The efficacy of using blank alginate beads and immobilized dead algal cells for the removal of zi... more The efficacy of using blank alginate beads and immobilized dead algal cells for the removal of zinc ions from aqueous solutions was investigated. It was found that the sorption capacities were significantly affected by solution pH; with higher pH favoring higher zinc ion uptake. Dynamics and isotherm experiments were carried out at the optimal pH 5.0. Zinc uptake on either sorbent was found to be rapid where approximately 90% of the maximum zinc uptake occurred within the first 30 min in both cases of blank alginate and immobilized algal cells. The equilibrium data for the biosorption of zinc ions onto both sorbents were fitted to the Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm equations. The presence of copper and nickel in aqueous solutions was found to suppress the sorption process. The results of the dynamics studies revealed that the biosorption of zinc on immobilized dead algal cells followed pseudo-second order kinetics with little intraparticle diffusion me...
Novel (Ca, Mg)CO3&SiO2 NPs-decorated multilayer graphene sheets could be successfully prepared fr... more Novel (Ca, Mg)CO3&SiO2 NPs-decorated multilayer graphene sheets could be successfully prepared from corn stalk pith using a simple alkaline hydrothermal treatment process followed by calcination in an inert atmosphere. The produced nanocomposite was characterized by SEM, EDX, TEM, FTIR, and XRD analytical techniques, which confirm the formation of multilayer graphene sheets decorated by inorganic nanoparticles. The nanocomposite shows efficient activity as a photocatalyst for water-splitting reactions under visible light. The influence of preparation parameter variations, including the alkaline solution concentration, hydrothermal temperature, reaction time, and calcination temperature, on the hydrogen evolution rate was investigated by preparing many samples at different conditions. The experimental work indicated that treatment of the corn stalk pith hydrothermally by 1.0 M KOH solution at 170 °C for 3 h and calcinating the obtained solid at 600 °C results in the maximum hydrogen ...
Acid Yellow 36 (AY36) dye is a synthetic azo dye that is excessively used in various industries, ... more Acid Yellow 36 (AY36) dye is a synthetic azo dye that is excessively used in various industries, causing hazardous environmental effects. The main target of this study is the preparation of self-N-doped porous activated carbon (NDAC) and the investigation in eliminating the AY36 dye from the water solution. The NDAC was prepared by mixing fish waste (60% protein content) which was considered a self-nitrogen dopant. A combination of Fish waste, sawdust, zinc chloride and urea with a mass ratio (5:5:5:1) was submitted to hydrothermal process at 180 °C for 5 h followed by pyrolysis for 1 h under N2 stream at 600, 700, and 800 °C. Fabricated NDAC was qualified as an adsorbent for recovering AY36 dye from water using batch trials. The fabricated NDAC samples were characterized by FTIR, TGA, DTA, BET, BJH, MP, t-plot, SEM, EDX, and XRD methods. The results showed the successful formation of NDAC with nitrogen mass percentage content (4.21, 8.13 and 9.85%). The NDAC prepared at 800 °C had ...
The biomass, which converted into alternative fuel, has become an attractive source of renewable ... more The biomass, which converted into alternative fuel, has become an attractive source of renewable energy because of the shortage and high prices of fossil fuels. The bio -energy is now accepted as having the potential to provide the major part of the projected renewable energy in the future. Pyrolysis is one of the three main thermal paths, along with gasification and combustion, for providing useful and valuable bio-fuel. The present work will consider Jatropha curcas seeds as the biomass source because Jatropha seeds have high energy bearing seeds available in nature. The fast pyrolysis of Jatropha was carried out in a fixed bed batch reactor made up of stainless steel at a temperature ranging from 400oC to 550oC to produce liquid biofuel at an interval of 50oC. The effect of temperature on the fast pyrolysis of the material is studied to know the optimum temperature for maximum liquid yield. The thermal degradation of the Jatropha seed was studied using thermogravimetric analysis ...
The inhibition efficiency (IE) of the hydrochloride salt of chitosan biguanidine (CBG-HCl, a gree... more The inhibition efficiency (IE) of the hydrochloride salt of chitosan biguanidine (CBG-HCl, a green organic compound) on stainless steel alloy (SS) corrosion in 0.5 M H2SO4 solution was documented in this work. Data reported for electrochemical impedance spectroscopy (EIS) and potentiodynamic analysis confirmed increasing of the corrosion resistance of stainless steel in 0.5 M H2SO4 solution in the presence of CBG-HCl with a synergistic effect of KI. Potentiodynamic experiments also indicate that the blend of CBG-HCl-KI works as a mixed-type inhibitor for stainless steel alloy corrosion. The best information gathered agreed with the Langmuir isotherm model. The corresponding normal Gibbs inhibitor adsorption free energy implied that the processes are random and involved two forms of interactions, chemisorption and physisorption. The highest inhibition efficiency (88 %) in this work was reported for 400 ppm of CBG-HCl blended with 800 ppm KI. In fact, with a long immersion time, the efficiency of CBG-HCl inhibition remains effectively high, demonstrating its good stability in the 0.5 M H2SO4 medium.
International Journal of Bioscience, Biochemistry and Bioinformatics, 2018
The aim of this work to propose a stable and easy technique to analyze urine based on graphene Na... more The aim of this work to propose a stable and easy technique to analyze urine based on graphene Nano sheet. Where graphene Nano sheets used as a detector and as well as the rate of electrons transfer into the detector. As a result, the characteristic surface conductivity of graphene makes it a super conductor in a very small size. Urea measurement in urine and blood related to many diseases such as kidney and liver diseases. Sensitive urea measurement in urine and blood really need super conductor graphene sensor which can read the concentration of urea and translate it to micro and milli ampere at specific voltage then compare them with a normal one. The graphene super conductor material is chemical inert which can read a very low concentration and make an accurate prediction of theses serious diseases without any effect on the results within a simple, it produces a stable and accurate performance.
This research aims to develop efficient process technologies that are capable of converting/utili... more This research aims to develop efficient process technologies that are capable of converting/utilising CO 2 streams into energy-rich liquid products (fuels). This would result in better solutions with near-zero-carbon-emissions level. From an energetic and economic point of view, methanol synthesis from CO 2 is a competitive alternate to methanol production from biomass. Our work considers the CO 2 balance for the technologies proposed, taking into account all CO 2 flows from/to the environment. Flue gas CO 2 streams released from electric power stations, steel industry, petroleum industry, and cement industry are good candidates for the developed technologies. Three new processes are developed and modelled for converting CO 2 streams into liquid methanol. The total cost of equipment and utility for all process scenarios are evaluated and compared. The energy targets as well as the CO 2 emissions (balance) are determined. Heat integration is performed on the best selected process technology. The case study employed for the present work is a power station plant burning natural gas for electricity production with a capacity of 112 MW, releasing 328 t/h flue gases to the atmosphere, of which CO 2 gas accounts for 14%; hydrogen required for CO 2 conversion comes from the chlor-alkali industry. The optimum process technology reached in this contribution results in methanol production of 0.625 t-per-tonne of CO 2 waste gas supply, leading to an annual production of 222,507 tons methanol with a profit of 56.55 M$/y. Thus, the CO 2 release to the environment is cut by about 62%.
Conventional fuels have severely impacted the environment; therefore, renewable sources are consi... more Conventional fuels have severely impacted the environment; therefore, renewable sources are considered a very good alternative to conventional ones. Fuel cells could be regarded to be an excellent alternative source of energy. Platinum and their alloys have long been considered as the perfect catalyst for oxygen reduction reaction in fuel cells at the current stage of this technology. Platinum is highly expensive for cathode catalyst, the objective of this work is to prepare and characterize catalyst as non-precious metallic nanostructures as novel, cheap and effective cathode catalysts for fuel cells. Cobalt-doped carbon nanofibers (Co-doped CNFs) as catalyst for cathode in fuel cell, has been prepared and characterized by using TEM and XRD measurements the oxygen electroreduction activity was studied by technique of cyclic voltammetry (CV), thus results indicated that (Co-doped CNFs) has high current density for the reduction in fuel cell where it is cobalt only not iron-cobalt or Platinum cobalt alloy so (Co-doped CNFs) has high oxygen reduction reaction (ORR) activity.
Natural clays have been recommended as a green alternative sorbent, with low cost, good mechanica... more Natural clays have been recommended as a green alternative sorbent, with low cost, good mechanical properties, and good tolerance to a harsh chemical environment. However, on a large scale, it is difficult to separate the clay particles from the solution; the centrifugation process involves a high speed, and the filtration procedure is prone to filter blockages. Therefore, a suitable method for the separation of clay particles is necessary to be found. To solve this problem, the clay should be modified. In this paper, attapulgite (ATP) as a natural clay was modified using double-layer hydroxide to produce LDH-ATP sorbent. Different sorption isotherm models of the modified attapulgite for the removal of Sr2+, Co2+, and Ni2+ ions from a multicomponent solution were evaluated, for instance, the extended Langmuir and Freundlich isotherm models. The results demonstrated that the extended Langmuir is more suitable than Freundlich isotherm (with R2 values greater than 0.95). The maximum ca...
This study aims to provide the technoeconomic aspects of two clean processes for biodiesel produc... more This study aims to provide the technoeconomic aspects of two clean processes for biodiesel production. The first process utilizes waste cooking oil as a feedstock and potassium hydroxide as a homogeneous catalyst. The second process uses cement kiln dust heterogeneous catalyst and virgin soybean oil. A comparison was performed between the results of the technical and economic assessments to determine the more feasible process. Theoretical purities of biodiesel and glycerol obtained upon conducting the simulation of both processes are high, i.e., 99.99%. However, the homogeneous process is economically superior as its payback period is slightly more than 1 year while the return on investment is higher than 74%, and the unit production cost is USD 1.067/kg biodiesel. Sensitivity analysis revealed that the profitability of biodiesel production is very sensitive to the feedstock price and recommends shifting toward waste vegetable oils as a cheap feedstock to have a feasible and economi...
International Journal of Innovative Technology and Exploring Engineering, 2020
Microbial electrolysis cells (MECs) are breakthrough technology of cheap hydrogen production with... more Microbial electrolysis cells (MECs) are breakthrough technology of cheap hydrogen production with high efficiency. In this paper differential-algebraic equation (DAE) model of a MEC with an algebraic constraint on current was studied, simulated and validated by implementing the model on continuous-flow MECs. Then sensitivity analysis for the system was effectuated. Parameters which have the predominating influence on the current density and hydrogen production rate were defined. This sensitivity analysis was utilized in modeling and validation of the batch-cycle of MEC. After that parameters which have less influence on MEC were eliminated and simplified reduced model was obtained and validated. Finally, MEC energy productivity was maximized by optimization of operating conditions.
... Immobilization may also enhance biosorption capacity and can overcome processing problems ari... more ... Immobilization may also enhance biosorption capacity and can overcome processing problems arising from using powder biomass which in most cases has low density and strength and becomes soft upon contact with water [42], [43], [44] and [45]. ...
Liquid-liquid equilibrium (LLE) data for four ternary systems comprising cyclohexane + (benzene, ... more Liquid-liquid equilibrium (LLE) data for four ternary systems comprising cyclohexane + (benzene, toluene, ethylbenzene, or cumene) + sulfolane have been measured at 303.15 K and at atmospheric pressure. The LLE data for a six-component system including (cyclohexane + benzene + toluene + ethylbenzene + cumene + sulfolane) has also been measured at the above conditions. The reliability of the experimental data was tested using the Othmer-Tobias correlation. The LLE data were then analyzed using a UNIFAC model with groupinteraction parameters extracted from the UNIFAC-LLE data bank and a NRTL version with temperature-dependent binary parameters determined from the experimental LLE data (NRTL/2), both as programmed by the Aspen Plus simulator. Based on the analysis of these data, both models represented the experimental data with sufficient accuracy as revealed from the very small values of the root mean square error and the average absolute deviation in composition.
Liquid-liquid equilibrium (LLE) data for the systems heptane + o-xylene + tetraethylene glycol (T... more Liquid-liquid equilibrium (LLE) data for the systems heptane + o-xylene + tetraethylene glycol (TTEG) have been experimentally studied over the temperature range (293 to 313) K. The experimental data of this work, in addition to 22 isothermal sets of LLE data (from the literature) for the extraction of aromatics from hydrocarbon mixtures using TTEG, are analyzed using two models. The models used are the empirical Othmer-Tobias correlation and the thermodynamic UNIQUAC model as programmed in the Aspen Plus simulator. For each data set, the analysis performed by the Othmer-Tobias correlation involves the determination of the model's parameters by regressing each set of data. The predictive capability of the UNIQUAC model has been investigated in terms of deviations for the mole fraction of the target aromatic species in the extract phase. Direct fitting of the data of this work using the Othmer-Tobias model gives an average rms (root-mean-square) of 0.002 in TTEG mass fraction in the extract phase, whereas prediction using UNIQUAC gives an average rms of 0.15.
Three cubic equations of state combined with different mixing rules are examined with regard to t... more Three cubic equations of state combined with different mixing rules are examined with regard to their Ž. prediction of solid-supercritical fluid equilibria SFE. The computed predictions are compared with experimental data. Results of the comparison are reported for highly asymmetric mixtures containing supercritical fluids such as carbon dioxide, ethane, ethylene, fluoroform or monochlorotrifluoromethane, and solid organic compounds such as acids, alcohols, and polynuclear aromatics. The experimental database of the comparison includes 41 binary systems covering a wide range of pressure and temperature. The same computational technique was used throughout this study. The results of this study indicate that the Estevez model, based on the Redlich-Kwong equation of state Ž. EOS , is superior in comparison with the other models. However, this model accurately correlates only the solubility of solids in SFs up to certain pressures and yields considerable deviations from experimental solubility data at high pressures. This is due to the fact that an infinite-dilution model would naturally get worse at higher solute concentrations and these will occur at higher pressures. For all equations examined, the predictions improved significantly for some systems, especially at temperatures near the critical point of the solvent, by incorporating the solute-solute interaction parameters that are based on the clusters formation in SF. It was also observed that incorporating additional parameters to the examined equations of state did not yield sufficient improvement of the predictions for some systems. This behavior may be due to the misleading solubility data or the formation of a liquid phase. To develop more adequate cubic equations of state andror mixing rules, the phase behavior and molecular interaction in supercritical solution should be understood. We therefore recommend quantitative molecular analysis.
Microbial fuel cells (MFCs) are a group of microbial electrochemical cells (bioreactors) that are... more Microbial fuel cells (MFCs) are a group of microbial electrochemical cells (bioreactors) that are used to generate energy from organic waste found in wastewater. MFCs represent a promising method of waste disposal and production of electricity. Scaling up the use of MFCs requires extensive analysis and detailed grasp of the required processes. The current work aimed to study a model of an MFC, and find the optimum parameters needed for maximum energy production. The process was simulated and validated on continuous-flow MFCs with a Columbic efficiency of 162% and 35% COD removal. Sensitivity analysis of the model was performed. The studied model was found to be valid for both batch-cycle and continuous-flow MFCs. Parameters with less influence on MFCs were eliminated in order to obtain a simplified model of MFC performance. The new simplified model was then validated. Finally, optimization of operating external resistance was conducted to maximize energy generation.
... Carbon Dioxide Experimental Measurements and Model Prediction IbrahimAshour* Department of Ch... more ... Carbon Dioxide Experimental Measurements and Model Prediction IbrahimAshour* Department of Chemical Engineering I, University of Lund, PO Box 124, S221 00 Lund, Sweden HagarHammam Department of ... Ohgaki, K.; Tsukahara, I.; Semba, K.; Katayama, T. ht.Chern. ...
This study investigates the activity of hydrochloride salt of chitosan biguanidine (CBG-HCl) as a... more This study investigates the activity of hydrochloride salt of chitosan biguanidine (CBG-HCl) as a green corrosion inhibitor of copper alloy in 0.5 M H 2 SO 4 solution. The obtained results from both the potentiodynamic and electrochemical impedance spectroscopy analyses reported a noticeable increase in the corrosion inhibition of copper alloy in 0.5 M H 2 SO 4 solution in the presence of CBG-HCl. The presence of CBG-HCl in the corrosive solution may block the copper alloy's pores on the outer surface, preventing the corrosive gradients from reacting with the surface of the copper alloy. An inhibition efficiency (IE) of 85% is achieved in the presence of 200 ppm CBG-HCl. Moreover, potentiodynamic experiments indicated that CBG-HCl acted as an anodic inhibitor that reduced partial anodic reaction to corrosion of studied copper alloy in 0.5 M H 2 SO 4. IE of CBG-HCl remains effective during a long exposure time which proved the high stability of CBG-HCl inhibitor in 0.5 M H 2 SO 4 .
Adsorption of benzene, naphtalene, anthracene, and phenanthrene at the aqueous surface is investi... more Adsorption of benzene, naphtalene, anthracene, and phenanthrene at the aqueous surface is investigated by means of molecular dynamics simulations. Potentials of mean force, i.e., free energy profiles of moving the studied molecules across an aqueous slab were evaluated. In all cases, deep surface free energy minima, corresponding to orders of magnitude of surface enhancement of the aromatic molecule, were located. This enhancement, which increases with the size of the solute, points to the importance of the aqueous surface for the chemistry of polycyclic aromatic hydrocarbons (PAHs). Supporting evidence in the atmospheric environment related to the heterogeneous chemistry of PAHs on water droplets and planar surfaces is summarized. There is good agreement between the hydration free energies computed from MD calculations and the experimentally determined values. Data pertaining to the importance of air/water interface in the adsorption and transport of PAHs on micron sized water droplets are described. The relevant data on adsorption and reaction (ozonation and photochemical) at the air/water interface of planar surfaces and droplets are also summarized.
A modified Camahan-Starling-Soave equation-of-state (MCSV-EOS) with a temperature-dependent a par... more A modified Camahan-Starling-Soave equation-of-state (MCSV-EOS) with a temperature-dependent a parameter has been evaluated to enable the vapor pressures of saturated fatty acids to be predicted. The co-volume parameter, b, has been evaluated for both the temperature-...
The efficacy of using blank alginate beads and immobilized dead algal cells for the removal of zi... more The efficacy of using blank alginate beads and immobilized dead algal cells for the removal of zinc ions from aqueous solutions was investigated. It was found that the sorption capacities were significantly affected by solution pH; with higher pH favoring higher zinc ion uptake. Dynamics and isotherm experiments were carried out at the optimal pH 5.0. Zinc uptake on either sorbent was found to be rapid where approximately 90% of the maximum zinc uptake occurred within the first 30 min in both cases of blank alginate and immobilized algal cells. The equilibrium data for the biosorption of zinc ions onto both sorbents were fitted to the Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm equations. The presence of copper and nickel in aqueous solutions was found to suppress the sorption process. The results of the dynamics studies revealed that the biosorption of zinc on immobilized dead algal cells followed pseudo-second order kinetics with little intraparticle diffusion me...
Novel (Ca, Mg)CO3&SiO2 NPs-decorated multilayer graphene sheets could be successfully prepared fr... more Novel (Ca, Mg)CO3&SiO2 NPs-decorated multilayer graphene sheets could be successfully prepared from corn stalk pith using a simple alkaline hydrothermal treatment process followed by calcination in an inert atmosphere. The produced nanocomposite was characterized by SEM, EDX, TEM, FTIR, and XRD analytical techniques, which confirm the formation of multilayer graphene sheets decorated by inorganic nanoparticles. The nanocomposite shows efficient activity as a photocatalyst for water-splitting reactions under visible light. The influence of preparation parameter variations, including the alkaline solution concentration, hydrothermal temperature, reaction time, and calcination temperature, on the hydrogen evolution rate was investigated by preparing many samples at different conditions. The experimental work indicated that treatment of the corn stalk pith hydrothermally by 1.0 M KOH solution at 170 °C for 3 h and calcinating the obtained solid at 600 °C results in the maximum hydrogen ...
Acid Yellow 36 (AY36) dye is a synthetic azo dye that is excessively used in various industries, ... more Acid Yellow 36 (AY36) dye is a synthetic azo dye that is excessively used in various industries, causing hazardous environmental effects. The main target of this study is the preparation of self-N-doped porous activated carbon (NDAC) and the investigation in eliminating the AY36 dye from the water solution. The NDAC was prepared by mixing fish waste (60% protein content) which was considered a self-nitrogen dopant. A combination of Fish waste, sawdust, zinc chloride and urea with a mass ratio (5:5:5:1) was submitted to hydrothermal process at 180 °C for 5 h followed by pyrolysis for 1 h under N2 stream at 600, 700, and 800 °C. Fabricated NDAC was qualified as an adsorbent for recovering AY36 dye from water using batch trials. The fabricated NDAC samples were characterized by FTIR, TGA, DTA, BET, BJH, MP, t-plot, SEM, EDX, and XRD methods. The results showed the successful formation of NDAC with nitrogen mass percentage content (4.21, 8.13 and 9.85%). The NDAC prepared at 800 °C had ...
The biomass, which converted into alternative fuel, has become an attractive source of renewable ... more The biomass, which converted into alternative fuel, has become an attractive source of renewable energy because of the shortage and high prices of fossil fuels. The bio -energy is now accepted as having the potential to provide the major part of the projected renewable energy in the future. Pyrolysis is one of the three main thermal paths, along with gasification and combustion, for providing useful and valuable bio-fuel. The present work will consider Jatropha curcas seeds as the biomass source because Jatropha seeds have high energy bearing seeds available in nature. The fast pyrolysis of Jatropha was carried out in a fixed bed batch reactor made up of stainless steel at a temperature ranging from 400oC to 550oC to produce liquid biofuel at an interval of 50oC. The effect of temperature on the fast pyrolysis of the material is studied to know the optimum temperature for maximum liquid yield. The thermal degradation of the Jatropha seed was studied using thermogravimetric analysis ...
The inhibition efficiency (IE) of the hydrochloride salt of chitosan biguanidine (CBG-HCl, a gree... more The inhibition efficiency (IE) of the hydrochloride salt of chitosan biguanidine (CBG-HCl, a green organic compound) on stainless steel alloy (SS) corrosion in 0.5 M H2SO4 solution was documented in this work. Data reported for electrochemical impedance spectroscopy (EIS) and potentiodynamic analysis confirmed increasing of the corrosion resistance of stainless steel in 0.5 M H2SO4 solution in the presence of CBG-HCl with a synergistic effect of KI. Potentiodynamic experiments also indicate that the blend of CBG-HCl-KI works as a mixed-type inhibitor for stainless steel alloy corrosion. The best information gathered agreed with the Langmuir isotherm model. The corresponding normal Gibbs inhibitor adsorption free energy implied that the processes are random and involved two forms of interactions, chemisorption and physisorption. The highest inhibition efficiency (88 %) in this work was reported for 400 ppm of CBG-HCl blended with 800 ppm KI. In fact, with a long immersion time, the efficiency of CBG-HCl inhibition remains effectively high, demonstrating its good stability in the 0.5 M H2SO4 medium.
International Journal of Bioscience, Biochemistry and Bioinformatics, 2018
The aim of this work to propose a stable and easy technique to analyze urine based on graphene Na... more The aim of this work to propose a stable and easy technique to analyze urine based on graphene Nano sheet. Where graphene Nano sheets used as a detector and as well as the rate of electrons transfer into the detector. As a result, the characteristic surface conductivity of graphene makes it a super conductor in a very small size. Urea measurement in urine and blood related to many diseases such as kidney and liver diseases. Sensitive urea measurement in urine and blood really need super conductor graphene sensor which can read the concentration of urea and translate it to micro and milli ampere at specific voltage then compare them with a normal one. The graphene super conductor material is chemical inert which can read a very low concentration and make an accurate prediction of theses serious diseases without any effect on the results within a simple, it produces a stable and accurate performance.
This research aims to develop efficient process technologies that are capable of converting/utili... more This research aims to develop efficient process technologies that are capable of converting/utilising CO 2 streams into energy-rich liquid products (fuels). This would result in better solutions with near-zero-carbon-emissions level. From an energetic and economic point of view, methanol synthesis from CO 2 is a competitive alternate to methanol production from biomass. Our work considers the CO 2 balance for the technologies proposed, taking into account all CO 2 flows from/to the environment. Flue gas CO 2 streams released from electric power stations, steel industry, petroleum industry, and cement industry are good candidates for the developed technologies. Three new processes are developed and modelled for converting CO 2 streams into liquid methanol. The total cost of equipment and utility for all process scenarios are evaluated and compared. The energy targets as well as the CO 2 emissions (balance) are determined. Heat integration is performed on the best selected process technology. The case study employed for the present work is a power station plant burning natural gas for electricity production with a capacity of 112 MW, releasing 328 t/h flue gases to the atmosphere, of which CO 2 gas accounts for 14%; hydrogen required for CO 2 conversion comes from the chlor-alkali industry. The optimum process technology reached in this contribution results in methanol production of 0.625 t-per-tonne of CO 2 waste gas supply, leading to an annual production of 222,507 tons methanol with a profit of 56.55 M$/y. Thus, the CO 2 release to the environment is cut by about 62%.
Conventional fuels have severely impacted the environment; therefore, renewable sources are consi... more Conventional fuels have severely impacted the environment; therefore, renewable sources are considered a very good alternative to conventional ones. Fuel cells could be regarded to be an excellent alternative source of energy. Platinum and their alloys have long been considered as the perfect catalyst for oxygen reduction reaction in fuel cells at the current stage of this technology. Platinum is highly expensive for cathode catalyst, the objective of this work is to prepare and characterize catalyst as non-precious metallic nanostructures as novel, cheap and effective cathode catalysts for fuel cells. Cobalt-doped carbon nanofibers (Co-doped CNFs) as catalyst for cathode in fuel cell, has been prepared and characterized by using TEM and XRD measurements the oxygen electroreduction activity was studied by technique of cyclic voltammetry (CV), thus results indicated that (Co-doped CNFs) has high current density for the reduction in fuel cell where it is cobalt only not iron-cobalt or Platinum cobalt alloy so (Co-doped CNFs) has high oxygen reduction reaction (ORR) activity.
Natural clays have been recommended as a green alternative sorbent, with low cost, good mechanica... more Natural clays have been recommended as a green alternative sorbent, with low cost, good mechanical properties, and good tolerance to a harsh chemical environment. However, on a large scale, it is difficult to separate the clay particles from the solution; the centrifugation process involves a high speed, and the filtration procedure is prone to filter blockages. Therefore, a suitable method for the separation of clay particles is necessary to be found. To solve this problem, the clay should be modified. In this paper, attapulgite (ATP) as a natural clay was modified using double-layer hydroxide to produce LDH-ATP sorbent. Different sorption isotherm models of the modified attapulgite for the removal of Sr2+, Co2+, and Ni2+ ions from a multicomponent solution were evaluated, for instance, the extended Langmuir and Freundlich isotherm models. The results demonstrated that the extended Langmuir is more suitable than Freundlich isotherm (with R2 values greater than 0.95). The maximum ca...
This study aims to provide the technoeconomic aspects of two clean processes for biodiesel produc... more This study aims to provide the technoeconomic aspects of two clean processes for biodiesel production. The first process utilizes waste cooking oil as a feedstock and potassium hydroxide as a homogeneous catalyst. The second process uses cement kiln dust heterogeneous catalyst and virgin soybean oil. A comparison was performed between the results of the technical and economic assessments to determine the more feasible process. Theoretical purities of biodiesel and glycerol obtained upon conducting the simulation of both processes are high, i.e., 99.99%. However, the homogeneous process is economically superior as its payback period is slightly more than 1 year while the return on investment is higher than 74%, and the unit production cost is USD 1.067/kg biodiesel. Sensitivity analysis revealed that the profitability of biodiesel production is very sensitive to the feedstock price and recommends shifting toward waste vegetable oils as a cheap feedstock to have a feasible and economi...
International Journal of Innovative Technology and Exploring Engineering, 2020
Microbial electrolysis cells (MECs) are breakthrough technology of cheap hydrogen production with... more Microbial electrolysis cells (MECs) are breakthrough technology of cheap hydrogen production with high efficiency. In this paper differential-algebraic equation (DAE) model of a MEC with an algebraic constraint on current was studied, simulated and validated by implementing the model on continuous-flow MECs. Then sensitivity analysis for the system was effectuated. Parameters which have the predominating influence on the current density and hydrogen production rate were defined. This sensitivity analysis was utilized in modeling and validation of the batch-cycle of MEC. After that parameters which have less influence on MEC were eliminated and simplified reduced model was obtained and validated. Finally, MEC energy productivity was maximized by optimization of operating conditions.
... Immobilization may also enhance biosorption capacity and can overcome processing problems ari... more ... Immobilization may also enhance biosorption capacity and can overcome processing problems arising from using powder biomass which in most cases has low density and strength and becomes soft upon contact with water [42], [43], [44] and [45]. ...
Liquid-liquid equilibrium (LLE) data for four ternary systems comprising cyclohexane + (benzene, ... more Liquid-liquid equilibrium (LLE) data for four ternary systems comprising cyclohexane + (benzene, toluene, ethylbenzene, or cumene) + sulfolane have been measured at 303.15 K and at atmospheric pressure. The LLE data for a six-component system including (cyclohexane + benzene + toluene + ethylbenzene + cumene + sulfolane) has also been measured at the above conditions. The reliability of the experimental data was tested using the Othmer-Tobias correlation. The LLE data were then analyzed using a UNIFAC model with groupinteraction parameters extracted from the UNIFAC-LLE data bank and a NRTL version with temperature-dependent binary parameters determined from the experimental LLE data (NRTL/2), both as programmed by the Aspen Plus simulator. Based on the analysis of these data, both models represented the experimental data with sufficient accuracy as revealed from the very small values of the root mean square error and the average absolute deviation in composition.
Liquid-liquid equilibrium (LLE) data for the systems heptane + o-xylene + tetraethylene glycol (T... more Liquid-liquid equilibrium (LLE) data for the systems heptane + o-xylene + tetraethylene glycol (TTEG) have been experimentally studied over the temperature range (293 to 313) K. The experimental data of this work, in addition to 22 isothermal sets of LLE data (from the literature) for the extraction of aromatics from hydrocarbon mixtures using TTEG, are analyzed using two models. The models used are the empirical Othmer-Tobias correlation and the thermodynamic UNIQUAC model as programmed in the Aspen Plus simulator. For each data set, the analysis performed by the Othmer-Tobias correlation involves the determination of the model's parameters by regressing each set of data. The predictive capability of the UNIQUAC model has been investigated in terms of deviations for the mole fraction of the target aromatic species in the extract phase. Direct fitting of the data of this work using the Othmer-Tobias model gives an average rms (root-mean-square) of 0.002 in TTEG mass fraction in the extract phase, whereas prediction using UNIQUAC gives an average rms of 0.15.
Three cubic equations of state combined with different mixing rules are examined with regard to t... more Three cubic equations of state combined with different mixing rules are examined with regard to their Ž. prediction of solid-supercritical fluid equilibria SFE. The computed predictions are compared with experimental data. Results of the comparison are reported for highly asymmetric mixtures containing supercritical fluids such as carbon dioxide, ethane, ethylene, fluoroform or monochlorotrifluoromethane, and solid organic compounds such as acids, alcohols, and polynuclear aromatics. The experimental database of the comparison includes 41 binary systems covering a wide range of pressure and temperature. The same computational technique was used throughout this study. The results of this study indicate that the Estevez model, based on the Redlich-Kwong equation of state Ž. EOS , is superior in comparison with the other models. However, this model accurately correlates only the solubility of solids in SFs up to certain pressures and yields considerable deviations from experimental solubility data at high pressures. This is due to the fact that an infinite-dilution model would naturally get worse at higher solute concentrations and these will occur at higher pressures. For all equations examined, the predictions improved significantly for some systems, especially at temperatures near the critical point of the solvent, by incorporating the solute-solute interaction parameters that are based on the clusters formation in SF. It was also observed that incorporating additional parameters to the examined equations of state did not yield sufficient improvement of the predictions for some systems. This behavior may be due to the misleading solubility data or the formation of a liquid phase. To develop more adequate cubic equations of state andror mixing rules, the phase behavior and molecular interaction in supercritical solution should be understood. We therefore recommend quantitative molecular analysis.
Microbial fuel cells (MFCs) are a group of microbial electrochemical cells (bioreactors) that are... more Microbial fuel cells (MFCs) are a group of microbial electrochemical cells (bioreactors) that are used to generate energy from organic waste found in wastewater. MFCs represent a promising method of waste disposal and production of electricity. Scaling up the use of MFCs requires extensive analysis and detailed grasp of the required processes. The current work aimed to study a model of an MFC, and find the optimum parameters needed for maximum energy production. The process was simulated and validated on continuous-flow MFCs with a Columbic efficiency of 162% and 35% COD removal. Sensitivity analysis of the model was performed. The studied model was found to be valid for both batch-cycle and continuous-flow MFCs. Parameters with less influence on MFCs were eliminated in order to obtain a simplified model of MFC performance. The new simplified model was then validated. Finally, optimization of operating external resistance was conducted to maximize energy generation.
... Carbon Dioxide Experimental Measurements and Model Prediction IbrahimAshour* Department of Ch... more ... Carbon Dioxide Experimental Measurements and Model Prediction IbrahimAshour* Department of Chemical Engineering I, University of Lund, PO Box 124, S221 00 Lund, Sweden HagarHammam Department of ... Ohgaki, K.; Tsukahara, I.; Semba, K.; Katayama, T. ht.Chern. ...
This study investigates the activity of hydrochloride salt of chitosan biguanidine (CBG-HCl) as a... more This study investigates the activity of hydrochloride salt of chitosan biguanidine (CBG-HCl) as a green corrosion inhibitor of copper alloy in 0.5 M H 2 SO 4 solution. The obtained results from both the potentiodynamic and electrochemical impedance spectroscopy analyses reported a noticeable increase in the corrosion inhibition of copper alloy in 0.5 M H 2 SO 4 solution in the presence of CBG-HCl. The presence of CBG-HCl in the corrosive solution may block the copper alloy's pores on the outer surface, preventing the corrosive gradients from reacting with the surface of the copper alloy. An inhibition efficiency (IE) of 85% is achieved in the presence of 200 ppm CBG-HCl. Moreover, potentiodynamic experiments indicated that CBG-HCl acted as an anodic inhibitor that reduced partial anodic reaction to corrosion of studied copper alloy in 0.5 M H 2 SO 4. IE of CBG-HCl remains effective during a long exposure time which proved the high stability of CBG-HCl inhibitor in 0.5 M H 2 SO 4 .
Adsorption of benzene, naphtalene, anthracene, and phenanthrene at the aqueous surface is investi... more Adsorption of benzene, naphtalene, anthracene, and phenanthrene at the aqueous surface is investigated by means of molecular dynamics simulations. Potentials of mean force, i.e., free energy profiles of moving the studied molecules across an aqueous slab were evaluated. In all cases, deep surface free energy minima, corresponding to orders of magnitude of surface enhancement of the aromatic molecule, were located. This enhancement, which increases with the size of the solute, points to the importance of the aqueous surface for the chemistry of polycyclic aromatic hydrocarbons (PAHs). Supporting evidence in the atmospheric environment related to the heterogeneous chemistry of PAHs on water droplets and planar surfaces is summarized. There is good agreement between the hydration free energies computed from MD calculations and the experimentally determined values. Data pertaining to the importance of air/water interface in the adsorption and transport of PAHs on micron sized water droplets are described. The relevant data on adsorption and reaction (ozonation and photochemical) at the air/water interface of planar surfaces and droplets are also summarized.
A modified Camahan-Starling-Soave equation-of-state (MCSV-EOS) with a temperature-dependent a par... more A modified Camahan-Starling-Soave equation-of-state (MCSV-EOS) with a temperature-dependent a parameter has been evaluated to enable the vapor pressures of saturated fatty acids to be predicted. The co-volume parameter, b, has been evaluated for both the temperature-...
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