hydrate formation. The Statistical Package for the Social Sciences (SPSS) software was utilized to analyze the experimental data. First, the effect of static electric field (SEF) strength on nucleation temperature (T-nuc) and growth time (t-growth) studied. Based on the statistical results, increasing the intensity of SEF induces nucleation at a relatively high temperature. Furthermore, the completion of solidification takes a longer time than the same process in the absence of SEF. The notable point is that by switching a SEF to a pulsed electric field (PEF) of equal voltage, the EF effectivene
This research synthesized polybutadiene nanoparticles and investigated the induction time for their nucleation under different supersaturations and their cross-linking to be utilized in an asymmetric membrane synthesis. Purchased (bulk) polybutadiene was dissolved in toluene and then ethanol was added dropwise to the solution as an antisolvent. The induction time, ie, the time interval between adding the last drop of ethanol till appearance of a turbidity due to polybutadiene nucleation, was determined. The nucleation mechanism was investigated. Dependence of the induction time on supersaturation suggests that the mechanism of nucleation is primary. The correlation coefficient was obtained as 0.986. After formation, the nanoparticles were c
Research subject: The use of nanoparticles, especially nano-antibiotics, increases their efficacy. More uniform release of antibiotics is one of the benefits of being nano. They can also be made using ointment or banderol to absorb through the skin to the infection, thereby reducing its side effects. Amoxicillin is one of the most widely used antibiotics in the world which can be prevented by increasing the use of other strong antibiotics if promoted as nanoparticles. Determining the mechanism of nanoparticle formation of this drug is an important factor for its commercial production.Research approach: The purpose of this study was to determine the nucleation mechanism and time of induction of crystallization of amoxicillin nanoparticles in
In this study, the effect of gamma alumina-based molybdenum oxide nanoparticles, on the viscosity reduction of extra-heavy crude oil in a catalytic cracking process in atmospheric pressure and at 250-350 C investigated for the first time. Molybdenum oxide nanoparticles synthesized using the polyol method and heating by microwave radiation. According to the dynamic light scattering (DLS) analysis, obtained nanoparticles have an average size of 6 nm. These nanoparticles coated on gamma-alumina powder using the novel method of per-vaporation, and through this method, 0.011 g of molybdenum oxide nanoparticles coated over per 1 g of catalyst, during 14 days. The performance of the synthesized catalysts in the cracking process of extra-heavy crud
In this work, the solubility of methane and ethane were studied in aqueous dispersion of silver nanoparticles (1, 5, and 10?ppm) at temperatures of 1, 2.5, 10, and 11.5??C for methane and 2.5, 5, 10, 15.5??C for ethane and at initial pressures 1 to 5.5 and 0.35–2.15?MPa for methane and ethane, respectively. The nanoparticles were synthesized and characterized through UV–vis spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM) image. The results demonstrated that silver nanoparticles increased the solubility of methane and ethane up to 13 and 16% compared with pure water, respectively. The solubility of methane and ethane were enhanced by increasing the nanoparticles mass loading. The effect of nanopar
Nucleation is a fundamental process widely studied in different areas of industry and biology. This review paper comprehensively discussed the principles of classical nucleation theory (primary homogeneous), and heterogeneous nucleation. In the homogeneous part, the nucleation rate in the transient and intransient state is monitored and also heterogeneous nucleation is covered. Finally, conclusions have been deduced from the collected works studied here, and offers for future studies are proposed.
Gas hydrates, as a novel technology for storage and transportation of natural gases, have attracted many researchers. High pressures and low-temperatures demand, and slow kinetics of hydrates formation are the two critical challenges. In this study, mixed tetrahydrofuran (THF) and aluminum oxide nanoparticles (Al2O3) or graphene oxide (GO) nanosheets solutions were prepared, and their effects on the kinetics of methane hydrate formation were investigated. Also, the mechanism of hydrate formation in the presence of these nanoparticles is discussed. The concentrations in the systems were 5 and 15?wt% for THF, 100, 300, and 400?ppm for GO, and 0.2, 0.4, and 0.6?wt% for Al2O3. It is concluded that 15?wt% THF solutions decline the induction time
In this study, the effect of gamma alumina-based molybdenum oxide nanoparticles, on the viscosity reduction of extra-heavy crude oil in a catalytic cracking process in atmospheric pressure and at 250–350 C investigated for the first time. Molybdenum oxide nanoparticles synthesized using the polyol method and heating by microwave radiation. According to the dynamic light scattering (DLS) analysis, obtained nanoparticles have an average size of 6 nm. These nanoparticles coated on gamma-alumina powder using the novel method of per-vaporation, and through this method, 0.011 g of molybdenum oxide nanoparticles coated over per 1 g of catalyst, during 14 days. The performance of the synthesized catalysts in the cracking process of extra-heavy cr
The present study aims to investigate the water diffusivity into polystyrene/ calcium sulfate (PS/CaSO4) nanocomposite samples as a threat to the intended reinforcing properties. For this purpose, CaSO4 nanoparticles were synthesized through a chemical reaction using polyethylene glycol as the stabilizing agent. The polystyrene/calcium sulfate nanocomposites were fabricated through in situ polymerization of styrene monomer and stearic acid coated CaSO4 nanoparticles. SEM analysis was applied to determine the size and shape of the produced nanoparticles. In addition, TEM analysis was applied to study the general morphology and structure of the nanocomposites in order to confirm the PS/CaSO4 nanocomposites formation. FTIR analysis was employe
In the present study, a novel pervaporation technique was used to impregnate nano-activated carbon (nAC) on the lightweight expanded clay aggregate (LECA). The nAC was prepared from powdered activated carbon. XRD, FESEM, EDX, TEM, and BET analyses were used to investigate the adsorbent structure and morphology. FESEM and TEM demonstrated that the provided nanoparticles have dimensions smaller than 30 nm. Also, the influence of various parameters on the performance of impregnated nano-activated carbon on LECA (nAC-LECA) was investigated. These parameters include pH, initial metal concentration, contact time, adsorbent dose, and temperature. The investigations showed that the maximum amount of lead removal can be achieved in pH = 6. The
since the gas hydrate inhibition is important in the transmission of natural gas, the effect of temperature and of cetyltrimethyl ammonium bromide (CTAB) as the inhibitor on hydrate formation tetrahydrofuran (THF) is studied .First, tetrahydrofuran hydrate at 2.5, 3, 3.5 and 4 degrees Celsius and 30,25,20,15% weight of THF at atmospheric pressure has been studied and determined induction time and equilibrium temperature graph . Then tested in the presence of CTAB 0.5, 1, 1.5 and 2% weight as hydrate inhibitor and investigated the effect of CTAB on the kinetics of hydrate formation and induction time. The results show that at a constant temperature over time with the addition of CTAB to hydrate the induction time increased. Also, in some inh
Herein, we have evaluated the impact of orientated edge‐oxidized graphene oxide nanoplatelets (EOGO) in polyether sulfone (PES) membrane on the pure water permeability (PWP) and organic dye molecule rejection values. Aligned PES/EOGO nanocomposite films were prepared through electric field induction. Morphological, structural, and chemical‐physical characterizations including atomic force microscopy, thermogravimetric analysis (TGA), contact angle, zeta potential, porosity, and PWP measurements were carried out. The results revealed successful aligned/oriented PES/EOGO nanocomposite formation at low‐to‐moderate EOGO loadings. Membrane function tests demonstrated an increase in water permeability at higher EOGO contents, up to 0.5 wt
The comparative sorption studies were carried out to investigate the performance of keratin nanoparticles (KNPs) and magnetic KNPs (MKNPs) for Zn(II) uptake. MKNPs showed remarkably higher Zn(II) removal due to the lower keratin weight percent in its structure (8.4%). MKNPs revealed relatively uniform Zn(II) removal within pH range between 4.0 to 6.0 at the temperature of 25?C rather than KNPs. Both KNP and MKNP exhibited two-stage kinetic behavior and reached to their equilibrium adsorption capacity within 30 min. The adsorption of Zn(II) on KNPs and MKNPs followed pseudo second order kinetic model. It was found that the experimental data were best fitted to Sips or Redlich-Peterson isotherm when KNP was used as biosorbent. Unlike KNP, MKN
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