Synthetic organic pigments from the direct discharge of textile effluents are considered as colos... more Synthetic organic pigments from the direct discharge of textile effluents are considered as colossal global concern and attract the attention of scholars. The efficient construction of heterojunction systems involving precious metal co-catalysis is an effective strategy for obtaining highly efficient photocatalytic materials. Herein, we report the construction of a Pt-doped BiFeO3/O-g-C3N4 (Pt@BFO/O-CN) S-scheme heterojunction system for photocatalytic degradation of aqueous rhodamine B (RhB) under visible-light irradiation. The photocatalytic performances of Pt@BFO/O-CN and BFO/O-CN composites and pristine BiFeO3 and O-g-C3N4 were compared, and the photocatalytic process of the Pt@BFO/O-CN system was optimized. The results exhibit that the S-scheme Pt@BFO/O-CN heterojunction has superior photocatalytic performance compared to its fellow catalysts, which is due to the asymmetric nature of the as-constructed heterojunction. The as-constructed Pt@BFO/O-CN heterojunction reveals high p...
Synthetic organic pigments like xanthene and azo dyes from the direct discharge of textile efflue... more Synthetic organic pigments like xanthene and azo dyes from the direct discharge of textile effluents are considered colossal global issues and attract the concern of scholars. Photocatalysis continues to be a very valuable pollution control method for industrial wastewater. Incorporations of metal oxide catalysts such as zinc oxide (ZnO) on mesoporous Santa Barbara Armophous-15 (SBA-15) support to improve catalyst thermo-mechanical stability have been comprehensively reported. However, charge separation efficiency and light absorption of ZnO/SBA-15 continue to be limiting its photocatalytic activity. Herein, we report a successful preparation of Ruthenium-induced ZnO/SBA-15 composite via conventional incipient wetness impregnation technique with the aim of boosting the photocatalytic activity of the incorporated ZnO. Physicochemical properties of the SBA-15 support, ZnO/SBA-15, and Ru-ZnO/SBA-15 composites were characterized by X-ray diffraction (XRD), N2 physisorption isotherms at ...
A sol–gel synthesis technique was employed for the preparation of anatase phase {001}-TiO2/Au hyb... more A sol–gel synthesis technique was employed for the preparation of anatase phase {001}-TiO2/Au hybrid nanocomposites (NCs). The scalable, schematic, and cost-efficient method was successfully modified using HF and NH4OH capping agents. The photocatalytic activity of the as-synthesized {001}-TiO2/Au NCs were tested over 2-cycle degradation of methylene blue (MB) dye and pharmaceutical active compounds (PhACs) of ibuprofen and naproxen under direct sunlight illumination at 35 °C and 44,000 lx. Transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM), fast Fourier transform (FFT), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), and ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS) were employed for the characterization of the as-prepared sample. The characterization results from the TEM, XPS, and XRD studies established both the distribution of Au colloids on the surface...
Presence of moisture is very important for vegetable oils and for corresponding biodiesel because... more Presence of moisture is very important for vegetable oils and for corresponding biodiesel because it may cause some problems or accelerate some issues that cannot be ignored. One of the main hindrances of biodiesel is its hygroscopic nature, which accelerates the corrosion of the fuel system of the engines. Thus, this study aims to investigate the effects of moisture on corn biodiesel and its susceptibility to corrosion on different automotive materials such as copper and mild carbon steel. Static immersion tests in corn biodiesel (B100) with different water concentrations (100 ppm, 500 ppm, and 700 ppm) were carried out at 90°C for 1200 h, and the results were compared to that of commercial diesel fuel (B0). After immersion tests, the surface morphology was studied by scanning electron microscopy (SEM), and corrosion products were detected by X-ray diffraction (XRD). The total acid number (TAN) was used to evaluate the changes in acidity of fuel, before and after immersion tests. I...
The aim of this paper was to evaluate the behavior of Pd/SBA-15 catalyst for steam reforming of b... more The aim of this paper was to evaluate the behavior of Pd/SBA-15 catalyst for steam reforming of bio-ethanol. Bioethanol was obtained by alcoholic fermentation of different sweet fruits and the alcohol content is in the range of 5–15 %v/v. The Pd/SBA-15 catalyst was prepared using pore volume impregnation method and characterized by several techniques as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and N2 adsorption/desorption isotherms. The catalytic test showed that Pd/SBA-15 catalyst is able to perform higher ethanol conversion and hydrogen yield in a quit low temperature range (573-773 K).
Polyethylene terephthalate (PET) is one of the most widely used materials for food packaging and ... more Polyethylene terephthalate (PET) is one of the most widely used materials for food packaging and fishing nets. After use it become waste and, due to poor collection, most will be found floating in marine waters. This paper presents the results of a study of PET depolymerization by hydrolysis. We observed that marine water is a perfect reactant because it contains a multitude of metal ions that act as catalysts. A first-order kinetic model was developed and experimental data fitted to it. An activation energy of 73.5 kJ/mole and a pre-exponential factor of 5.33 × 107 h–1 were obtained. Considering that the global ocean is a huge batch reactor operating under isothermal conditions, the solution of the mathematical model shows that in tropical regions only 72 years is needed for total and only 4.5 years for 50% PET conversion.
Biodiesel plays an important role in reducing the dependency of petroleum fuels and reduce enviro... more Biodiesel plays an important role in reducing the dependency of petroleum fuels and reduce environmental pollution. Biodiesel has attracted attention as a renewable, non-toxic, and biodegradable fuel. In the past years, researchers have expanded their work to new methods of obtaining biodiesel. In this work, biodiesel production using soybean oil from the industry is described. Biodiesel was further analyzed and compared with the EN biodiesel specifications. The characterization of biodiesel was performed in order to obtain density, viscosity and flash point. Moreover, the study was focused in optimized the biodiesel yield, obtain from soybean oil using Artificial Neural Networks (ANN). The variable parameters were molar ratio between methanol and oil, reaction temperature and catalyst quantity. The paper concludes that the ANN can be successfully used to optimize the biodiesel yield.
Artificial neural network ANN is an appropriate tool for predestining the different relationships... more Artificial neural network ANN is an appropriate tool for predestining the different relationships across many scientific researches. Air emissions prediction is an effective method of securing public health by revealing the imminent danger of air pollutants. So far, the existing methods of air emissions concentration prediction became useless on long-term dependencies, and most neglect spatial correlations. In this study, an artificial neural network model, which also takes into account the spatial-temporal variable, is proposed for prediction of air emission. The ANN was used in order to take into account the historical data, auxiliary data such as environmental quality and weather conditions. Evaluation of the results revealed that the developed ANN model appears to be an appropriate tool in predicting environmental air emissions. The data were collected from 12 air quality-monitoring stations from a random county in Romania. The proposed model performed well and presented a relat...
We herein report on the synthesis by a facile sol-gel method without templates for preparing ruti... more We herein report on the synthesis by a facile sol-gel method without templates for preparing rutile RuxTi1-xO2 (x = 0.16; 0.07; 0.01) nanobelts with exposed (001) facets. The rutile nanobelts with exposure (001) facets, favor the separation photogenerated electron-hole pairs and inhibit the recombination of the electron-hole pairs resulting in the increase of the number of main superoxide and hydroxyl radicals. The photocatalytic properties of the rutile RuxTi1-xO2 nanobelts were evaluated by discoloring of MB (methylene blue) dye under sunlight irradiation at an intensity of 40000 lx. It was also done a thorough interface analysis to determine the band energy.
A series of solid acid catalyst of the Keggin-type 12-phosphotungstic acid, H3PW12O40, supported ... more A series of solid acid catalyst of the Keggin-type 12-phosphotungstic acid, H3PW12O40, supported on ordered mesoporous silica MCM-41 were prepared by a simple and effective impregnation method. MCM-41 supports were synthesized in a relatively short time via a recently reported ultrasonic irradiation method. The synthesis sonication time has been systematically varied in order to investigate its influence on the structural order of the resulting materials. The prepared catalysts were characterized by nitrogen adsorption, X-ray diffraction, Raman spectroscopy and thermogravimetric analysis. The resulting materials exhibited hexagonally ordered meso structure, with high surface area of the order of several hundreds of m2g-1,relatively large pore volumes, with the pore diameter in the range of 2.19 to 2.41 nm and a corresponding pore wall thickness of over 1.67nm. The results have demonstrated that high quality MCM-41 materials can be synthesized via the ultrasonic irradiation in few te...
A Co/CeO2 catalyst for ethanol steam reforming process was prepared and characterized using diffe... more A Co/CeO2 catalyst for ethanol steam reforming process was prepared and characterized using different characterization techniques including X-ray diffraction, UV-Vis diffuse reflectance, FTIR spectroscopy, scanning electron microscopy (SEM), N2 adsorption/desorption isotherms (BET) and thermal analysis method (TGA). The catalytic test in ethanol steam reforming process showed a high H2 yield and almost complete ethanol conversion.
Synthetic organic pigments from the direct discharge of textile effluents are considered as colos... more Synthetic organic pigments from the direct discharge of textile effluents are considered as colossal global concern and attract the attention of scholars. The efficient construction of heterojunction systems involving precious metal co-catalysis is an effective strategy for obtaining highly efficient photocatalytic materials. Herein, we report the construction of a Pt-doped BiFeO3/O-g-C3N4 (Pt@BFO/O-CN) S-scheme heterojunction system for photocatalytic degradation of aqueous rhodamine B (RhB) under visible-light irradiation. The photocatalytic performances of Pt@BFO/O-CN and BFO/O-CN composites and pristine BiFeO3 and O-g-C3N4 were compared, and the photocatalytic process of the Pt@BFO/O-CN system was optimized. The results exhibit that the S-scheme Pt@BFO/O-CN heterojunction has superior photocatalytic performance compared to its fellow catalysts, which is due to the asymmetric nature of the as-constructed heterojunction. The as-constructed Pt@BFO/O-CN heterojunction reveals high p...
Synthetic organic pigments like xanthene and azo dyes from the direct discharge of textile efflue... more Synthetic organic pigments like xanthene and azo dyes from the direct discharge of textile effluents are considered colossal global issues and attract the concern of scholars. Photocatalysis continues to be a very valuable pollution control method for industrial wastewater. Incorporations of metal oxide catalysts such as zinc oxide (ZnO) on mesoporous Santa Barbara Armophous-15 (SBA-15) support to improve catalyst thermo-mechanical stability have been comprehensively reported. However, charge separation efficiency and light absorption of ZnO/SBA-15 continue to be limiting its photocatalytic activity. Herein, we report a successful preparation of Ruthenium-induced ZnO/SBA-15 composite via conventional incipient wetness impregnation technique with the aim of boosting the photocatalytic activity of the incorporated ZnO. Physicochemical properties of the SBA-15 support, ZnO/SBA-15, and Ru-ZnO/SBA-15 composites were characterized by X-ray diffraction (XRD), N2 physisorption isotherms at ...
A sol–gel synthesis technique was employed for the preparation of anatase phase {001}-TiO2/Au hyb... more A sol–gel synthesis technique was employed for the preparation of anatase phase {001}-TiO2/Au hybrid nanocomposites (NCs). The scalable, schematic, and cost-efficient method was successfully modified using HF and NH4OH capping agents. The photocatalytic activity of the as-synthesized {001}-TiO2/Au NCs were tested over 2-cycle degradation of methylene blue (MB) dye and pharmaceutical active compounds (PhACs) of ibuprofen and naproxen under direct sunlight illumination at 35 °C and 44,000 lx. Transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM), fast Fourier transform (FFT), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), and ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS) were employed for the characterization of the as-prepared sample. The characterization results from the TEM, XPS, and XRD studies established both the distribution of Au colloids on the surface...
Presence of moisture is very important for vegetable oils and for corresponding biodiesel because... more Presence of moisture is very important for vegetable oils and for corresponding biodiesel because it may cause some problems or accelerate some issues that cannot be ignored. One of the main hindrances of biodiesel is its hygroscopic nature, which accelerates the corrosion of the fuel system of the engines. Thus, this study aims to investigate the effects of moisture on corn biodiesel and its susceptibility to corrosion on different automotive materials such as copper and mild carbon steel. Static immersion tests in corn biodiesel (B100) with different water concentrations (100 ppm, 500 ppm, and 700 ppm) were carried out at 90°C for 1200 h, and the results were compared to that of commercial diesel fuel (B0). After immersion tests, the surface morphology was studied by scanning electron microscopy (SEM), and corrosion products were detected by X-ray diffraction (XRD). The total acid number (TAN) was used to evaluate the changes in acidity of fuel, before and after immersion tests. I...
The aim of this paper was to evaluate the behavior of Pd/SBA-15 catalyst for steam reforming of b... more The aim of this paper was to evaluate the behavior of Pd/SBA-15 catalyst for steam reforming of bio-ethanol. Bioethanol was obtained by alcoholic fermentation of different sweet fruits and the alcohol content is in the range of 5–15 %v/v. The Pd/SBA-15 catalyst was prepared using pore volume impregnation method and characterized by several techniques as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and N2 adsorption/desorption isotherms. The catalytic test showed that Pd/SBA-15 catalyst is able to perform higher ethanol conversion and hydrogen yield in a quit low temperature range (573-773 K).
Polyethylene terephthalate (PET) is one of the most widely used materials for food packaging and ... more Polyethylene terephthalate (PET) is one of the most widely used materials for food packaging and fishing nets. After use it become waste and, due to poor collection, most will be found floating in marine waters. This paper presents the results of a study of PET depolymerization by hydrolysis. We observed that marine water is a perfect reactant because it contains a multitude of metal ions that act as catalysts. A first-order kinetic model was developed and experimental data fitted to it. An activation energy of 73.5 kJ/mole and a pre-exponential factor of 5.33 × 107 h–1 were obtained. Considering that the global ocean is a huge batch reactor operating under isothermal conditions, the solution of the mathematical model shows that in tropical regions only 72 years is needed for total and only 4.5 years for 50% PET conversion.
Biodiesel plays an important role in reducing the dependency of petroleum fuels and reduce enviro... more Biodiesel plays an important role in reducing the dependency of petroleum fuels and reduce environmental pollution. Biodiesel has attracted attention as a renewable, non-toxic, and biodegradable fuel. In the past years, researchers have expanded their work to new methods of obtaining biodiesel. In this work, biodiesel production using soybean oil from the industry is described. Biodiesel was further analyzed and compared with the EN biodiesel specifications. The characterization of biodiesel was performed in order to obtain density, viscosity and flash point. Moreover, the study was focused in optimized the biodiesel yield, obtain from soybean oil using Artificial Neural Networks (ANN). The variable parameters were molar ratio between methanol and oil, reaction temperature and catalyst quantity. The paper concludes that the ANN can be successfully used to optimize the biodiesel yield.
Artificial neural network ANN is an appropriate tool for predestining the different relationships... more Artificial neural network ANN is an appropriate tool for predestining the different relationships across many scientific researches. Air emissions prediction is an effective method of securing public health by revealing the imminent danger of air pollutants. So far, the existing methods of air emissions concentration prediction became useless on long-term dependencies, and most neglect spatial correlations. In this study, an artificial neural network model, which also takes into account the spatial-temporal variable, is proposed for prediction of air emission. The ANN was used in order to take into account the historical data, auxiliary data such as environmental quality and weather conditions. Evaluation of the results revealed that the developed ANN model appears to be an appropriate tool in predicting environmental air emissions. The data were collected from 12 air quality-monitoring stations from a random county in Romania. The proposed model performed well and presented a relat...
We herein report on the synthesis by a facile sol-gel method without templates for preparing ruti... more We herein report on the synthesis by a facile sol-gel method without templates for preparing rutile RuxTi1-xO2 (x = 0.16; 0.07; 0.01) nanobelts with exposed (001) facets. The rutile nanobelts with exposure (001) facets, favor the separation photogenerated electron-hole pairs and inhibit the recombination of the electron-hole pairs resulting in the increase of the number of main superoxide and hydroxyl radicals. The photocatalytic properties of the rutile RuxTi1-xO2 nanobelts were evaluated by discoloring of MB (methylene blue) dye under sunlight irradiation at an intensity of 40000 lx. It was also done a thorough interface analysis to determine the band energy.
A series of solid acid catalyst of the Keggin-type 12-phosphotungstic acid, H3PW12O40, supported ... more A series of solid acid catalyst of the Keggin-type 12-phosphotungstic acid, H3PW12O40, supported on ordered mesoporous silica MCM-41 were prepared by a simple and effective impregnation method. MCM-41 supports were synthesized in a relatively short time via a recently reported ultrasonic irradiation method. The synthesis sonication time has been systematically varied in order to investigate its influence on the structural order of the resulting materials. The prepared catalysts were characterized by nitrogen adsorption, X-ray diffraction, Raman spectroscopy and thermogravimetric analysis. The resulting materials exhibited hexagonally ordered meso structure, with high surface area of the order of several hundreds of m2g-1,relatively large pore volumes, with the pore diameter in the range of 2.19 to 2.41 nm and a corresponding pore wall thickness of over 1.67nm. The results have demonstrated that high quality MCM-41 materials can be synthesized via the ultrasonic irradiation in few te...
A Co/CeO2 catalyst for ethanol steam reforming process was prepared and characterized using diffe... more A Co/CeO2 catalyst for ethanol steam reforming process was prepared and characterized using different characterization techniques including X-ray diffraction, UV-Vis diffuse reflectance, FTIR spectroscopy, scanning electron microscopy (SEM), N2 adsorption/desorption isotherms (BET) and thermal analysis method (TGA). The catalytic test in ethanol steam reforming process showed a high H2 yield and almost complete ethanol conversion.
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