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Papers by Jamal Chaouki
Chemical Engineering Science, 2022
Korean Journal of Chemical Engineering, Jul 1, 1999
Turbulent Fluidized Bed (TFB) reactors appears to be ideal for exothermic and fast reactions such... more Turbulent Fluidized Bed (TFB) reactors appears to be ideal for exothermic and fast reactions such as catalytic oxidation of methane. In this paper, a use of TFB reactor for two catalytic oxidation of methane: catalytic combustion of methane and catalytic selective oxidation of methane for the ethylene synthesis is described. Catalytic fluidized bed combustion of methane is shown to be an emerging technology capable of meeting all environmental constraints as far as nitrogen oxides and carbon monoxide are concerned. This reaction carried out in both the bubbling and the turbulent regimes at 450-500 ‡C shows that the turbulent regime is more favourable. A self-sustained combustion with complete conversion and a zero emission of NOx and CO was achieved with a mixture of 4% methane in air at 500 ‡C. The two-phase model of Werther [1990], which phenomenologically introduces the enhancement factor due to chemical reaction, predicts quite well the combustor performance. The same model but without enhancement factor (slower reactions) predicts satisfactorily the experimental data for the oxidative coupling of methane and can be used to quantify the influence of homogeneous and catalytic reactions.
Chemical Engineering Science, 1994
Chemical Engineering Communications, Jul 1, 1993
A new application of the fixed bed catalytic reactor with flow reversal for combustion of natural... more A new application of the fixed bed catalytic reactor with flow reversal for combustion of natural gas is investigated by mathematical modeling and computer simulation. Comparison between the results obtained for this new reactor and those for a classic catalytic fixed bed is made. Inexpensive perovskite type catalysts containing no noble metals were used. It is shown that an appropriate
Canadian Journal of Chemical Engineering, May 19, 2008
The combustion of methane was studied in a fixed bed reactor to determine the effect of inert par... more The combustion of methane was studied in a fixed bed reactor to determine the effect of inert particles through heterogeneous and homogeneous reactions. Methane and CO2 mole fractions are measured at the reactor outlet. The results show that any accelerating catalytic effect of the inert particles is quite small, while considerable inhibition effect was found at moderately high temperatures. A plug flow model with a complete and reduced reaction scheme was developed to explain the experimental findings. Both reaction schemes fail to fully predict the experimental data. Therefore, an improved combined mechanism is proposed, which is now able to predict the experimental data.
Chemical Engineering Science, 2020
Chemical Engineering and Processing - Process Intensification, 2018
Chemical Engineering Science, 2018
AIChE Journal, 2015
The effects of liquid phase rheology on the local hydrodynamics of bubble column reactors operati... more The effects of liquid phase rheology on the local hydrodynamics of bubble column reactors operating with non-Newtonian liquids are investigated. Local bubble properties, including bubble frequency, bubble chord length, and bubble rise velocity, are measured by placing two in-house made optical fiber probes at various locations within a bubble column reactor operating with different non-Newtonian liquids. It was found that the presence of elasticity can noticeably increase the bubble frequency but decreases the bubble chord length and its rise velocity. The radial profiles of bubble frequency, bubble chord length, and bubble rise velocity are shown to be relatively flat at low superficial gas velocity while they become parabolic at high superficial gas velocity. Moreover, the bubble size and gas holdup are correlated with respect to dimensionless groups by considering the ratio between dynamic moduli of viscoelastic liquids. The novel proposed correlations are capable of predicting the experimental data of bubble size and gas holdup within a mean absolute percentage error of 9.3% and 10%, respectively. © 2015 American Institute of Chemical Engineers AIChE J, 62: 1382–1396, 2016
Chemical Engineering Journal, 2016
Green Chem., 2016
Lignin can be converted by pyrolysis, supercritical rectification, and methylation, into an aroma... more Lignin can be converted by pyrolysis, supercritical rectification, and methylation, into an aromatic bio-derived solvent.
Advances in Multiphase Flow and Heat Transfer (Volume 3), 2012
The Canadian Journal of Chemical Engineering, 2018
Differential calorimetry assesses energy flow between a sample and its environment. The sample ma... more Differential calorimetry assesses energy flow between a sample and its environment. The sample may be heated at a known heating rate (either constant or temperature modulated), or held in an isothermal environment or adiabatic environment depending on instrument and experimental design. The subset of differential calorimetry that deals with known heating or cooling rates is termed differential scanning calorimetry (DSC) and is a foundational technique to modern thermodynamics. It reports the heat flow versus temperature or time from which we calculate specific heat capacity at constant pressure, , enthalpy of fusion, and the heat of reaction. Moreover, it identifies how microstuctural properties evolve and thermal arrests—a characteristic of phase transitions. Heat‐flux DSCs measure the temperature difference between a reference and a sample that sit on a thin two‐dimensional plate. Power compensated DSCs heat reference material and the sample in independent furnaces while maintaini...
Frontiers in Chemical Engineering
Microwave (MW) heating is rapid, selective, and volumetric, and it is a compelling non-convention... more Microwave (MW) heating is rapid, selective, and volumetric, and it is a compelling non-conventional heating approach for driving chemical reactions. The effect of MW irradiation on the kinetics of thermal/catalytic reactions is still under debate. A group of researchers reported that the effect of MW heating on reaction kinetics is highlighted through the non-thermal effects of MWs on kinetic parameters and reaction mechanisms in addition to the thermal effect. However, another group attributed the observations to the thermal effect only. In the present work, we summarized and critically synthesized available information in the literature on the subject. It can be concluded that MW heating has solely the thermal effect on gas-solid reactions, and the variations of kinetic parameters are related to the direct and indirect impacts of that. Temperature measurement limitations, physical structure variation, and non-uniform temperature distribution are the primary sources of the discrepa...
RSC Advances
The developed two-step protocol offers a superior reduced graphene oxide TCRGOL quality (7 layers... more The developed two-step protocol offers a superior reduced graphene oxide TCRGOL quality (7 layers), and its SET was 94 dB over the X-band.
Journal of Chemical and Petroleum Engineering, 2018
Temperature measurement in microwave systems is essential for thermally driven processes, namely,... more Temperature measurement in microwave systems is essential for thermally driven processes, namely, catalytic reactions and ceramic sintering. Although, the application of direct thermometry methods, namely, thermocouples, have been commonly articulated in the available literature, however, contacted temperature measurement mechanisms have aroused concerns associated with the disruption of the electromagnetic field and local distortion of the field pattern leading to unprecedented measurement uncertainties. Consequently, the application of optical measurement methods has been advocated to diminish the associated concerns. However, due to the economical constrains and measurement range restrictions, the application of optical measurement systems, namely, pyrometers and optical fibers, has been deferred. In this study, an infrared thermopile, a precise and feasible temperature measurement system has been developed and calibrated to perform in microwave irradiation. Furthermore, the accu...
Authors developed a novel pulsation-assisted technic to effectively fluidize the nanoparticles of... more Authors developed a novel pulsation-assisted technic to effectively fluidize the nanoparticles of different types. The developed fluidization technic was primarily investigated inside a transparent tube with 2.5 cm diameter and 20 cm height. A solenoid valve was located in the reactor outlet to switch between ON and OFF positions to intermittently pressurize the gas inside the reactor and then let it exit. Two differential pressure transducers and a high-speed camera recorded the pressure fluctuations of the bed. Superficial gas velocity and intermittence frequency of the solenoid valve were varied to investigate fluidization quality. An experimental procedure was developed to estimate the maximum amount of interparticle forces between the nanoparticles in the bed.
Chemical Engineering Science, 2022
Korean Journal of Chemical Engineering, Jul 1, 1999
Turbulent Fluidized Bed (TFB) reactors appears to be ideal for exothermic and fast reactions such... more Turbulent Fluidized Bed (TFB) reactors appears to be ideal for exothermic and fast reactions such as catalytic oxidation of methane. In this paper, a use of TFB reactor for two catalytic oxidation of methane: catalytic combustion of methane and catalytic selective oxidation of methane for the ethylene synthesis is described. Catalytic fluidized bed combustion of methane is shown to be an emerging technology capable of meeting all environmental constraints as far as nitrogen oxides and carbon monoxide are concerned. This reaction carried out in both the bubbling and the turbulent regimes at 450-500 ‡C shows that the turbulent regime is more favourable. A self-sustained combustion with complete conversion and a zero emission of NOx and CO was achieved with a mixture of 4% methane in air at 500 ‡C. The two-phase model of Werther [1990], which phenomenologically introduces the enhancement factor due to chemical reaction, predicts quite well the combustor performance. The same model but without enhancement factor (slower reactions) predicts satisfactorily the experimental data for the oxidative coupling of methane and can be used to quantify the influence of homogeneous and catalytic reactions.
Chemical Engineering Science, 1994
Chemical Engineering Communications, Jul 1, 1993
A new application of the fixed bed catalytic reactor with flow reversal for combustion of natural... more A new application of the fixed bed catalytic reactor with flow reversal for combustion of natural gas is investigated by mathematical modeling and computer simulation. Comparison between the results obtained for this new reactor and those for a classic catalytic fixed bed is made. Inexpensive perovskite type catalysts containing no noble metals were used. It is shown that an appropriate
Canadian Journal of Chemical Engineering, May 19, 2008
The combustion of methane was studied in a fixed bed reactor to determine the effect of inert par... more The combustion of methane was studied in a fixed bed reactor to determine the effect of inert particles through heterogeneous and homogeneous reactions. Methane and CO2 mole fractions are measured at the reactor outlet. The results show that any accelerating catalytic effect of the inert particles is quite small, while considerable inhibition effect was found at moderately high temperatures. A plug flow model with a complete and reduced reaction scheme was developed to explain the experimental findings. Both reaction schemes fail to fully predict the experimental data. Therefore, an improved combined mechanism is proposed, which is now able to predict the experimental data.
Chemical Engineering Science, 2020
Chemical Engineering and Processing - Process Intensification, 2018
Chemical Engineering Science, 2018
AIChE Journal, 2015
The effects of liquid phase rheology on the local hydrodynamics of bubble column reactors operati... more The effects of liquid phase rheology on the local hydrodynamics of bubble column reactors operating with non-Newtonian liquids are investigated. Local bubble properties, including bubble frequency, bubble chord length, and bubble rise velocity, are measured by placing two in-house made optical fiber probes at various locations within a bubble column reactor operating with different non-Newtonian liquids. It was found that the presence of elasticity can noticeably increase the bubble frequency but decreases the bubble chord length and its rise velocity. The radial profiles of bubble frequency, bubble chord length, and bubble rise velocity are shown to be relatively flat at low superficial gas velocity while they become parabolic at high superficial gas velocity. Moreover, the bubble size and gas holdup are correlated with respect to dimensionless groups by considering the ratio between dynamic moduli of viscoelastic liquids. The novel proposed correlations are capable of predicting the experimental data of bubble size and gas holdup within a mean absolute percentage error of 9.3% and 10%, respectively. © 2015 American Institute of Chemical Engineers AIChE J, 62: 1382–1396, 2016
Chemical Engineering Journal, 2016
Green Chem., 2016
Lignin can be converted by pyrolysis, supercritical rectification, and methylation, into an aroma... more Lignin can be converted by pyrolysis, supercritical rectification, and methylation, into an aromatic bio-derived solvent.
Advances in Multiphase Flow and Heat Transfer (Volume 3), 2012
The Canadian Journal of Chemical Engineering, 2018
Differential calorimetry assesses energy flow between a sample and its environment. The sample ma... more Differential calorimetry assesses energy flow between a sample and its environment. The sample may be heated at a known heating rate (either constant or temperature modulated), or held in an isothermal environment or adiabatic environment depending on instrument and experimental design. The subset of differential calorimetry that deals with known heating or cooling rates is termed differential scanning calorimetry (DSC) and is a foundational technique to modern thermodynamics. It reports the heat flow versus temperature or time from which we calculate specific heat capacity at constant pressure, , enthalpy of fusion, and the heat of reaction. Moreover, it identifies how microstuctural properties evolve and thermal arrests—a characteristic of phase transitions. Heat‐flux DSCs measure the temperature difference between a reference and a sample that sit on a thin two‐dimensional plate. Power compensated DSCs heat reference material and the sample in independent furnaces while maintaini...
Frontiers in Chemical Engineering
Microwave (MW) heating is rapid, selective, and volumetric, and it is a compelling non-convention... more Microwave (MW) heating is rapid, selective, and volumetric, and it is a compelling non-conventional heating approach for driving chemical reactions. The effect of MW irradiation on the kinetics of thermal/catalytic reactions is still under debate. A group of researchers reported that the effect of MW heating on reaction kinetics is highlighted through the non-thermal effects of MWs on kinetic parameters and reaction mechanisms in addition to the thermal effect. However, another group attributed the observations to the thermal effect only. In the present work, we summarized and critically synthesized available information in the literature on the subject. It can be concluded that MW heating has solely the thermal effect on gas-solid reactions, and the variations of kinetic parameters are related to the direct and indirect impacts of that. Temperature measurement limitations, physical structure variation, and non-uniform temperature distribution are the primary sources of the discrepa...
RSC Advances
The developed two-step protocol offers a superior reduced graphene oxide TCRGOL quality (7 layers... more The developed two-step protocol offers a superior reduced graphene oxide TCRGOL quality (7 layers), and its SET was 94 dB over the X-band.
Journal of Chemical and Petroleum Engineering, 2018
Temperature measurement in microwave systems is essential for thermally driven processes, namely,... more Temperature measurement in microwave systems is essential for thermally driven processes, namely, catalytic reactions and ceramic sintering. Although, the application of direct thermometry methods, namely, thermocouples, have been commonly articulated in the available literature, however, contacted temperature measurement mechanisms have aroused concerns associated with the disruption of the electromagnetic field and local distortion of the field pattern leading to unprecedented measurement uncertainties. Consequently, the application of optical measurement methods has been advocated to diminish the associated concerns. However, due to the economical constrains and measurement range restrictions, the application of optical measurement systems, namely, pyrometers and optical fibers, has been deferred. In this study, an infrared thermopile, a precise and feasible temperature measurement system has been developed and calibrated to perform in microwave irradiation. Furthermore, the accu...
Authors developed a novel pulsation-assisted technic to effectively fluidize the nanoparticles of... more Authors developed a novel pulsation-assisted technic to effectively fluidize the nanoparticles of different types. The developed fluidization technic was primarily investigated inside a transparent tube with 2.5 cm diameter and 20 cm height. A solenoid valve was located in the reactor outlet to switch between ON and OFF positions to intermittently pressurize the gas inside the reactor and then let it exit. Two differential pressure transducers and a high-speed camera recorded the pressure fluctuations of the bed. Superficial gas velocity and intermittence frequency of the solenoid valve were varied to investigate fluidization quality. An experimental procedure was developed to estimate the maximum amount of interparticle forces between the nanoparticles in the bed.
The scarcity of economically-viable crude oil has prompted chemical corporations to look for alte... more The scarcity of economically-viable crude oil has prompted chemical corporations to look for alternative sources of carbon and hydrogen to produce chemicals, biologics and other products. Biomass and waste matter are considered one of the foremost raw materials to develop all of these industries. Canada produces a tremendous amount of waste: 25 million tons (an average of 0.8 ton per capita), of which only 25 % is diverted (Statistics Canada 2008). The remaining 17 million tons per year is either incinerated or landfilled. This volume of waste is seen as an interesting biomass deposit and constitutes an opportunity to source alternative fuels and chemicals. The development and operation of centralized large scale pyrolysis plants to process domestic waste face several problems, which originate mainly from the wide-ranging composition of the feedstock. Also, these installations require a minimum volume of waste to be operational and cost effective, which leads to the costly collection and transportation of waste over long distances. Finally, process scale-up is extremely complex as the operation of large-scale pyrolysis units is subject to serious operational issues. To address these problems, a distributed pyrolysis strategy is proposed, which involves the deployment of small scale reactors at the waste production site for on-site processing. This approach reduces significantly the cost of waste transportation and collection and offers alternative ways of valorizing the biogas, bio-oil, and char. This presentation will discuss the cost benefits of a distributed strategy, the implementation strategy as well as the pyrolysis of common elements found in a garbage bag.
Bioresource Technology, 2015
This work investigates composition and structure of a bio-oil produced form microwave pyrolysis o... more This work investigates composition and structure of a bio-oil produced form microwave pyrolysis of kraft lignin at different conditions. The studied variables were content of microwave-absorber (20-40 wt%) and nominal setting power (1.5-2.7 kW). The measured temperatures after applying the selected conditions for 800 s were 900, 980, 1065, 1150, and 1240 K. The obtained yields of the aqueous phase, oil phase, non-condensable gas, and solid were 17-21%, 15-20%, 21-27%, and 32-40%, respectively. To investigate the extracted chemicals quantitatively and qualitatively, GC-MS and GC-FID were performed on the liquid samples. In addition, 31P and 13C NMR spectroscopy were implemented to provide detailed structure information for the whole oil phase and the raw material. Furthermore, different degradation pathways were suggested to represent the thermal-decomposition of lignin bonds.
Apply of microwave heating in a chemical reaction makes the investigation of reaction kinetics ra... more Apply of microwave heating in a chemical reaction makes the investigation of reaction kinetics rather complex, for the challenges of measuring reaction temperature and reactants' weight during the exposure time. To involve solving these matters, an original bench-scale experimental setup was built. This setup is called microwave thermo-gravimetric-analyzer (MW-TGA), because it works as a traditional thermo-gravimetric-analyzer using microwave heating instead of conventional heating. In addition, MW-TGA is equipped with an innovated thermometer (air-thermometer) that does not suffer from the traditional thermometer drawbacks, particularly when microwave heating is implemented. The efficiency of the air-thermometer was validated using a traditional thermocouple thermometer, an average percentage relative error of ±5% of the reference value was found. Eventually, MW-TGA was employed to examine the kinetics of microwave pyrolysis of sawdust. The estimated kinetic parameters were 54.5 ± 1.5 kJ/mol, 3 ± 0.9 × 105 min−1, and 2 for the reaction activation energy, pre-exponential factor, and reaction order, respectively.
This work presents three kinetic models based on a lumping approach to describe the microwave pyr... more This work presents three kinetic models based on a lumping approach to describe the microwave pyrolysis of kraft lignin. The first model considered the formation of the main pyrolysis products, condensable gas, non-condensable gas, and remaining solid, taking into consideration each as an individual lump. The second model investigated the liquid product while dividing the condensable gas into oil and water products. The oil product contains only chemicals, whereas the water product does not contain any chemicals. In the third model, the oil product was separated into four main groups: (1) phenolics, which contain all of the identified phenolic components using a gas chromatography mass spectrometry (GC MS) analyzer, (2) heavy-molecular-weight components, which contain all of the identified heavy-molecular-weight and undefined components, using GC MS, (3) non-phenolic aromatics with a single ring, and (4) aliphatics. The comparison of the predicted results using the estimated kinetic parameters to the experimental data showed the high capability of the presented models to estimate the product yield under the selected conditions.