Water samples of 0, 50, and 100 nephelometric turbidity units (NTU) spiked with fecal coliforms (... more Water samples of 0, 50, and 100 nephelometric turbidity units (NTU) spiked with fecal coliforms (107 CFU/ml) were exposed to natural sunshine in 1l quartz glass tubes fitted with rectors’ compound parabolic concentrators CPCS at two forms CPC1 (whit nanoparticle zinc oxide) and CPC2(without nanoparticle zinc oxide). The samples were characterized using the X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscope (TEM). On clear days, the complete inactivation times (more than 7-log unit reduction in bacterial population) in the systems with CPC1, and CPC2 were 15, and 30 min, respectively. The maximum temperatures obtained in the water samples were 80 for CPC1, and 82 for CPC2. The use of CPC1 with hydroxyl radicals (OH•) production significantly improved the efficiency of the old CPCS technique, since these systems (CPC1-2) shortened the exposure times to solar radiation and also minimized the negative effects of turbidity and also regrowth was zero in the disinfected samples. Due to two simultaneous effects of high temperatures and UV, regrowth in most ways of solar disinfection was not seen in these examples. Overall, this technology has been proved to be a good enhancement method to inactivate microorganisms under real conditions and represents a good alternative technique to drinking water treatment.
Nano-cellulose with high amount of free OH groups could be used as supporting agents for boron tr... more Nano-cellulose with high amount of free OH groups could be used as supporting agents for boron trifluoride (BF3). Nano-BF3/cellulose is a solid acid and a biodegradable catalyst which was prepared via reaction of nano-cellulose and BF3. The structure of this catalyst was studied by FT-IR, FESEM, TEM, XRD, EDS, TGA, XRF and BET. In this research, the synthesis of highly functionalized tetrahydropyridines has been developed via a five-component reaction of aldehyde, amine and ethyl acetoacetate using nano-BF3/cellulose under solvent-free conditions. The structures of obtained products were identified by FTIR, 1H NMR and 13C NMR. Some advantages of this protocol are high to good yields, environmentally benign procedure, easy work-up of reaction and moderate reusability of the catalyst.
In-situ synthesis of Ti-incorporated MCM-41 nano catalyst was carried out by the hydrothermal met... more In-situ synthesis of Ti-incorporated MCM-41 nano catalyst was carried out by the hydrothermal method to prepare a mesoporous catalyst for the oxidative desulfurization reaction (ODS). Oxidative reaction of dibenzothiophene (DBT) as a heavy sulfur compound was evaluated in a solution of n-decane as a model of liquid fuel. The synthesized catalysts were characterized by XRD, FESEM, EDX, TEM, FTIR and BET analysis and the most crystalized and purified catalyst on the base of XRD analysis was obtained at the synthesis temperature of 383 K, TIPT/TEOS=0.01, NaOH/TEOS=0.3 and TEOS/CTAB=0.2. The ODS reaction was investigated in a batch reactor in the presence of H2O2 as oxidant and the effect of operating conditions such as reaction temperature and molar ratio of oxidant/DBT were studied by the experimental design and the optimal operating conditions were predicted on the base of maximum DBT conversion. Removal of the produced sulfones was performed by acetonitrile as a polar solvent with the equal volume ratio of acetonitrile to model fuel. By simultaneous reaction and extraction, the DBT removal was achieved up to 99.5% during 20 min reaction. The recyclability of the prepared catalyst was studied by treatment with methanol and drying at 373 K for 4 hours. It was revealed that after two stages of reaction-regeneration, the conversion of DBT was reduced from 99.5 to 88%.
Synthesis of nickel oxide nanoparticles (NiO NPs) was carried out by Marrubium astranicum leaf ex... more Synthesis of nickel oxide nanoparticles (NiO NPs) was carried out by Marrubium astranicum leaf extract. The average of particle sizes for NiO NPs was 40 nm. NiO NPs modified carbon paste electrodes in the absence (CPE/NiO NPs) and the presence of sodium dodecyl sulfate (CPE/NiO NPs/SDS) were examined for the electrocatalytic oxidation of methanol in alkaline solutions. The cyclic voltammograms of modified electrodes showed the redox behavior of Ni(III)/Ni(II) couple. However, the presence of SDS at the surface of the electrode increased the efficiency of the catalyst. The values of charge transfer coefficients (α) for the CPE/NiO NPs and CPE/NiO NPs/SDS in the presence of methanol were estimated at about 0.63 and 0.84. Finally, the electrocatalytic oxidation of methanol at the surface of the CPE/NiO NPs/SDS was studied in the optimum conditions (30 min for immersion time in SDS solution, 0.01 M for SDS concentration and 0.4 M for methanol concentration).
In this work, the SBA-15-supported dithizone-copper(I) [SBA-15-dtz–Cu(I)] complex as a new hetero... more In this work, the SBA-15-supported dithizone-copper(I) [SBA-15-dtz–Cu(I)] complex as a new heterogeneous catalyst is prepared for the first time. The catalyst prepared is characterized by the FT-IR spectroscopy, SEM, and ICP techniques. This reusable heterogeneous catalyst can be used in the click reactions for the green and facile synthesis of 1,4-disubstituted 1,2,3-triazolesvia a one-pot three-component reaction of benzyl chloride derivatives, terminal alkynes, and sodium azide in the water at 60 °C. A synthetic technique offering numerous advantages including environmentally friendly, high-to-excellent reaction yields, operational simplicity, short reaction times, reusability of the catalyst, and lack of an organic solvent was developed.
Using hydrothermal synthesis process a series of Mobil Five (MFI) zeolites were synthesized with ... more Using hydrothermal synthesis process a series of Mobil Five (MFI) zeolites were synthesized with silica to alumina ratio (SAR) of 50, 100 and 200. The synthesized MFI zeolites were used to exchange with 0.5%, 1.0% and 2.0% Ca(NO 3) 2 solutions for modification of MFI zeolites to Ca-MFI zeolite. The formation of MFI zeolite phases was identified by XRD and FT-IR analysis. TGA studies reveal the thermal stability of the synthesized samples. The successful exchange of the parent samples with Ca was confirmed by UV-Vis (DR) spectra. The specific surface area, pore volume and pore size of the synthesized samples were investigated by the nitrogen adsorption-desorption isotherm. The morphology of the synthesized samples was examined using the scanning electron microscopy. O-methylation of phenol was carried over different synthesized catalysts to produce anisole as the major product.
Maryam Sadat Ghasemzadeh was born in Ghaen/ Southern Khorasan, Iran. She received her B.Sc. in Pu... more Maryam Sadat Ghasemzadeh was born in Ghaen/ Southern Khorasan, Iran. She received her B.Sc. in Pure Chemistry from Imam Khomeini International University and M.Sc. in Organic Chemistry from Birjand University under the supervision of Professor Sara Sobhani. She is currently studying her Ph.D. in Ferdowsi University of Mashhad under the supervision of Professor Batool Akhlaghinia. Her current research focuses on new heterogeneous nanocatalysts to develop new methods of organic synthesis.
The expeditious synthesis of 2-aryl-benzothia/(oxa)zoles was carried out by the condensation of 2... more The expeditious synthesis of 2-aryl-benzothia/(oxa)zoles was carried out by the condensation of 2-aminothiophenol/ 2-aminophenol and diverse aryl aldehydes in presence of Acacia concinna as a biocatalyst under microwave irradiation. The catalytic process is associated with excellent yields, greener reaction conditions and the environmentally friendly microwave technique which are the striking features of the present protocol.
Fe (III) supported graphitic carbon nitride nanocomposite was synthesized by impregnation of FeCl... more Fe (III) supported graphitic carbon nitride nanocomposite was synthesized by impregnation of FeCl3 with g-C3N4 (Fe (III) @ g-C3N4). Then, the synthesis of spirooxindole derivatives was carried out in the presence of Fe (III) @ graphitic carbon nitride nanocomposite via the multi-component reaction of malononitrile, isatins, and 1,3-dicarbonyl compounds in green media (ethanol/water (1:1)) under reflux conditions and the corresponding products were prepared in good to excellent yields (70-98 %). Also, the heterogeneous nanocatalyst was characterized by different techniques including the transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), atomic absorption spectroscopy (AAS) and X-ray diffraction (XRD). Furthermore, the nanocomposite is recoverable and reusable several times without a negligible decrease in its catalytic performance.
Nano-peanut shell-OSO 3 H nanoparticles were simply prepared and characterized by the scanning el... more Nano-peanut shell-OSO 3 H nanoparticles were simply prepared and characterized by the scanning electron microscopy (SEM), transmission electron microscope (TEM), fourier transform infrared (FT-IR), energy dispersive X-ray spectroscopy (EDX), and thermal analysis techniques (TGA/DTG). The catalytic activity of nano-peanut shell-OSO3H was studied in the synthesis of biologically important 4H-pyran derivatives. The reaction involves the use of Kojic acid, 5,5-dimethyl-1,3-cyclohexanedione, and various benzaldehydes. A wide range of benzaldehydes is compatible in this reaction, producing excellent yields in a short time. The successful synthesis of dihydropyrano[3,2-b]chromenedione derivatives shows that nano-peanut shell-OSO3H has high catalytic activity and can be effectively used as a green catalyst.
In this study, the activity of different transitional metals over modified H-ZSM-5 catalysts for ... more In this study, the activity of different transitional metals over modified H-ZSM-5 catalysts for methane conversion to aromatics was compared. The first group of catalysts was Mo-impregnated H-ZSM-5 zeolites with 1, 3 and 6 wt% of Mo. The second group was M (3 wt%)-impregnated H-ZSM-5 (M: Ag, Cd, Cr, Mo, Zn and Mn). The catalytic activity of the first group was investigated at temperature of 600, 700 and 800 ℃ and gas hourly space velocity (GHSV) of 1500, 2250, 3600 [ml.g-1 .h-1 ]. Likewise, the second group of catalysts was examined at 700 ℃ and GHSV of 2250 [ml.g-1 .h-1 ]. The catalyst samples were appropriately characterized by XRD, BET and SEM techniques. The effect of loaded transitional metals on the methane conversion was sorted on the basis of the benzene yield as follows: 3 %wt Mo> 3 %wt Zn> 3 %wt Mn> 3%wt Ag> 3%wt Cd > 3%wt Cr. The highest methane conversion was 11.13% obtained over the Mo (3 wt%)-impregnated HZSM-5 catalyst.
A suitable model for predicting the product quality of vacuum gas oil (VGO) catalytic hydrocracki... more A suitable model for predicting the product quality of vacuum gas oil (VGO) catalytic hydrocracking is developed. Data were obtained using an experimental catalytic hydrocracking reactor loaded with the Ni-Mo/Al2O3-SiO2 catalyst. A set of experimental runs was conducted under various operating temperatures from 380 to 450 ℃. Three distribution models were used to develop the predictive model. By the discrete lumping model, distillation curves of the cracked products (naphtha, kerosene, diesel, and gas) were obtained using the simulated distillation test. Model validation results showed that the proposed models are capable of predicting the distillation curves of the hydrocracked products accurately. Accuracy and simplicity of the developed model make it suitable to estimate the conversion and also the product distribution of hydrocracking units in refineries.
In the current survey, the removal of dye from contaminated water was studied by photocatalytic d... more In the current survey, the removal of dye from contaminated water was studied by photocatalytic degradation using TiO2 nanoparticles with respect to pH, TiO 2 dosage, reaction time, temperature and initial dye concentration. TiO 2 nanoparticles were investigated by XRD, FESEM and FT-IR. The RSM was chosen to study the composition effects of input independent factors and one dependent output response (removal efficiency). The P-value (2.2 × 10 −16), F-value (1832), R 2 (multiple R-squared: 0.9985, adjusted R-squared: 0.9972), and lack of fit (0.432) indicate that the reduced full second order model is highly significant for dye removal by TiO 2 nanoparticles. The maximum percentage removal of dye, 90.2%, was achieved at optimum operating conditions including pH=6.5, TiO2 dose (1.2 g L-1), contact time (67.5 min), temperature (40 °C), and dye concentrations (55 mg L-1)), respectively. The maximum removal efficiency was calculated to be 100%, using regression coefficients derived from the model and the Solver "Add-ins". The results indicated that the TiO 2 photocatalyst was very proper for the removal dye from contaminated water, and it had good efficiency in eliminating textile dyes.
A green, efficient, chemoselective, facile and clean procedure is described and discussed for the... more A green, efficient, chemoselective, facile and clean procedure is described and discussed for the synthesis of α, α'-bis (substituted-benzylidene) cycloalkanones in solvent-free conditions. The condensation reaction was carried out through the reaction of aromatic aldehydes with cycloalkanones in the presence of Fe 3 O 4 @WO 3 (Fe 3 O 4 @WO 3-EAE-SO 3 H (III)) nanoparticles as the catalyst. The nanostructured catalyst with the spherical shape, particle size in the range of 7-23 nm and superparamagnetic behavior may be referred as an excellent replacement for Brønsted acids. The reaction proceeds rapidly at room temperature, giving high yields of products. No self-condensation product was produced. Easy separation of the catalyst from the reaction mixture by means of an external magnetic field and re-using up to seven times without loss of activity are the salient features of the present method.
In this work, the photoelectrocatalytic (PEC) degradation of 2,5-dichlorophenol can be used for i... more In this work, the photoelectrocatalytic (PEC) degradation of 2,5-dichlorophenol can be used for its removal from aqueous solution. To study this activity, a TiO2 thin film modified titanium sheet (TiO2/Ti) was fabricated by anodizing Ti plates using a two electrode system under the constant bias voltage of 20 V for 20 min in a solution of 0.2% (v/v) HF followed by calcination at 500 o C for 2 h. Then, the electrochemical properties of 2,5-dichlorophenol were compared on the surface of the TiO 2 /Ti and unmodified Ti electrodes. Consequently, the TiO2/Ti was applied for PEC degradation of 2,5-dichlorophenol. It was found that 2,5-dichlorophenol could be degraded more efficiently by this photoelectrocatalysis process than the sum of degradation obtained by photocatalytic (PC) and electrochemical (EC) oxidation so that the amount of 2,5-dichlorophenol degraded by PEC, PC and EC oxidation were equal to 51%, 39% and 5% respectively under the 0.4 V voltage in 60 min. The effect of various parameters was studied and the highest degradation percentage of 2,5-dichlorophenol was obtained at pH 6.0, the initial 2,5-dichlorophenol concentration of 7.0 mg L-1 and applied potential of 1.2 V.
The surfaces of molybdenum carbide were varied by changing the carburization temperature between ... more The surfaces of molybdenum carbide were varied by changing the carburization temperature between 823 and 1123 K. The surfaces of the catalytic material were investigated using in-situ temperature program carburization followed by temperature program reduction and oxidation. In-situ temperature program oxidation (TPO) showed the surfaces of the catalysts contain a similar amount of carbonaceous deposit, while temperature program reduction (TPR) showed their ability to consume hydrogen in different amounts. The result shows the surface of the carbide at 823 K contained oxygen, while those carburized at higher temperature (≥ 923 K) were pure carbide. The catalysts tested for hydroisomerization of n-heptane and the catalyst with oxycarbide surface showed higher activity and iso-heptane selectivity. Hence, carburization temperature plays a crucial role in the formation of an active catalyst.
ZnO and 2% Fe doped ZnO photocatalytic nanomaterials were successfully synthesized by successive ... more ZnO and 2% Fe doped ZnO photocatalytic nanomaterials were successfully synthesized by successive ionic layer adsorption and the reaction (SILAR) method. The characterizations of these nanomaterials were carried out using XRD, SEM and EDX techniques. XRD study shows that the samples have a hexagonal wurtzite crystal structure, size of which is in the range 21-23 nm. SEM shows nanoflakes or nano flower-like morphology, while EDX reveals the compositional analysis. In this paper, we investigated photocatalytic degradation of an aqueous suspension of methyl orange (MO) dye as a model pollutant. Degradation of dye was monitored by the spectrophotometric method. The effects of various parameters such as pH, contact time, initial dye concentration and catalyst dose were studied. in optimized process, the maximum degradation obtained using ZnO was 88 % and that using Fe doped ZnO was 94 % at a pH value of 8. We have concluded that, compared to ZnO, the 2% Fe doped ZnO is a promising photocatalyst for degradation of MO.
In this study, Nitrogen doped TiO 2 photocatalysts were prepared by the sol gel method and physic... more In this study, Nitrogen doped TiO 2 photocatalysts were prepared by the sol gel method and physicochemical properties were characterized by X-ray diffraction (XRD), and scanning electron microscopy (SEM), photoluminescence, and energy dispersive X-ray spectroscopy (DRS) techniques. The XRD data indicated that the nanoparticles had the same crystals structures as the pure TiO2. Photocatalytic properties of the nitrogen doped TiO2 nanocatalyst and pure TiO2 were compared for degradation of Blue 5 dye in visible light irradiation and the DRS results showed that the band gap of doped photocatalyst was smaller than that of the undoped TiO 2 and there was a shift in the absorption band toward the visible light region. The Photocatalytic properties of the nitrogen doped TiO2 nanocatalyst were employed for degradation of crystal Blue 5 dye under visible light irradiation. The effects of pH, amount of photocatalysts, catalyst dosage, and dye concentration were also examined. The best results were reported for the concentration of 20 mg/L N-TiO 2 nano-particles. Also results showed that the photodecomposition of N-TiO 2 is complete at pH 11. Total organic carbon (TOC) analysis indicated 30 % mineralization of Blue 5 after 75 min irradiation.
This research describes application of a mesoporous nanostructured material based on basic ionic ... more This research describes application of a mesoporous nanostructured material based on basic ionic liquid anchored to silica, i.e. nano-2-(dimethylamino)-N-(silica-n-propyl)-N,N-dimethylethanaminium chloride {nano-[DMSPDE][Cl]}, as a highly effective and heterogeneous nanocatalyst for the production of 2-amino-4H-chromenes. The one-pot multi-component reaction of aromatic aldehydes with malononitrile and 1-naphthol in the presence of nano-[DMSPDE][Cl] under solvent-free conditions affords the title compounds with high yields in short times.
Water samples of 0, 50, and 100 nephelometric turbidity units (NTU) spiked with fecal coliforms (... more Water samples of 0, 50, and 100 nephelometric turbidity units (NTU) spiked with fecal coliforms (107 CFU/ml) were exposed to natural sunshine in 1l quartz glass tubes fitted with rectors’ compound parabolic concentrators CPCS at two forms CPC1 (whit nanoparticle zinc oxide) and CPC2(without nanoparticle zinc oxide). The samples were characterized using the X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscope (TEM). On clear days, the complete inactivation times (more than 7-log unit reduction in bacterial population) in the systems with CPC1, and CPC2 were 15, and 30 min, respectively. The maximum temperatures obtained in the water samples were 80 for CPC1, and 82 for CPC2. The use of CPC1 with hydroxyl radicals (OH•) production significantly improved the efficiency of the old CPCS technique, since these systems (CPC1-2) shortened the exposure times to solar radiation and also minimized the negative effects of turbidity and also regrowth was zero in the disinfected samples. Due to two simultaneous effects of high temperatures and UV, regrowth in most ways of solar disinfection was not seen in these examples. Overall, this technology has been proved to be a good enhancement method to inactivate microorganisms under real conditions and represents a good alternative technique to drinking water treatment.
Nano-cellulose with high amount of free OH groups could be used as supporting agents for boron tr... more Nano-cellulose with high amount of free OH groups could be used as supporting agents for boron trifluoride (BF3). Nano-BF3/cellulose is a solid acid and a biodegradable catalyst which was prepared via reaction of nano-cellulose and BF3. The structure of this catalyst was studied by FT-IR, FESEM, TEM, XRD, EDS, TGA, XRF and BET. In this research, the synthesis of highly functionalized tetrahydropyridines has been developed via a five-component reaction of aldehyde, amine and ethyl acetoacetate using nano-BF3/cellulose under solvent-free conditions. The structures of obtained products were identified by FTIR, 1H NMR and 13C NMR. Some advantages of this protocol are high to good yields, environmentally benign procedure, easy work-up of reaction and moderate reusability of the catalyst.
In-situ synthesis of Ti-incorporated MCM-41 nano catalyst was carried out by the hydrothermal met... more In-situ synthesis of Ti-incorporated MCM-41 nano catalyst was carried out by the hydrothermal method to prepare a mesoporous catalyst for the oxidative desulfurization reaction (ODS). Oxidative reaction of dibenzothiophene (DBT) as a heavy sulfur compound was evaluated in a solution of n-decane as a model of liquid fuel. The synthesized catalysts were characterized by XRD, FESEM, EDX, TEM, FTIR and BET analysis and the most crystalized and purified catalyst on the base of XRD analysis was obtained at the synthesis temperature of 383 K, TIPT/TEOS=0.01, NaOH/TEOS=0.3 and TEOS/CTAB=0.2. The ODS reaction was investigated in a batch reactor in the presence of H2O2 as oxidant and the effect of operating conditions such as reaction temperature and molar ratio of oxidant/DBT were studied by the experimental design and the optimal operating conditions were predicted on the base of maximum DBT conversion. Removal of the produced sulfones was performed by acetonitrile as a polar solvent with the equal volume ratio of acetonitrile to model fuel. By simultaneous reaction and extraction, the DBT removal was achieved up to 99.5% during 20 min reaction. The recyclability of the prepared catalyst was studied by treatment with methanol and drying at 373 K for 4 hours. It was revealed that after two stages of reaction-regeneration, the conversion of DBT was reduced from 99.5 to 88%.
Synthesis of nickel oxide nanoparticles (NiO NPs) was carried out by Marrubium astranicum leaf ex... more Synthesis of nickel oxide nanoparticles (NiO NPs) was carried out by Marrubium astranicum leaf extract. The average of particle sizes for NiO NPs was 40 nm. NiO NPs modified carbon paste electrodes in the absence (CPE/NiO NPs) and the presence of sodium dodecyl sulfate (CPE/NiO NPs/SDS) were examined for the electrocatalytic oxidation of methanol in alkaline solutions. The cyclic voltammograms of modified electrodes showed the redox behavior of Ni(III)/Ni(II) couple. However, the presence of SDS at the surface of the electrode increased the efficiency of the catalyst. The values of charge transfer coefficients (α) for the CPE/NiO NPs and CPE/NiO NPs/SDS in the presence of methanol were estimated at about 0.63 and 0.84. Finally, the electrocatalytic oxidation of methanol at the surface of the CPE/NiO NPs/SDS was studied in the optimum conditions (30 min for immersion time in SDS solution, 0.01 M for SDS concentration and 0.4 M for methanol concentration).
In this work, the SBA-15-supported dithizone-copper(I) [SBA-15-dtz–Cu(I)] complex as a new hetero... more In this work, the SBA-15-supported dithizone-copper(I) [SBA-15-dtz–Cu(I)] complex as a new heterogeneous catalyst is prepared for the first time. The catalyst prepared is characterized by the FT-IR spectroscopy, SEM, and ICP techniques. This reusable heterogeneous catalyst can be used in the click reactions for the green and facile synthesis of 1,4-disubstituted 1,2,3-triazolesvia a one-pot three-component reaction of benzyl chloride derivatives, terminal alkynes, and sodium azide in the water at 60 °C. A synthetic technique offering numerous advantages including environmentally friendly, high-to-excellent reaction yields, operational simplicity, short reaction times, reusability of the catalyst, and lack of an organic solvent was developed.
Using hydrothermal synthesis process a series of Mobil Five (MFI) zeolites were synthesized with ... more Using hydrothermal synthesis process a series of Mobil Five (MFI) zeolites were synthesized with silica to alumina ratio (SAR) of 50, 100 and 200. The synthesized MFI zeolites were used to exchange with 0.5%, 1.0% and 2.0% Ca(NO 3) 2 solutions for modification of MFI zeolites to Ca-MFI zeolite. The formation of MFI zeolite phases was identified by XRD and FT-IR analysis. TGA studies reveal the thermal stability of the synthesized samples. The successful exchange of the parent samples with Ca was confirmed by UV-Vis (DR) spectra. The specific surface area, pore volume and pore size of the synthesized samples were investigated by the nitrogen adsorption-desorption isotherm. The morphology of the synthesized samples was examined using the scanning electron microscopy. O-methylation of phenol was carried over different synthesized catalysts to produce anisole as the major product.
Maryam Sadat Ghasemzadeh was born in Ghaen/ Southern Khorasan, Iran. She received her B.Sc. in Pu... more Maryam Sadat Ghasemzadeh was born in Ghaen/ Southern Khorasan, Iran. She received her B.Sc. in Pure Chemistry from Imam Khomeini International University and M.Sc. in Organic Chemistry from Birjand University under the supervision of Professor Sara Sobhani. She is currently studying her Ph.D. in Ferdowsi University of Mashhad under the supervision of Professor Batool Akhlaghinia. Her current research focuses on new heterogeneous nanocatalysts to develop new methods of organic synthesis.
The expeditious synthesis of 2-aryl-benzothia/(oxa)zoles was carried out by the condensation of 2... more The expeditious synthesis of 2-aryl-benzothia/(oxa)zoles was carried out by the condensation of 2-aminothiophenol/ 2-aminophenol and diverse aryl aldehydes in presence of Acacia concinna as a biocatalyst under microwave irradiation. The catalytic process is associated with excellent yields, greener reaction conditions and the environmentally friendly microwave technique which are the striking features of the present protocol.
Fe (III) supported graphitic carbon nitride nanocomposite was synthesized by impregnation of FeCl... more Fe (III) supported graphitic carbon nitride nanocomposite was synthesized by impregnation of FeCl3 with g-C3N4 (Fe (III) @ g-C3N4). Then, the synthesis of spirooxindole derivatives was carried out in the presence of Fe (III) @ graphitic carbon nitride nanocomposite via the multi-component reaction of malononitrile, isatins, and 1,3-dicarbonyl compounds in green media (ethanol/water (1:1)) under reflux conditions and the corresponding products were prepared in good to excellent yields (70-98 %). Also, the heterogeneous nanocatalyst was characterized by different techniques including the transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), atomic absorption spectroscopy (AAS) and X-ray diffraction (XRD). Furthermore, the nanocomposite is recoverable and reusable several times without a negligible decrease in its catalytic performance.
Nano-peanut shell-OSO 3 H nanoparticles were simply prepared and characterized by the scanning el... more Nano-peanut shell-OSO 3 H nanoparticles were simply prepared and characterized by the scanning electron microscopy (SEM), transmission electron microscope (TEM), fourier transform infrared (FT-IR), energy dispersive X-ray spectroscopy (EDX), and thermal analysis techniques (TGA/DTG). The catalytic activity of nano-peanut shell-OSO3H was studied in the synthesis of biologically important 4H-pyran derivatives. The reaction involves the use of Kojic acid, 5,5-dimethyl-1,3-cyclohexanedione, and various benzaldehydes. A wide range of benzaldehydes is compatible in this reaction, producing excellent yields in a short time. The successful synthesis of dihydropyrano[3,2-b]chromenedione derivatives shows that nano-peanut shell-OSO3H has high catalytic activity and can be effectively used as a green catalyst.
In this study, the activity of different transitional metals over modified H-ZSM-5 catalysts for ... more In this study, the activity of different transitional metals over modified H-ZSM-5 catalysts for methane conversion to aromatics was compared. The first group of catalysts was Mo-impregnated H-ZSM-5 zeolites with 1, 3 and 6 wt% of Mo. The second group was M (3 wt%)-impregnated H-ZSM-5 (M: Ag, Cd, Cr, Mo, Zn and Mn). The catalytic activity of the first group was investigated at temperature of 600, 700 and 800 ℃ and gas hourly space velocity (GHSV) of 1500, 2250, 3600 [ml.g-1 .h-1 ]. Likewise, the second group of catalysts was examined at 700 ℃ and GHSV of 2250 [ml.g-1 .h-1 ]. The catalyst samples were appropriately characterized by XRD, BET and SEM techniques. The effect of loaded transitional metals on the methane conversion was sorted on the basis of the benzene yield as follows: 3 %wt Mo> 3 %wt Zn> 3 %wt Mn> 3%wt Ag> 3%wt Cd > 3%wt Cr. The highest methane conversion was 11.13% obtained over the Mo (3 wt%)-impregnated HZSM-5 catalyst.
A suitable model for predicting the product quality of vacuum gas oil (VGO) catalytic hydrocracki... more A suitable model for predicting the product quality of vacuum gas oil (VGO) catalytic hydrocracking is developed. Data were obtained using an experimental catalytic hydrocracking reactor loaded with the Ni-Mo/Al2O3-SiO2 catalyst. A set of experimental runs was conducted under various operating temperatures from 380 to 450 ℃. Three distribution models were used to develop the predictive model. By the discrete lumping model, distillation curves of the cracked products (naphtha, kerosene, diesel, and gas) were obtained using the simulated distillation test. Model validation results showed that the proposed models are capable of predicting the distillation curves of the hydrocracked products accurately. Accuracy and simplicity of the developed model make it suitable to estimate the conversion and also the product distribution of hydrocracking units in refineries.
In the current survey, the removal of dye from contaminated water was studied by photocatalytic d... more In the current survey, the removal of dye from contaminated water was studied by photocatalytic degradation using TiO2 nanoparticles with respect to pH, TiO 2 dosage, reaction time, temperature and initial dye concentration. TiO 2 nanoparticles were investigated by XRD, FESEM and FT-IR. The RSM was chosen to study the composition effects of input independent factors and one dependent output response (removal efficiency). The P-value (2.2 × 10 −16), F-value (1832), R 2 (multiple R-squared: 0.9985, adjusted R-squared: 0.9972), and lack of fit (0.432) indicate that the reduced full second order model is highly significant for dye removal by TiO 2 nanoparticles. The maximum percentage removal of dye, 90.2%, was achieved at optimum operating conditions including pH=6.5, TiO2 dose (1.2 g L-1), contact time (67.5 min), temperature (40 °C), and dye concentrations (55 mg L-1)), respectively. The maximum removal efficiency was calculated to be 100%, using regression coefficients derived from the model and the Solver "Add-ins". The results indicated that the TiO 2 photocatalyst was very proper for the removal dye from contaminated water, and it had good efficiency in eliminating textile dyes.
A green, efficient, chemoselective, facile and clean procedure is described and discussed for the... more A green, efficient, chemoselective, facile and clean procedure is described and discussed for the synthesis of α, α'-bis (substituted-benzylidene) cycloalkanones in solvent-free conditions. The condensation reaction was carried out through the reaction of aromatic aldehydes with cycloalkanones in the presence of Fe 3 O 4 @WO 3 (Fe 3 O 4 @WO 3-EAE-SO 3 H (III)) nanoparticles as the catalyst. The nanostructured catalyst with the spherical shape, particle size in the range of 7-23 nm and superparamagnetic behavior may be referred as an excellent replacement for Brønsted acids. The reaction proceeds rapidly at room temperature, giving high yields of products. No self-condensation product was produced. Easy separation of the catalyst from the reaction mixture by means of an external magnetic field and re-using up to seven times without loss of activity are the salient features of the present method.
In this work, the photoelectrocatalytic (PEC) degradation of 2,5-dichlorophenol can be used for i... more In this work, the photoelectrocatalytic (PEC) degradation of 2,5-dichlorophenol can be used for its removal from aqueous solution. To study this activity, a TiO2 thin film modified titanium sheet (TiO2/Ti) was fabricated by anodizing Ti plates using a two electrode system under the constant bias voltage of 20 V for 20 min in a solution of 0.2% (v/v) HF followed by calcination at 500 o C for 2 h. Then, the electrochemical properties of 2,5-dichlorophenol were compared on the surface of the TiO 2 /Ti and unmodified Ti electrodes. Consequently, the TiO2/Ti was applied for PEC degradation of 2,5-dichlorophenol. It was found that 2,5-dichlorophenol could be degraded more efficiently by this photoelectrocatalysis process than the sum of degradation obtained by photocatalytic (PC) and electrochemical (EC) oxidation so that the amount of 2,5-dichlorophenol degraded by PEC, PC and EC oxidation were equal to 51%, 39% and 5% respectively under the 0.4 V voltage in 60 min. The effect of various parameters was studied and the highest degradation percentage of 2,5-dichlorophenol was obtained at pH 6.0, the initial 2,5-dichlorophenol concentration of 7.0 mg L-1 and applied potential of 1.2 V.
The surfaces of molybdenum carbide were varied by changing the carburization temperature between ... more The surfaces of molybdenum carbide were varied by changing the carburization temperature between 823 and 1123 K. The surfaces of the catalytic material were investigated using in-situ temperature program carburization followed by temperature program reduction and oxidation. In-situ temperature program oxidation (TPO) showed the surfaces of the catalysts contain a similar amount of carbonaceous deposit, while temperature program reduction (TPR) showed their ability to consume hydrogen in different amounts. The result shows the surface of the carbide at 823 K contained oxygen, while those carburized at higher temperature (≥ 923 K) were pure carbide. The catalysts tested for hydroisomerization of n-heptane and the catalyst with oxycarbide surface showed higher activity and iso-heptane selectivity. Hence, carburization temperature plays a crucial role in the formation of an active catalyst.
ZnO and 2% Fe doped ZnO photocatalytic nanomaterials were successfully synthesized by successive ... more ZnO and 2% Fe doped ZnO photocatalytic nanomaterials were successfully synthesized by successive ionic layer adsorption and the reaction (SILAR) method. The characterizations of these nanomaterials were carried out using XRD, SEM and EDX techniques. XRD study shows that the samples have a hexagonal wurtzite crystal structure, size of which is in the range 21-23 nm. SEM shows nanoflakes or nano flower-like morphology, while EDX reveals the compositional analysis. In this paper, we investigated photocatalytic degradation of an aqueous suspension of methyl orange (MO) dye as a model pollutant. Degradation of dye was monitored by the spectrophotometric method. The effects of various parameters such as pH, contact time, initial dye concentration and catalyst dose were studied. in optimized process, the maximum degradation obtained using ZnO was 88 % and that using Fe doped ZnO was 94 % at a pH value of 8. We have concluded that, compared to ZnO, the 2% Fe doped ZnO is a promising photocatalyst for degradation of MO.
In this study, Nitrogen doped TiO 2 photocatalysts were prepared by the sol gel method and physic... more In this study, Nitrogen doped TiO 2 photocatalysts were prepared by the sol gel method and physicochemical properties were characterized by X-ray diffraction (XRD), and scanning electron microscopy (SEM), photoluminescence, and energy dispersive X-ray spectroscopy (DRS) techniques. The XRD data indicated that the nanoparticles had the same crystals structures as the pure TiO2. Photocatalytic properties of the nitrogen doped TiO2 nanocatalyst and pure TiO2 were compared for degradation of Blue 5 dye in visible light irradiation and the DRS results showed that the band gap of doped photocatalyst was smaller than that of the undoped TiO 2 and there was a shift in the absorption band toward the visible light region. The Photocatalytic properties of the nitrogen doped TiO2 nanocatalyst were employed for degradation of crystal Blue 5 dye under visible light irradiation. The effects of pH, amount of photocatalysts, catalyst dosage, and dye concentration were also examined. The best results were reported for the concentration of 20 mg/L N-TiO 2 nano-particles. Also results showed that the photodecomposition of N-TiO 2 is complete at pH 11. Total organic carbon (TOC) analysis indicated 30 % mineralization of Blue 5 after 75 min irradiation.
This research describes application of a mesoporous nanostructured material based on basic ionic ... more This research describes application of a mesoporous nanostructured material based on basic ionic liquid anchored to silica, i.e. nano-2-(dimethylamino)-N-(silica-n-propyl)-N,N-dimethylethanaminium chloride {nano-[DMSPDE][Cl]}, as a highly effective and heterogeneous nanocatalyst for the production of 2-amino-4H-chromenes. The one-pot multi-component reaction of aromatic aldehydes with malononitrile and 1-naphthol in the presence of nano-[DMSPDE][Cl] under solvent-free conditions affords the title compounds with high yields in short times.
Uploads
Papers by Iranian J Catalysis