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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Physical Chemistry Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Sol-gel method,Syngas,Fischer-Tropsch synthesis,Co/Fe nano catalyst
- چکیده:
- چکیده انگلیسی: The SiO2 supported cobalt-iron nano catalysts were prepared by the sol-gel method. This research investigated the effects of (Co/Fe) wt.%, different Co/Fe ratio at different temperature and loading of KCl wt.% for Fisher-Tropsch synthesis (FTS). The results were showed that the catalyst containing 50 wt.% (Co/Fe)/SiO2 (Co/Fe ratio is 70/30) which promoted with 0.6 wt.% KCl is an optimal nano catalyst for conversion CO+H2 to a range of hydrocarbons especially light olefins. Also the results showed that optimal operating conditions for optimal nano catalyst are 250 °C, H2/CO molar ratio 2/1 under 1 bar of pressure. Characterization of catalyst precursors and calcined catalysts were done by different methods such as: powder X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 physisorption and thermal analysis methods such as thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC).
- انتشار مقاله: 18-09-1396
- نویسندگان: Mostafa Feyzi,Mohammad Joshaghani,Shirin Nadri
- مشاهده
- جایگاه : پژوهشی
- مجله: Physical Chemistry Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Artificial Neural Network,Adaptive neuro-fuzzy inference system,Kinematic viscosity,ultrasonic irradiation,residue fuel oil
- چکیده:
- چکیده انگلیسی: In the present work, the influences of temperature, solvent concentration and ultrasonic irradiation time were numerically analyzed on viscosity reduction of residue fuel oil (RFO). Ultrasonic irradiation was applied at power of 280 W and low frequency of 24 kHz. The main feature of this research is prediction and optimization of the kinematic viscosity data. The measured results of eighty-four samples, including 336 data points, were developed by artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS). The ANN predictions were also compared with the ANFIS approach by means of various descriptive statistical indicators, including absolute average deviation (AAD), average relative deviation (ARD) and coefficient of correlation (R2). The AAD and R2 of the developed ANN model for kinematic viscosity prediction of overall set were 0.0107 and 0.99384, respectively. On the other hand, for ANFIS approach, the AAD of 0.02112 and R2 of 0.99279 were attained. Although accuracy and precision of the ANN model were more than the ANFIS approach, it has been illustrated that the proposed ANN and ANFIS models have a superior performance with acceptable errors on the RFO kinematic viscosity estimation. Findings of this research clearly revealed that the neural network and neuro-fuzzy approaches could be successfully employed for prediction and optimization of kinematic viscosity of RFO and high viscosity materials in oil processes.
- انتشار مقاله: 18-10-1394
- نویسندگان: Akbar Mohammadi Doust,Masoud Rahimi,Mostafa Feyzi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Applied Research in Water and Wastewater
- نوع مقاله: Journal Article
- کلمات کلیدی: Magnetic nanoparticles,Preconcentration,Central composite design,Methyl Red,Removal
- چکیده:
- چکیده انگلیسی: A method was developed for removal, preconcentration and spectrophotometric determination of trace amounts of methyl red based on SiO2-coated Fe3O4magnetic nanoparticles. The influence of pH, dosage of adsorbent and contact time on the adsorption of dye was explored by central composite design. The kinetic data were analyzed based on the Langmuir and Freundlich adsorption isotherms. The Langmuir model was fitted well to data and the maximum monolayer capacity q max of 49.50 mg g−1 was calculated. The results showed that desorption efficiencies of higher than 99% can be achieved in a short contact time of 3 min and in one step elution using 2.0 mL of 0.1 mol L−1 NaOH. The magnetic nanoparticles were washed with deionized water and reused for two successive removal processes with removal efficiencies more than 90%. Then desorbed dye was determined spectrophotometrically. The calibration curve was linear in the range of 0.025–0.250 mg L−1 of dye with a correlation coefficient of 0.9922. The relative standard deviations obtained upon application of the method to the real samples were lower than 0.7%. A preconcentration factor of the method was 50.
- انتشار مقاله: 27-05-1392
- نویسندگان: Masoud Shariati-Rad,Mohsen Irandoust,Somayyeh Amri,Mostafa Feyzi,Fattaneh Ja’fari
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Catalysis
- نوع مقاله: Journal Article
- کلمات کلیدی: Biodiesel,Kinetics, Activation energy, Characterization, Operational conditions, Pseudo-second order
- چکیده:
- چکیده انگلیسی: In the present research work, the kinetics of sunflower oil transesterification reaction in the presence of Ba-Sr/ZSM-5 nanocatalyst which prepared using incipient wetness impregnation method was investigated. The 10wt.%Ba-Sr/ZSM-5 (Sr/Ba=3/2) nanocatalyst was calcined at 600 °C for 6 h with a heating rate of 3 ºC/min. The experimental conditions were the methanol/oil 9/1molar ratio, reaction time (0-180 min) and reaction temperature (323–333 K) with mechanical stirring of 500 rpm. An irreversible pseudo-second order kinetics was considered for triglyceride conversion from the best modeling of experimental data. From the kinetic study, Ea=67.03 kJ/mol and A=9.29×108 1/min were obtained. The yield of the methyl ester products (86.69%) were determined using gas chromatography–mass spectrometry. characterization of the catalysts and precursors was performed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-Ray diffraction (XRD), Transmission electron microscopy (TEM), and N2 adsorption-desorption measurement methods.
- انتشار مقاله: 15-03-1394
- نویسندگان: Mostafa Feyzi,Gelareh Khajavi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Characterization,: Biodiesel,Wetness impregnation,Calcination conditions,Operational condition
- چکیده:
- چکیده انگلیسی: The promoted K-La nanocatalysts supported on ZSM-5 zeolite were prepared via wetness impregnation method and tested for biodiesel production from soybean oil. The effects of different weight percentage of La, loading of K as a promoter and calcination conditions on structure and activity of catalyst were investigated. Results showed that the supported catalyst containing 7wt.% of La was promoted with 1wt.% of K is an optimal catalyst for biodiesel production. The best operational conditions were the CH3OH/oil=12/1 molar ratio at 60˚C with mechanical stirring 500 rpm for 3 h. The biodiesel yield reached 90% under the optimal operational conditions. It was found that K-La/ZSM-5 nanocatalyst have high basic sites and catalytic activity for biodiesel production. Characterization of catalysts was carried out by using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Temperature Programmed Desorption (TPD), X-Ray Diffraction (XRD), Fourier Transform-InfraRed(FT-IR) spectroscopy and N2 adsorption-desorption measurements methods.
- انتشار مقاله: 25-11-1394
- نویسندگان: Mostafa Feyzi,Ali Lorestani Zinatizadeh,Parasto Nouri,Fataneh Jafari
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Fischer-Tropsch synthesis,Co-impregnation,Operation Conditions,Catalytic performance
- چکیده:
- چکیده انگلیسی: A series of x(Co, Mn)/TiO2 catalysts (x=2–12wt.%) containing 25%Co and 75%Mn were prepared by the co-impregnation method. All prepared catalysts have been tested in Fischer-Tropsch synthesis for production of C2-C4 olefins. It was found that the catalyst containing 8wt.%(Co,Mn)/TiO2 is an optimal catalyst for production of C2-C4 olefins. The effect of operation conditions such as the H2/CO molar feed ratios, temperature, Gas Hourly Space Velocity (GHSV) and total reaction pressure on the catalytic performance of optimal catalyst was investigated. Characterizations of both precursors and catalysts were carried out using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET) specific surface area measurement, Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC).
- انتشار مقاله: 30-08-1388
- نویسندگان: Mostafa Feyzi,Ali Akbar Mirzaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Advances in Nanochemistry
- نوع مقاله: Journal Article
- کلمات کلیدی:
- چکیده:
- چکیده انگلیسی: In this report, the kinetic and equilibrium isotherm modeling for removal of malachite green dye with Fe3O4@SiO2-CPTS magnetic nanoparticles in aqueous solutions were investigated. The equilibrium adsorption data were fitted with Langmuir, Freundlich, Redlich-Peterson, Temkin and Dubinin-Radushkevich isotherm models. The adsorption equilibrium data fitted very well to Redlich-Peterson (D-R) isotherm models that predict accurately the adsorption experimental data on solid adsorbents in comparison to other models. Moreover, the adsorption kinetics data were fitted with the pseudo-second order model. Characterization of Fe3O4@SiO2-CPTS Magnetic nanoparticles was carried out by using scanning electron microscopy (SEM) and Fourier transform-infrared spectroscopy (FT-IR). The recovery tests were carried out to evaluate the reliability of the NPs for the adsorption and desorption of malachite green dye that showed excellent recoveries in both water solution at pH = 4 (recovery=95%).
- انتشار مقاله: 31-06-1397
- نویسندگان: Mostafa Feyzi,Leila Nourozi,Masoud Shariati-Rad,Fares Abdi
- مشاهده