Tamer Sharara | Egyptian Academy (original) (raw)

Papers by Tamer Sharara

The catalytic conversion of the main pollutants in the exhausted gas carbon monoxide and nitric o... more The catalytic conversion of the main pollutants in the exhausted gas carbon monoxide and nitric oxide to environmental friendly gas was carried out using iron and manganese ore samples. The ores have been characterized through X-ray and differential scanning calorimetry analyses. Tests for the carbon monoxide oxidation were performed in a catalytic flow system, operated under atmospheric pressure, at constant response time sixty minutes, inlet carbon monoxide 270ppm and with stepwise increase of reaction temperature from 100 to 500oC. The effect of carbon monoxide inlet concentration was also tested for higher concentrations, i.e. up to 23300ppm. Finally, to distinct the difference between the endurance ability of the most active materials, the effect of carbon monoxide inlet concentration factor, was tested. The toleration capabilities of the samples were compared at experimentally vigorous conditions; i.e. the inlet carbon monoxide concentration reached 90,000ppm. The reduction of...

Egyptian Journal of Chemistry, 2019

T HE manganese based MOF (Mn(BDC)(H 2 O) 2); was successfully synthesized via a microwave method.... more T HE manganese based MOF (Mn(BDC)(H 2 O) 2); was successfully synthesized via a microwave method. The features of the Mn-MOF was evaluated by XRD, TGA, N 2 adsorption-desorption at-196ºC, FTIR and SEM. The elimination of heavy metal ions from aqueous solution via Mn-MOF was described by batch adsorption tests including kinetic and thermodynamic models. Mn-MOF exhibited a very high adsorption efficiency towards Cd(II), Pb(II) and Hg(II) from aqueous solution (81.89%, 71.19% and 65.19% respectively). Adsorption kinetics data evidenced that heavy metal ions adsorption isotherms appropriated the Langmuir model and conform the pseudo-second-order kinetic equation. Successfully, the Mn-MOF was reused illustrative in the first run, the adsorbed amounts for (Cd(II), pb(II) and Hg(II)) were (80.2%, 69.6% and 64%) after fifth run became (68%, 54.74% and 50.98% respectively) which is elucidating its potential for heavy metal ions decontamination application.

Journal of Chemical Sciences, 2014

Multioxide catalysts of zinc, copper and titanium with different ratios obtained from layered dou... more Multioxide catalysts of zinc, copper and titanium with different ratios obtained from layered double hydroxide (LDH) precursors were used in the oxidation of carbon monoxide. The catalysts were characterized by energy-dispersive X-ray spectrometry, X-ray diffraction, thermal analyses (TG, DTG and DTA) and scanning electron microscopy. X-ray diffraction showed different phases of double hydroxide structures. On increasing the percentage of zinc, hydrotalcite structure became the main phase in these samples. SEM images confirmed the presence of layered double hydroxide as plate-like structure. Experimental results indicated a sharp increase in the catalytic activities of the calcined samples towards the oxidation of carbon monoxide at temperatures in the range of 225-275 • C. High conversion of carbon monoxide (90 ∼ 95%) was achieved at reaction temperature of 275 • C by samples having ZnTiO 3 as a main phase. These results suggested that hydrotalcite structure of Zn-Ti has a positive catalytic effect towards carbon monoxide oxidation.

Microporous and Mesoporous Materials, 2017

In this study, Cu 3 (BTC) 2 and Ni 1.5-Cu 1.5 (BTC) 2 were synthesized in the presence of microwa... more In this study, Cu 3 (BTC) 2 and Ni 1.5-Cu 1.5 (BTC) 2 were synthesized in the presence of microwave irradiation. The morphology and the structure of the prepared MOFs were characterized by XRD, TEM, TGA, FTIR, Raman, and nitrogen adsorption/desorption methods. The adsorption activities of the samples towards the phenols from aqueous solutions were achieved including kinetic and equilibrium approaches with different nonlinear models for modeling. The experimental data clarified that the adsorption of phenols on Cu 3 (BTC) 2 and Ni 1.5 Cu 1.5 (BTC) 2 had been processed via a pore-filling mechanism. Thermodynamic parameters were also determined. Furthermore, a three levels-four factor half-factorial design was successfully employed for experimental design and analysis of the results through response surface methodology (RSM). The significance of the independent variables was tested and optimized by the analysis of variance (ANOVA) and t-test statistics. The optimum pH, adsorbent dose, and temperature were found to be 5.0, 1 g/l, and 30 o C, respectively, for both samples. Under these conditions, the predicted removal efficiency of 50 mg/L phenols was found to be 71.32% (35.65 mg/g) and 78.95% (39.47 mg/g), respectively. Keywords: Metal-organic frameworks; Cu 3 (BTC) 2 ; Ni 1.5 Cu 1.5 (BTC) 2 ; phenol; adsorption. 2. Experimental: 2.1 Synthesis and characterization of Cu 3 (BTC) 2 .3H 2 O and Ni 1.5 Cu 1.5 (BTC) 2 .3H 2 O Highlights > Cu 3 (BTC) 2 and Ni 1.5-Cu 1.5 (BTC) 2 were synthesized and characterized. > The affinities of MOFs towards the phenols in the aqueous medium were evaluated. > NiCu MOF removed ~79% of 50 mg/L phenols at the optimum experimental conditions.

Journal of Natural Gas Science and Engineering, 2016

Natural gas (NG) is a naturally gaseous hydrocarbon mixture that is formed under the earth`s surf... more Natural gas (NG) is a naturally gaseous hydrocarbon mixture that is formed under the earth`s surface. NG is considered to be the cleanest fossil fuel and is a safe source of energy when transported, stored and used. The primary constituent of NG is methane, it may also contain (C 2 + hydrocarbons, N 2 , CO 2 , He, H 2 S, and noble gases) according to its origin. Different gas processing technologies can be employed to remove constituents other than methane. Due to importance of NG as a fuel and the increasing global demand of it, this article reviews the fundamentals of NG origin, composition, and processing.

Chemical Engineering Journal, 2017

Cellulose-magnetite nanocomposites were fabricated via the adsorption of magnetite onto the surfa... more Cellulose-magnetite nanocomposites were fabricated via the adsorption of magnetite onto the surfaces of functionalized nanocellulose, using different organic and inorganic acids. The properties of functionalized nanocellulose derivatives and cellulose-magnetite nanocomposites were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray, Fourier transform infrared spectroscopy (FTIR), magnetic properties measurement (VSM), and thermal analysis. The catalytic activity of the functionalized nanocellulose and cellulose-magnetite nanocomposites was evaluated towards the esterification of oleic acid with methanol for the production of methyl oleate (biodiesel). The sulfonated cellulose-magnetite nanocomposite (MSNC) showed a high catalytic activity toward the esterification reaction (96 %) due to the high dispersion of the Lewis acid sites resulted from the impregnation of magnetite (0.98 wt%) in addition to the already presented Brönsted acid sites in the surface of the nanocellulose.

Energy & Fuels, 2016

Unprocessed petroleum hydrocarbons often contain high concentrations of mercury (Hg), which can s... more Unprocessed petroleum hydrocarbons often contain high concentrations of mercury (Hg), which can severely damage the metal components of a processing plant and pose a health risk to the workers and the natural environment. Although Hg removal units can significantly reduce the Hg concentration in the export products, they are often installed in the final stage of the processing plant, thus failing to protect the production facilities. In this study, Hg distribution within a natural gas processing plant was studied to identify the most effective place for a Hg removal unit. Additionally, the impact of sampling container materials and their acidification was evaluated, and Hg species in the condensate were quantified. Total Hg concentration was significantly higher in all samples stored in glass in comparison to that with plastic containers. However, the acidification effect of the containers was more pronounced for Hg in nonpolar solutions. Interestingly, the assessment of Hg distribution within the gas pla...

Journal of Sol-Gel Science and Technology, 2016

Iron-tungsten oxide nanospinel have been prepared by two methods: microwave combustion method and... more Iron-tungsten oxide nanospinel have been prepared by two methods: microwave combustion method and Pechini method. The W-Fe bimetallic ferberite was successfully synthesized by microwave-assisted techniques. The resultant magnetic nanocomposites were characterized by thermal analysis, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, energy-dispersive X-ray, transmission electron microscopy, nitrogen adsorption, and magnetic properties measurement system. The prepared ferberite nanoparticles (50-65 nm) using microwave combustion method were pure monoclinic ferberite. The ferberite nanoparticles showed ferrimagnetic hysteresis loop with values of saturation magnetization and coercivity of 4.829 A.m 2 /Kg and 0.0312 T, successively. Keywords Magnetic ferberite • Microwave-assisted synthesis • Wolframite structure • Pechini synthesis • FeWO 4

Chemical and Process Engineering Research, 2014

La 0.6 Sr 0.4 NiO 3 perovskite-type oxides were prepared by reverse microemulsion method aided by... more La 0.6 Sr 0.4 NiO 3 perovskite-type oxides were prepared by reverse microemulsion method aided by ultrasonic homogenizer. The mixed oxide precursors and the corresponding derived fresh catalysts were characterized by thermogravimetry and differential thermal analysis (TG/DTA), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area and high resolution transmission electron microscope (HRTEM). XRD results reveal that pure phase of perovskite-type crystalline structure was obtained for all samples and the electronic unbalance caused by the partial substitution for La 3+ by Sr 2+ is compensated by oxidation of a fraction of Ni 3+ to Ni 4+ and/or generation of oxygen vacancies in the perovskite lattice. There exist two kinds of oxygen species on the oxides: surface adsorption oxygen and bulk lattice oxygen. The surface oxygen contributed to oxidize methane completely to CO 2 and H 2 O because of its higher reactivity, while the other one prone to oxidative coupling of methane into C 2 H 6 and C 2 H 2 (C 2+). In this study a mathematical model for the oxidative coupling of methane (OCM) over La 0.6 Sr 0.4 NiO 3 pervoskite is developed. From this simulation it can predict that the activity at temperature ≥ 925 ºC and methane partial pressure =0.3 and oxygen partial pressure =0.1 will be reach ~10% and selectivity ~50%.

Chemistry and Materials Research, 2014

Novel nanosized molybdenum-tungsten bimetallic oxides were prepared by modified Pechini method ba... more Novel nanosized molybdenum-tungsten bimetallic oxides were prepared by modified Pechini method based on the low temperature polymerization-complexation steps. The physical properties of the prepared nanoparticles were characterized by: X-ray diffraction (XRD), Fourier transformer inferred spectroscopy (FT-IR), differential thermal analyses (DCS), and high resolution transmission electron microscopy (HRTEM). The influence of metal molar ratios (Mo/W) on the morphology and the crystallization the samples was also investigated. The adsorptive power of prepared samples was evaluated through the removal of dimethyl disulfide sulfur compound (in cyclohexane as fuel). The results indicate that all the prepared MoW oxide materials are nanoparticles with diameter ranging between 1 and 70 nm. And the smallest nanosize particles enhanced the adsorptive power of the prepared nanostructured MoW bimetallic oxide.

Petroleum Science and Technology, 2005

Abstract The effect of thermal pretreatment on manganese material properties was investigated via... more Abstract The effect of thermal pretreatment on manganese material properties was investigated via XRF, DSC, XRD, MIP, and surface acidity measurements. The catalytic activity toward dehydration of different alcohols ethanol (in comparison with synthetic manganese catalyst), 1-propanol and 1-butanol was also carried out in a catalytic flow type system in the presence of hydrogen stream under atmospheric pressure with reaction temperatures ranging from 200–550°C and at different space velocities between 0.46–15.40 h−1. The results showed an agreement between manganese calcined material and the prepared catalyst in the optimum reaction temperature required for the dehydration of ethanol to ethylene, as well as the selectivity values. Data showed decrease in total dehydration conversion percentage in the order ethanol > 1-propanol > 1-butanol.

Journal of the Taiwan Institute of Chemical Engineers, 2013

Abstract Zinc–aluminum layered double hydroxides (Zn–Al LDHs) with different Zn/Al ratios (Zn/Al ... more Abstract Zinc–aluminum layered double hydroxides (Zn–Al LDHs) with different Zn/Al ratios (Zn/Al = 6, 3 and 2) were prepared using a homogenous precipitation method by urea hydrolysis. The preparation was performed at various temperatures (70–100 °C). The element chemical analysis, X-ray powder diffraction and Fourier transform infrared spectra show that urea species and cyanate anions are the main anions intercalated at low temperature and low Zn/Al ratios. This was confirmed by pH curves recorded during the reaction, thermal analyses, temperature programmed desorption. The presence of intercalated urea and cyanate species creates UV absorption activities for the ZA15-80 and ZA35-80 samples and enhance the selectivity of ZA15-80 toward the adsorption of carbon dioxide from natural gas.

Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2014

ABSTRACT

Petroleum Science and Technology, 2011

ABSTRACT Micro-alloyed nickel aluminide Ni3Al and boron-doped Ni3Al, containing 0.15 wt% B, were ... more ABSTRACT Micro-alloyed nickel aluminide Ni3Al and boron-doped Ni3Al, containing 0.15 wt% B, were processed via powder metallurgy. The effect of the boron on the crystalline structure, porosity, surface area, and toluene catalytic hydrogenation was studied.The results indicate that the doping of boron decreases the percentage total porosity of micro-alloyed nickel aluminide. Consequently, slight grain growth in the case of B-doped alloy occurred.Such changes in the alloy structure had a negative influence on the catalytic activity of the nickel aluminide as a catalyst where the selectivity of the alloy toward the hydrogenation of toluene decreased from ~95 to ~64%.

Petroleum Science and Technology, 2005

The effect of mixing both local Egyptian hematitic ore and activated aluminosilicate material (be... more The effect of mixing both local Egyptian hematitic ore and activated aluminosilicate material (bentonite clay) on the dehydrogenation activity of the former was studied.Three mixtures were prepared in which bentonite percentages were 10, 20, and 40 wt%. Cyclohexane used as a model reactant for the catalytic dehydrogenation reaction carried out in catalytic flow system within reaction temperature ranged from 150

Journal of Sol-Gel Science and Technology, 2012

Nanoparticles of ferrites (Fe 3 O 4 , NiFe 2 O 4 , CuFe 2 O 4 , and MnFe 2 O 4) were prepared by ... more Nanoparticles of ferrites (Fe 3 O 4 , NiFe 2 O 4 , CuFe 2 O 4 , and MnFe 2 O 4) were prepared by a reverse (water/oil) microemulsion method. The microemulsion system consisted of cetyltrimethylammonium bromide, 1-butanol, cyclohexane, and a metal salt solution. The procedure was carried out using aqueous ammonia as the coprecipitating agent. Nanosized particles were characterized by thermal analysis, X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, and pyridine adsorption. The NiFe 2 O 4 sample exhibited narrow mesoporous pore size distribution and high surface area &233 m 2 /g. It achieved good adsorption activity towards the dibenzothiophene (DBT) compound (166.3 lmol/g of DBT adsorbent). The structural properties obtained were very interesting for potential applications in the desulfurization process in petroleum refining.

Journal of Colloid and Interface Science, 2005

The aim of this work is to study catalytic ethanol dehydration using different prepared catalysts... more The aim of this work is to study catalytic ethanol dehydration using different prepared catalysts, which include Fe 2 O 3 , Mn 2 O 3 , and calcined physical mixtures of both ferric and manganese oxides with alumina and/or silica gel. The physicochemical properties of these catalysts were investigated via X-ray powder diffraction (XRD), acidity measurement, and nitrogen adsorption-desorption at −196 • C. The catalytic activities of such catalysts were tested through conversion of ethanol at 200-500 • C using a catalytic flow system operated under atmospheric pressure. The results obtained indicated that the dehydration reaction on the catalyst relies on surface acidity, whereas the ethylene production selectivity depends on the catalyst chemical constituents.

Fuel Processing Technology, 2013

High surface area γ-alumina adsorbents (302-376 m 2 /g) were prepared by using different cationic... more High surface area γ-alumina adsorbents (302-376 m 2 /g) were prepared by using different cationic surfactants in the presence of microwave irradiation. The adsorbents were characterized by DSC/TG, X-ray diffraction, nitrogen physisorption, and HRTEM techniques. To evaluate the influence of the surface features of alumina on its activity, its adsorption capacity for aromatic and sulfur compounds from petroleum waxes, Suez crude petrolatum was used for this investigation. Results clearly indicated that nano-alumina materials showed high efficiency for removing aromatics and sulfur compounds from Suez crude petrolatum. In the same run, it completely removed di-aromatics especially for AN5 sample. This leads to an improvement for the physical properties of Suez crude petrolatum which has been widely used in many applications such as household chemicals as candles and polishes, pharmaceutical, cosmetic as lipsticks, building construction, paper, match, rubber and other industrial purposes.

Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2012

In this work, the catalytic activity of copper/silica nanocatalysts (prepared by incipient wetnes... more In this work, the catalytic activity of copper/silica nanocatalysts (prepared by incipient wetness impregnation of the metal salt on nanosilica, thermally extracted from rice husk) on the oxidation of carbon monoxide is investigated. The effect of metal loading on the physico-chemical features of the prepared catalysts has been investigated by X-ray diffraction, differential thermal analysis, transmission electron microscopy, nitrogen adsorption-desorption

Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2012

Abstract In this work, nanosized manganese catalysts were prepared by incipient wetness impregnat... more Abstract In this work, nanosized manganese catalysts were prepared by incipient wetness impregnation of manganese salt on nanosilica. The nanosilica was thermally extracted from rice husk. The effect of metal oxide loading on the physico-chemical features and the catalytic activities of the catalysts towards the oxidation of carbon monoxide were investigated. Nanocatalyst loaded with 20.1 wt% manganese oxide (Mn20) was distinguished by the high surface area accompanied by the creation of new mesopores with respect to parent nanosilica. The X-ray diffraction and H2-temperature programmed reduction analyses indicated that the Mn5O8 phase was the predominant phase in Mn20 catalyst. The presence of the Mn5O8 phase, in addition to the high surface area of Mn20 catalyst, resulted in decreasing the conversion temperature of CO oxidation (T50), where the CO oxidation may follow the Mars-van-Krevelen route, i.e., redox mechanism.

The catalytic conversion of the main pollutants in the exhausted gas carbon monoxide and nitric o... more The catalytic conversion of the main pollutants in the exhausted gas carbon monoxide and nitric oxide to environmental friendly gas was carried out using iron and manganese ore samples. The ores have been characterized through X-ray and differential scanning calorimetry analyses. Tests for the carbon monoxide oxidation were performed in a catalytic flow system, operated under atmospheric pressure, at constant response time sixty minutes, inlet carbon monoxide 270ppm and with stepwise increase of reaction temperature from 100 to 500oC. The effect of carbon monoxide inlet concentration was also tested for higher concentrations, i.e. up to 23300ppm. Finally, to distinct the difference between the endurance ability of the most active materials, the effect of carbon monoxide inlet concentration factor, was tested. The toleration capabilities of the samples were compared at experimentally vigorous conditions; i.e. the inlet carbon monoxide concentration reached 90,000ppm. The reduction of...

Egyptian Journal of Chemistry, 2019

T HE manganese based MOF (Mn(BDC)(H 2 O) 2); was successfully synthesized via a microwave method.... more T HE manganese based MOF (Mn(BDC)(H 2 O) 2); was successfully synthesized via a microwave method. The features of the Mn-MOF was evaluated by XRD, TGA, N 2 adsorption-desorption at-196ºC, FTIR and SEM. The elimination of heavy metal ions from aqueous solution via Mn-MOF was described by batch adsorption tests including kinetic and thermodynamic models. Mn-MOF exhibited a very high adsorption efficiency towards Cd(II), Pb(II) and Hg(II) from aqueous solution (81.89%, 71.19% and 65.19% respectively). Adsorption kinetics data evidenced that heavy metal ions adsorption isotherms appropriated the Langmuir model and conform the pseudo-second-order kinetic equation. Successfully, the Mn-MOF was reused illustrative in the first run, the adsorbed amounts for (Cd(II), pb(II) and Hg(II)) were (80.2%, 69.6% and 64%) after fifth run became (68%, 54.74% and 50.98% respectively) which is elucidating its potential for heavy metal ions decontamination application.

Journal of Chemical Sciences, 2014

Multioxide catalysts of zinc, copper and titanium with different ratios obtained from layered dou... more Multioxide catalysts of zinc, copper and titanium with different ratios obtained from layered double hydroxide (LDH) precursors were used in the oxidation of carbon monoxide. The catalysts were characterized by energy-dispersive X-ray spectrometry, X-ray diffraction, thermal analyses (TG, DTG and DTA) and scanning electron microscopy. X-ray diffraction showed different phases of double hydroxide structures. On increasing the percentage of zinc, hydrotalcite structure became the main phase in these samples. SEM images confirmed the presence of layered double hydroxide as plate-like structure. Experimental results indicated a sharp increase in the catalytic activities of the calcined samples towards the oxidation of carbon monoxide at temperatures in the range of 225-275 • C. High conversion of carbon monoxide (90 ∼ 95%) was achieved at reaction temperature of 275 • C by samples having ZnTiO 3 as a main phase. These results suggested that hydrotalcite structure of Zn-Ti has a positive catalytic effect towards carbon monoxide oxidation.

Microporous and Mesoporous Materials, 2017

In this study, Cu 3 (BTC) 2 and Ni 1.5-Cu 1.5 (BTC) 2 were synthesized in the presence of microwa... more In this study, Cu 3 (BTC) 2 and Ni 1.5-Cu 1.5 (BTC) 2 were synthesized in the presence of microwave irradiation. The morphology and the structure of the prepared MOFs were characterized by XRD, TEM, TGA, FTIR, Raman, and nitrogen adsorption/desorption methods. The adsorption activities of the samples towards the phenols from aqueous solutions were achieved including kinetic and equilibrium approaches with different nonlinear models for modeling. The experimental data clarified that the adsorption of phenols on Cu 3 (BTC) 2 and Ni 1.5 Cu 1.5 (BTC) 2 had been processed via a pore-filling mechanism. Thermodynamic parameters were also determined. Furthermore, a three levels-four factor half-factorial design was successfully employed for experimental design and analysis of the results through response surface methodology (RSM). The significance of the independent variables was tested and optimized by the analysis of variance (ANOVA) and t-test statistics. The optimum pH, adsorbent dose, and temperature were found to be 5.0, 1 g/l, and 30 o C, respectively, for both samples. Under these conditions, the predicted removal efficiency of 50 mg/L phenols was found to be 71.32% (35.65 mg/g) and 78.95% (39.47 mg/g), respectively. Keywords: Metal-organic frameworks; Cu 3 (BTC) 2 ; Ni 1.5 Cu 1.5 (BTC) 2 ; phenol; adsorption. 2. Experimental: 2.1 Synthesis and characterization of Cu 3 (BTC) 2 .3H 2 O and Ni 1.5 Cu 1.5 (BTC) 2 .3H 2 O Highlights > Cu 3 (BTC) 2 and Ni 1.5-Cu 1.5 (BTC) 2 were synthesized and characterized. > The affinities of MOFs towards the phenols in the aqueous medium were evaluated. > NiCu MOF removed ~79% of 50 mg/L phenols at the optimum experimental conditions.

Journal of Natural Gas Science and Engineering, 2016

Natural gas (NG) is a naturally gaseous hydrocarbon mixture that is formed under the earth`s surf... more Natural gas (NG) is a naturally gaseous hydrocarbon mixture that is formed under the earth`s surface. NG is considered to be the cleanest fossil fuel and is a safe source of energy when transported, stored and used. The primary constituent of NG is methane, it may also contain (C 2 + hydrocarbons, N 2 , CO 2 , He, H 2 S, and noble gases) according to its origin. Different gas processing technologies can be employed to remove constituents other than methane. Due to importance of NG as a fuel and the increasing global demand of it, this article reviews the fundamentals of NG origin, composition, and processing.

Chemical Engineering Journal, 2017

Cellulose-magnetite nanocomposites were fabricated via the adsorption of magnetite onto the surfa... more Cellulose-magnetite nanocomposites were fabricated via the adsorption of magnetite onto the surfaces of functionalized nanocellulose, using different organic and inorganic acids. The properties of functionalized nanocellulose derivatives and cellulose-magnetite nanocomposites were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray, Fourier transform infrared spectroscopy (FTIR), magnetic properties measurement (VSM), and thermal analysis. The catalytic activity of the functionalized nanocellulose and cellulose-magnetite nanocomposites was evaluated towards the esterification of oleic acid with methanol for the production of methyl oleate (biodiesel). The sulfonated cellulose-magnetite nanocomposite (MSNC) showed a high catalytic activity toward the esterification reaction (96 %) due to the high dispersion of the Lewis acid sites resulted from the impregnation of magnetite (0.98 wt%) in addition to the already presented Brönsted acid sites in the surface of the nanocellulose.

Energy & Fuels, 2016

Unprocessed petroleum hydrocarbons often contain high concentrations of mercury (Hg), which can s... more Unprocessed petroleum hydrocarbons often contain high concentrations of mercury (Hg), which can severely damage the metal components of a processing plant and pose a health risk to the workers and the natural environment. Although Hg removal units can significantly reduce the Hg concentration in the export products, they are often installed in the final stage of the processing plant, thus failing to protect the production facilities. In this study, Hg distribution within a natural gas processing plant was studied to identify the most effective place for a Hg removal unit. Additionally, the impact of sampling container materials and their acidification was evaluated, and Hg species in the condensate were quantified. Total Hg concentration was significantly higher in all samples stored in glass in comparison to that with plastic containers. However, the acidification effect of the containers was more pronounced for Hg in nonpolar solutions. Interestingly, the assessment of Hg distribution within the gas pla...

Journal of Sol-Gel Science and Technology, 2016

Iron-tungsten oxide nanospinel have been prepared by two methods: microwave combustion method and... more Iron-tungsten oxide nanospinel have been prepared by two methods: microwave combustion method and Pechini method. The W-Fe bimetallic ferberite was successfully synthesized by microwave-assisted techniques. The resultant magnetic nanocomposites were characterized by thermal analysis, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, energy-dispersive X-ray, transmission electron microscopy, nitrogen adsorption, and magnetic properties measurement system. The prepared ferberite nanoparticles (50-65 nm) using microwave combustion method were pure monoclinic ferberite. The ferberite nanoparticles showed ferrimagnetic hysteresis loop with values of saturation magnetization and coercivity of 4.829 A.m 2 /Kg and 0.0312 T, successively. Keywords Magnetic ferberite • Microwave-assisted synthesis • Wolframite structure • Pechini synthesis • FeWO 4

Chemical and Process Engineering Research, 2014

La 0.6 Sr 0.4 NiO 3 perovskite-type oxides were prepared by reverse microemulsion method aided by... more La 0.6 Sr 0.4 NiO 3 perovskite-type oxides were prepared by reverse microemulsion method aided by ultrasonic homogenizer. The mixed oxide precursors and the corresponding derived fresh catalysts were characterized by thermogravimetry and differential thermal analysis (TG/DTA), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area and high resolution transmission electron microscope (HRTEM). XRD results reveal that pure phase of perovskite-type crystalline structure was obtained for all samples and the electronic unbalance caused by the partial substitution for La 3+ by Sr 2+ is compensated by oxidation of a fraction of Ni 3+ to Ni 4+ and/or generation of oxygen vacancies in the perovskite lattice. There exist two kinds of oxygen species on the oxides: surface adsorption oxygen and bulk lattice oxygen. The surface oxygen contributed to oxidize methane completely to CO 2 and H 2 O because of its higher reactivity, while the other one prone to oxidative coupling of methane into C 2 H 6 and C 2 H 2 (C 2+). In this study a mathematical model for the oxidative coupling of methane (OCM) over La 0.6 Sr 0.4 NiO 3 pervoskite is developed. From this simulation it can predict that the activity at temperature ≥ 925 ºC and methane partial pressure =0.3 and oxygen partial pressure =0.1 will be reach ~10% and selectivity ~50%.

Chemistry and Materials Research, 2014

Novel nanosized molybdenum-tungsten bimetallic oxides were prepared by modified Pechini method ba... more Novel nanosized molybdenum-tungsten bimetallic oxides were prepared by modified Pechini method based on the low temperature polymerization-complexation steps. The physical properties of the prepared nanoparticles were characterized by: X-ray diffraction (XRD), Fourier transformer inferred spectroscopy (FT-IR), differential thermal analyses (DCS), and high resolution transmission electron microscopy (HRTEM). The influence of metal molar ratios (Mo/W) on the morphology and the crystallization the samples was also investigated. The adsorptive power of prepared samples was evaluated through the removal of dimethyl disulfide sulfur compound (in cyclohexane as fuel). The results indicate that all the prepared MoW oxide materials are nanoparticles with diameter ranging between 1 and 70 nm. And the smallest nanosize particles enhanced the adsorptive power of the prepared nanostructured MoW bimetallic oxide.

Petroleum Science and Technology, 2005

Abstract The effect of thermal pretreatment on manganese material properties was investigated via... more Abstract The effect of thermal pretreatment on manganese material properties was investigated via XRF, DSC, XRD, MIP, and surface acidity measurements. The catalytic activity toward dehydration of different alcohols ethanol (in comparison with synthetic manganese catalyst), 1-propanol and 1-butanol was also carried out in a catalytic flow type system in the presence of hydrogen stream under atmospheric pressure with reaction temperatures ranging from 200–550°C and at different space velocities between 0.46–15.40 h−1. The results showed an agreement between manganese calcined material and the prepared catalyst in the optimum reaction temperature required for the dehydration of ethanol to ethylene, as well as the selectivity values. Data showed decrease in total dehydration conversion percentage in the order ethanol > 1-propanol > 1-butanol.

Journal of the Taiwan Institute of Chemical Engineers, 2013

Abstract Zinc–aluminum layered double hydroxides (Zn–Al LDHs) with different Zn/Al ratios (Zn/Al ... more Abstract Zinc–aluminum layered double hydroxides (Zn–Al LDHs) with different Zn/Al ratios (Zn/Al = 6, 3 and 2) were prepared using a homogenous precipitation method by urea hydrolysis. The preparation was performed at various temperatures (70–100 °C). The element chemical analysis, X-ray powder diffraction and Fourier transform infrared spectra show that urea species and cyanate anions are the main anions intercalated at low temperature and low Zn/Al ratios. This was confirmed by pH curves recorded during the reaction, thermal analyses, temperature programmed desorption. The presence of intercalated urea and cyanate species creates UV absorption activities for the ZA15-80 and ZA35-80 samples and enhance the selectivity of ZA15-80 toward the adsorption of carbon dioxide from natural gas.

Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2014

ABSTRACT

Petroleum Science and Technology, 2011

ABSTRACT Micro-alloyed nickel aluminide Ni3Al and boron-doped Ni3Al, containing 0.15 wt% B, were ... more ABSTRACT Micro-alloyed nickel aluminide Ni3Al and boron-doped Ni3Al, containing 0.15 wt% B, were processed via powder metallurgy. The effect of the boron on the crystalline structure, porosity, surface area, and toluene catalytic hydrogenation was studied.The results indicate that the doping of boron decreases the percentage total porosity of micro-alloyed nickel aluminide. Consequently, slight grain growth in the case of B-doped alloy occurred.Such changes in the alloy structure had a negative influence on the catalytic activity of the nickel aluminide as a catalyst where the selectivity of the alloy toward the hydrogenation of toluene decreased from ~95 to ~64%.

Petroleum Science and Technology, 2005

The effect of mixing both local Egyptian hematitic ore and activated aluminosilicate material (be... more The effect of mixing both local Egyptian hematitic ore and activated aluminosilicate material (bentonite clay) on the dehydrogenation activity of the former was studied.Three mixtures were prepared in which bentonite percentages were 10, 20, and 40 wt%. Cyclohexane used as a model reactant for the catalytic dehydrogenation reaction carried out in catalytic flow system within reaction temperature ranged from 150

Journal of Sol-Gel Science and Technology, 2012

Nanoparticles of ferrites (Fe 3 O 4 , NiFe 2 O 4 , CuFe 2 O 4 , and MnFe 2 O 4) were prepared by ... more Nanoparticles of ferrites (Fe 3 O 4 , NiFe 2 O 4 , CuFe 2 O 4 , and MnFe 2 O 4) were prepared by a reverse (water/oil) microemulsion method. The microemulsion system consisted of cetyltrimethylammonium bromide, 1-butanol, cyclohexane, and a metal salt solution. The procedure was carried out using aqueous ammonia as the coprecipitating agent. Nanosized particles were characterized by thermal analysis, X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, and pyridine adsorption. The NiFe 2 O 4 sample exhibited narrow mesoporous pore size distribution and high surface area &233 m 2 /g. It achieved good adsorption activity towards the dibenzothiophene (DBT) compound (166.3 lmol/g of DBT adsorbent). The structural properties obtained were very interesting for potential applications in the desulfurization process in petroleum refining.

Journal of Colloid and Interface Science, 2005

The aim of this work is to study catalytic ethanol dehydration using different prepared catalysts... more The aim of this work is to study catalytic ethanol dehydration using different prepared catalysts, which include Fe 2 O 3 , Mn 2 O 3 , and calcined physical mixtures of both ferric and manganese oxides with alumina and/or silica gel. The physicochemical properties of these catalysts were investigated via X-ray powder diffraction (XRD), acidity measurement, and nitrogen adsorption-desorption at −196 • C. The catalytic activities of such catalysts were tested through conversion of ethanol at 200-500 • C using a catalytic flow system operated under atmospheric pressure. The results obtained indicated that the dehydration reaction on the catalyst relies on surface acidity, whereas the ethylene production selectivity depends on the catalyst chemical constituents.

Fuel Processing Technology, 2013

High surface area γ-alumina adsorbents (302-376 m 2 /g) were prepared by using different cationic... more High surface area γ-alumina adsorbents (302-376 m 2 /g) were prepared by using different cationic surfactants in the presence of microwave irradiation. The adsorbents were characterized by DSC/TG, X-ray diffraction, nitrogen physisorption, and HRTEM techniques. To evaluate the influence of the surface features of alumina on its activity, its adsorption capacity for aromatic and sulfur compounds from petroleum waxes, Suez crude petrolatum was used for this investigation. Results clearly indicated that nano-alumina materials showed high efficiency for removing aromatics and sulfur compounds from Suez crude petrolatum. In the same run, it completely removed di-aromatics especially for AN5 sample. This leads to an improvement for the physical properties of Suez crude petrolatum which has been widely used in many applications such as household chemicals as candles and polishes, pharmaceutical, cosmetic as lipsticks, building construction, paper, match, rubber and other industrial purposes.

Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2012

In this work, the catalytic activity of copper/silica nanocatalysts (prepared by incipient wetnes... more In this work, the catalytic activity of copper/silica nanocatalysts (prepared by incipient wetness impregnation of the metal salt on nanosilica, thermally extracted from rice husk) on the oxidation of carbon monoxide is investigated. The effect of metal loading on the physico-chemical features of the prepared catalysts has been investigated by X-ray diffraction, differential thermal analysis, transmission electron microscopy, nitrogen adsorption-desorption

Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2012

Abstract In this work, nanosized manganese catalysts were prepared by incipient wetness impregnat... more Abstract In this work, nanosized manganese catalysts were prepared by incipient wetness impregnation of manganese salt on nanosilica. The nanosilica was thermally extracted from rice husk. The effect of metal oxide loading on the physico-chemical features and the catalytic activities of the catalysts towards the oxidation of carbon monoxide were investigated. Nanocatalyst loaded with 20.1 wt% manganese oxide (Mn20) was distinguished by the high surface area accompanied by the creation of new mesopores with respect to parent nanosilica. The X-ray diffraction and H2-temperature programmed reduction analyses indicated that the Mn5O8 phase was the predominant phase in Mn20 catalyst. The presence of the Mn5O8 phase, in addition to the high surface area of Mn20 catalyst, resulted in decreasing the conversion temperature of CO oxidation (T50), where the CO oxidation may follow the Mars-van-Krevelen route, i.e., redox mechanism.