Thermodynamics,
Volume 8, Issue 4 , October 2011, , Pages 57-64
Polymer Engineering and Technology,
Volume 9, Issue 1 , January 2012, , Pages 60-69
Petroleum and Reservoir Engineering
Volume 9, Issue 3 , July 2012, , Pages 63-74
Process Control and Engineering, Process Safety, HSE
Volume 11, Issue 4 , October 2014, , Pages 64-75
Transport Phenomena,
Volume 8, Issue 3 , July 2011, , Pages 64-77
Separation Technology,
Volume 7, Issue 4 , October 2010, , Pages 64-70
Modeling and Simulation
Volume 2, Issue 2 , April 2005, , Pages 64-71
Abstract
KATAPAK-S is a type of structured catalytic packing, which is used in reactive distillation processes. The dry pressure drop characteristic (the pressure drop in the absence of liquid flow) is of significant importance for the investigation of process hydrodynamics. In this paper, the dry pressure drop ...
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KATAPAK-S is a type of structured catalytic packing, which is used in reactive distillation processes. The dry pressure drop characteristic (the pressure drop in the absence of liquid flow) is of significant importance for the investigation of process hydrodynamics. In this paper, the dry pressure drop within the catalyst packed channels of KATAPAK-S has been investigated using Computational Fluid Dynamics (CFD). Results of the CFD simulations were validated using experimental pressure drop data and empirical correlations. The CFD results showed an excellent agreement with theoretical and experimental data. Keywords: KATAPAK-S structures, Pressure drop, Structured packing, CFD
Modeling and Simulation
Volume 9, Issue 4 , October 2012, , Pages 65-79
Reaction Engineering, Kinetics and Catalysts,
Volume 1, Issue 1 , April 2004, , Pages 65-70
Modeling and Simulation
Volume 9, Issue 2 , April 2012, , Pages 66-83
Transport Phenomena,
Volume 11, Issue 3 , July 2014, , Pages 67-73
Modeling and Simulation
Volume 7, Issue 2 , April 2010, , Pages 68-77
Separation Technology,
M. Shokouhi; M. Hosseini-Jenab; A. Mehdizadeh; A. Naser Ahmadi; A. H. Jalili
Volume 12, Issue 1 , January 2015, , Pages 68-77
Abstract
In this paper, the experimental investigation ofsolubility and initial absorption rate of CO2 gas in methanol and 1-ethyl-3-methylimidazolium ethylsulfate, [emim][EtSO4] solution of amine-functionalized imidazolium based ionic liquids, namely 1-(3- aminopropyl)-3-methylimidazolium, [apmim], with tetrafluoroborate, ...
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In this paper, the experimental investigation ofsolubility and initial absorption rate of CO2 gas in methanol and 1-ethyl-3-methylimidazolium ethylsulfate, [emim][EtSO4] solution of amine-functionalized imidazolium based ionic liquids, namely 1-(3- aminopropyl)-3-methylimidazolium, [apmim], with tetrafluoroborate, [BF4], hexafluorophosphate, [PF6] and trifluoromethanesulfonate [OTf] anions are presented. All ionic liquids in this work are synthesized according to literature procedure and all experimental trials were carried out at T=303.15 K and pressure from atmospheric to 40 bar.
Reaction Engineering, Kinetics and Catalysts,
Volume 11, Issue 1 , January 2014, , Pages 69-74
Thermodynamics,
Volume 2, Issue 1 , January 2005, , Pages 71-81
Abstract
The present study investigates the use of different GE mixing rules in cubic equations of state for prediction of phase behavior of multicomponent hydrocarbon systems. To predict VLE data in multicomponent symmetric and asymmetric mixtures such as systems that contain light gases (nitrogen, carbon dioxide, ...
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The present study investigates the use of different GE mixing rules in cubic equations of state for prediction of phase behavior of multicomponent hydrocarbon systems. To predict VLE data in multicomponent symmetric and asymmetric mixtures such as systems that contain light gases (nitrogen, carbon dioxide, etc.) and heavy hydrocarbons, the SRK equation of state has been combined with excess Gibbs energy models. In this study, the PSRK method, developed by Holderbuom and Gmehling for VLE data prediction, is re-examined. To visualize the effect of different mixing rules in predicting VLE data, Wong and Sandler mixing rule was applied. New group and molecular interaction parameters in UNIFAC and W-S models were introduced. These parameters were obtained by regressing the available VLE data. The results of comparisons between applied models and experimental data are presented. These indicate that although all suggested models could provide reasonably good VLE information for the systems containing components of similar size in a wide range of temperatures and pressures, but only PSRK method shows minimum absolute and relative errors for both vapor and liquid compositions in asymmetric systems.
Thermodynamics,
Volume 6, Issue 4 , October 2009, , Pages 73-86
Abstract
In this research, the effect ofmixed salts together with mixed ionic surfactants on dropinterface coalescence time was studied for the system of water (d) / toluene(c) as a model system. Sodium dodecyl sulfate (SDS) and cetyl trimethyl ammonium bromide (CTAB) as anionic and cationic surfactants were ...
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In this research, the effect ofmixed salts together with mixed ionic surfactants on dropinterface coalescence time was studied for the system of water (d) / toluene(c) as a model system. Sodium dodecyl sulfate (SDS) and cetyl trimethyl ammonium bromide (CTAB) as anionic and cationic surfactants were used. Sodium chloride (NaCl) and magnesium sulfate were used as salts. In the first stage of experiments, the system of water and toluene was influenced separately with SDS+NaCl, SDS+MgSO4, CTAB+NaCl and CTAB+MgSO4. It was observed that drop size increased with SDS+NaCl and also with SDS+MgSO4. Partial coalescence times increased for all systems. Overall, this increase of coalescence time was more obvious when CTAB was applied. Also reduction in drop size was observed. In the case ofmixed surfactants with single salt, it was observed that partial coalescence was suppressed for the system with (SDS+CTAB)+MgSO4. On the other hand, drop size decreased and total coalescence time increased. This may be due to the difference between the anions and cations ofthe two salts. For the case ofmixed surfactants with mixed salts, drop size and coalescence time decreased.
Separation Technology,
Volume 3, Issue 2 , April 2006, , Pages 73-84
Reaction Engineering, Kinetics and Catalysts,
H. kalantari; M. Nosrati; S. A Shojaosadati; M. Shavandi
Volume 14, Issue 1 , March 2017, , Pages 74-87
Abstract
In the present study, the effects of four factors including initial sulfide concentration (mg l-1 ), agitation speed (rpm), amount of inoculums (%) and sodium concentration (mg l-1) on removal efficiency (%R) and yield of sulfate production by Thioalkalivibrio versutus from synthetic spent caustic were ...
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In the present study, the effects of four factors including initial sulfide concentration (mg l-1 ), agitation speed (rpm), amount of inoculums (%) and sodium concentration (mg l-1) on removal efficiency (%R) and yield of sulfate production by Thioalkalivibrio versutus from synthetic spent caustic were investigated. For this purpose, experiments are designed by design of experiments (DOE) and Response Surface Methodology uses results of experiments to determine relationship between experimental factors and measured responses. The coefficient of determination (R2) was calculated as 0.9012 and 0.9544 for removal efficiency (%R) and yield of sulfate production (Y_(SO4/S)), respectively. The best local maximum was found to be at initial sulfide concentration 1500 mg/l, agitation speed 180 rpm, inoculum 8%, Na concentration 1.38 M , removal efficiency 96.99%, yield of sulfate production 2.65 and desirability of 0.909. According to these observations and results Thioalkalivibrio versutus is a suitable bacterium for oxidation of sulfide in spent caustic wastewater.
Transport Phenomena,
M. Keshavarz Moraveji*; E. Ghaderi
Volume 12, Issue 2 , April 2015, , Pages 75-87
Abstract
The effective parameters on Ohmic heating in static system containing biosolid-water were studied. The effects of distribution of particles, salinity and electric field strength on electrical conductivity, profiles of temperature, heat generation have been investigated. The experimental data verification ...
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The effective parameters on Ohmic heating in static system containing biosolid-water were studied. The effects of distribution of particles, salinity and electric field strength on electrical conductivity, profiles of temperature, heat generation have been investigated. The experimental data verification with simulation results using computational fluid dynamics (CFD) method were carried out. Governing equations (heat transfer and electrical equations) were discretized with finite element method. The experimental data and CFD results showed that in Ohmic heating process, the current diffusion in all the products is faster than traditional methods and the diffusion rates are equal for both biosolid-liquid phases.
Modeling and Simulation
Volume 10, Issue 3 , July 2013, , Pages 76-87
Separation Technology,
Volume 3, Issue 1 , January 2006, , Pages 77-91
Polymer Engineering and Technology,
Mahnaz Shahzamani; Nadereh Golshan Ebrahimi; Morteza Sadeghi; Fatemeh mostafavi
Volume 13, Issue 3 , July 2016, , Pages 78-88
Abstract
In this study, the relation between the permeation properties and structural characteristics of thermoplastic polyurethane based on polycaprolactone diol, TPU(PCL), and polycaprolactone (PCL) blends is investigated. for the purpsoes of this study, PU, PCL, and TPU/PCL blends containing 20 wt.% and 40 ...
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In this study, the relation between the permeation properties and structural characteristics of thermoplastic polyurethane based on polycaprolactone diol, TPU(PCL), and polycaprolactone (PCL) blends is investigated. for the purpsoes of this study, PU, PCL, and TPU/PCL blends containing 20 wt.% and 40 wt.% PCL were prepared via a solution blending method. The miscibility and good distribution of PCL in the soft segment of PU were represented by the reduced intensity of the band attributed to the NH band at 3400 cm-1 in the Fourier transform infrared (FTIR) spectra. X-ray diffratcion (XRD) results indicated that the amorphous structure of TPU changed to a crystalline one when PCL was added. These results were further confirmed by FTIR and differential scanning calorimetry (DSC) analyses. The permeability of CO2, O2, N2, and CH4 gases at different feed pressures ranging from 12 to 16 bar were determined. A reduction in gas permeability due to the increase in PCL content was observed in the blends. However, gas selectivity did not change with addition of PCL.
Separation Technology,
Volume 10, Issue 4 , October 2013, , Pages 79-84
Transport Phenomena,
Volume 10, Issue 1 , January 2013, , Pages 79-91
Reaction Engineering, Kinetics and Catalysts,
V. Rajendran; P. Abimannan
Volume 13, Issue 2 , April 2016, , Pages 80-87
Abstract
Ultrasound assisted phase-transfer catalyzed preparation of ethyl 2-(4-nitrophenoxy)acetate from the corresponding p-nitrophenol and ethyl 2-bromoacetate using the mild solid base, anhydrous potassium carbonate, under very mild conditions is reported. The solid-liquid reactions were performed in a batch ...
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Ultrasound assisted phase-transfer catalyzed preparation of ethyl 2-(4-nitrophenoxy)acetate from the corresponding p-nitrophenol and ethyl 2-bromoacetate using the mild solid base, anhydrous potassium carbonate, under very mild conditions is reported. The solid-liquid reactions were performed in a batch reactor equipped with reflux condenser, and ultrasonic irradiations were introduced using an ultrasonic bath operating at a frequency of 28 kHz with a power rating of 300 W. The reaction was carried out at 50°C under pseudo-first order conditions and was monitored by gas chromatography (GC). From the experimental data, a rate expression had been developed to explain the kinetic behavior of the reaction from which the apparent rate constant (kapp) of the organic phase was attained. The effects of different operating parameters such as stirring rate, temperature, catalyst loading and kind of Phase-transfer catalysts, base variation and quantity of water, kind of solvents have been investigated to maximize the yield of synthesis of ethyl 2-(4-nitrophenoxy)acetate.