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ABOUT ME
Currently at Universidad de Las Américas, Ecuador
http://investigacion.udla.edu.ec/udla_teams/katiuska-alexandrino/
PUBLICATIONS
2018
Alexandrino, Katiuska; Millera, Ángela; Bilbao, Rafael; Alzueta, María U
Gas and soot formed in the dimethoxymethane pyrolysis. Soot characterization Journal Article
In: Fuel Processing Technology, vol. 179, pp. 369–377, 2018, ISSN: 03783820.
@article{Alexandrino2018a,
title = {Gas and soot formed in the dimethoxymethane pyrolysis. Soot characterization},
author = {Katiuska Alexandrino and Ángela Millera and Rafael Bilbao and María U Alzueta},
doi = {10.1016/j.fuproc.2018.07.021},
issn = {03783820},
year = {2018},
date = {2018-10-01},
journal = {Fuel Processing Technology},
volume = {179},
pages = {369--377},
publisher = {Elsevier B.V.},
abstract = {The many simultaneous processes occurring within in a diesel engine make difficult a thorough understanding of the mechanisms responsible for reduction of soot and/or NOX when an oxygenated compound is added to diesel fuel. Thus, in order to explore the use of oxygenated compounds as biofuels/additives, it is interesting to study their conversion under well-controlled laboratory conditions, together with kinetic studies that help to interpret and understand the reaction schemes that occur during such processes. The aim of this work has been to contribute to the knowledge of the dimethoxymethane (DMM) pyrolysis, one of the oxygenated compounds proposed in literature as alternative fuel. In this way, the influence of pyrolysis temperature (1075–1475 K) and inlet fuel concentration (33,333 and 50,000 ppm DMM) on the sooting propensity of DMM, soot reactivity and its properties is analyzed. Therefore, this work includes pyrolysis experiments under different experimental conditions, focusing on the gas-phase analysis and the soot formation, together with a gas-phase model. Additionally, the interaction of soot with O2 and with NO has been studied, and since soot properties are important on the oxidation rate, selected soot samples have been characterized by different instrumental techniques (elemental analysis, physical adsorption with N2, Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), and Raman spectroscopy).},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The many simultaneous processes occurring within in a diesel engine make difficult a thorough understanding of the mechanisms responsible for reduction of soot and/or NOX when an oxygenated compound is added to diesel fuel. Thus, in order to explore the use of oxygenated compounds as biofuels/additives, it is interesting to study their conversion under well-controlled laboratory conditions, together with kinetic studies that help to interpret and understand the reaction schemes that occur during such processes. The aim of this work has been to contribute to the knowledge of the dimethoxymethane (DMM) pyrolysis, one of the oxygenated compounds proposed in literature as alternative fuel. In this way, the influence of pyrolysis temperature (1075–1475 K) and inlet fuel concentration (33,333 and 50,000 ppm DMM) on the sooting propensity of DMM, soot reactivity and its properties is analyzed. Therefore, this work includes pyrolysis experiments under different experimental conditions, focusing on the gas-phase analysis and the soot formation, together with a gas-phase model. Additionally, the interaction of soot with O2 and with NO has been studied, and since soot properties are important on the oxidation rate, selected soot samples have been characterized by different instrumental techniques (elemental analysis, physical adsorption with N2, Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), and Raman spectroscopy).
Alexandrino, Katiuska; Alzueta, María U; Curran, Henry J
An experimental and modeling study of the ignition of dimethyl carbonate in shock tubes and rapid compression machine Journal Article
In: Combustion and Flame, vol. 188, pp. 212–226, 2018, ISSN: 15562921.
@article{Alexandrino2018,
title = {An experimental and modeling study of the ignition of dimethyl carbonate in shock tubes and rapid compression machine},
author = {Katiuska Alexandrino and María U Alzueta and Henry J Curran},
doi = {10.1016/j.combustflame.2017.10.001},
issn = {15562921},
year = {2018},
date = {2018-02-01},
journal = {Combustion and Flame},
volume = {188},
pages = {212--226},
publisher = {Elsevier Inc.},
abstract = {Ignition delay times of dimethyl carbonate DMC were measured using low- and high-pressure shock tubes and in a rapid compression machine (RCM). In this way, the effect of fuel concentration (0.75% and 1.75%), pressure (2.0, 20, and 40 atm) and equivalence ratio (0.5, 1.0, 2.0) on ignition delay times was studied experimentally and computationally using a chemical kinetic model. Experiments cover the temperature range of 795–1585 K. Several models from the literature were used to perform simulations, thus their performances to predict the present experimental data was examined. Furthermore, the effect of the thermodynamic data of the CH3O(C[dbnd]O)Ȯ radical species and the fuel consumption reaction CH3O(C[dbnd]O)OCH3 ⇄ CH3O(C[dbnd]O)Ȯ + ĊH3, on the simulations of the ignition delay times of DMC was analyzed using the different models. Reaction path and sensitivity analyses were carried out with a final recommended model to present an in-depth analysis of the oxidation of DMC under the different conditions studied. The final model uses AramcoMech 2.0 as the base mechanism and includes a DMC sub-mechanism available in the literature in which the reaction CH3O(C[dbnd]O)OCH3 ⇄ CH3O(C[dbnd]O)Ȯ + ĊH3has been modified. Good agreement is observed between calculated and experimental data. The model was also validated using available experimental data from flow reactors and opposed flow diffusion and laminar premixed flame studies showing an overall good performance.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Ignition delay times of dimethyl carbonate DMC were measured using low- and high-pressure shock tubes and in a rapid compression machine (RCM). In this way, the effect of fuel concentration (0.75% and 1.75%), pressure (2.0, 20, and 40 atm) and equivalence ratio (0.5, 1.0, 2.0) on ignition delay times was studied experimentally and computationally using a chemical kinetic model. Experiments cover the temperature range of 795–1585 K. Several models from the literature were used to perform simulations, thus their performances to predict the present experimental data was examined. Furthermore, the effect of the thermodynamic data of the CH3O(C[dbnd]O)Ȯ radical species and the fuel consumption reaction CH3O(C[dbnd]O)OCH3 ⇄ CH3O(C[dbnd]O)Ȯ + ĊH3, on the simulations of the ignition delay times of DMC was analyzed using the different models. Reaction path and sensitivity analyses were carried out with a final recommended model to present an in-depth analysis of the oxidation of DMC under the different conditions studied. The final model uses AramcoMech 2.0 as the base mechanism and includes a DMC sub-mechanism available in the literature in which the reaction CH3O(C[dbnd]O)OCH3 ⇄ CH3O(C[dbnd]O)Ȯ + ĊH3has been modified. Good agreement is observed between calculated and experimental data. The model was also validated using available experimental data from flow reactors and opposed flow diffusion and laminar premixed flame studies showing an overall good performance.
Alexandrino, Katiuska; Baena, Cristian; Millera, Ángela; Bilbao, Rafael; Alzueta, María U
2-methylfuran pyrolysis: Gas-phase modelling and soot formation Journal Article
In: Combustion and Flame, vol. 188, pp. 376–387, 2018, ISSN: 15562921.
@article{Alexandrino2018b,
title = {2-methylfuran pyrolysis: Gas-phase modelling and soot formation},
author = {Katiuska Alexandrino and Cristian Baena and Ángela Millera and Rafael Bilbao and María U Alzueta},
doi = {10.1016/j.combustflame.2017.10.017},
issn = {15562921},
year = {2018},
date = {2018-02-01},
journal = {Combustion and Flame},
volume = {188},
pages = {376--387},
publisher = {Elsevier Inc.},
abstract = {Since the recent discoveries in the high efficiency production methods of 2,5-dimethylfuran (2,5-DMF) and 2-methylfuran (2-MF), and due to their good physicochemical properties, these alkylated furan derivatives have been highly considered as fuels or additives in gasoline and diesel engines. However, the cyclic structures of 2,5-DMF and 2-MF may make them effective soot precursors. We have recently studied the capacity of 2,5-DMF to form soot under different pyrolysis experimental conditions, in a flow reactor, and we now focus on the study of the capacity of 2-MF to form soot under the same conditions. In this way, a systematic investigation of the temperature and fuel concentration effects on the soot formed in the 2-MF pyrolysis was undertaken, in an atmospheric-pressure flow reactor, in the temperature range of 975–1475 K, and with 9000 and 18,000 ppm of 2-MF (inlet total carbon of 45,000 and 90,000 ppm, respectively). The increase in the soot yield is favoured by the rise in both the temperature and the inlet 2-MF concentration, while the gas yield decreases as the temperature increases without a noticeable influence of the inlet 2-MF concentration. A gas-phase chemical kinetic model was proposed to describe both the pyrolysis of 2-MF and 2,5-DMF. It was validated against the gas-phase data obtained in this work, as well as with a series of experimental data from literature including shock tube and flow reactors. Results show that 2-MF has a high capacity to form soot, and C4 species play a major role in the formation of intermediates that yield polycyclic aromatic hydrocarbons (PAH), well known as soot precursors. However, the soot yield in the 2-MF pyrolysis was found to be lower than that in the 2,5-DMF pyrolysis, mainly because, according to modelling results, during the 2,5-DMF pyrolysis the cyclopentadienyl radicals are highly formed, whose recombination yields directly naphthalene without any other intermediate.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Since the recent discoveries in the high efficiency production methods of 2,5-dimethylfuran (2,5-DMF) and 2-methylfuran (2-MF), and due to their good physicochemical properties, these alkylated furan derivatives have been highly considered as fuels or additives in gasoline and diesel engines. However, the cyclic structures of 2,5-DMF and 2-MF may make them effective soot precursors. We have recently studied the capacity of 2,5-DMF to form soot under different pyrolysis experimental conditions, in a flow reactor, and we now focus on the study of the capacity of 2-MF to form soot under the same conditions. In this way, a systematic investigation of the temperature and fuel concentration effects on the soot formed in the 2-MF pyrolysis was undertaken, in an atmospheric-pressure flow reactor, in the temperature range of 975–1475 K, and with 9000 and 18,000 ppm of 2-MF (inlet total carbon of 45,000 and 90,000 ppm, respectively). The increase in the soot yield is favoured by the rise in both the temperature and the inlet 2-MF concentration, while the gas yield decreases as the temperature increases without a noticeable influence of the inlet 2-MF concentration. A gas-phase chemical kinetic model was proposed to describe both the pyrolysis of 2-MF and 2,5-DMF. It was validated against the gas-phase data obtained in this work, as well as with a series of experimental data from literature including shock tube and flow reactors. Results show that 2-MF has a high capacity to form soot, and C4 species play a major role in the formation of intermediates that yield polycyclic aromatic hydrocarbons (PAH), well known as soot precursors. However, the soot yield in the 2-MF pyrolysis was found to be lower than that in the 2,5-DMF pyrolysis, mainly because, according to modelling results, during the 2,5-DMF pyrolysis the cyclopentadienyl radicals are highly formed, whose recombination yields directly naphthalene without any other intermediate.
2016
Alexandrino, Katiuska; Salinas, Juan; Millera, Ángela; Bilbao, Rafael; Alzueta, María U
Sooting propensity of dimethyl carbonate, soot reactivity and characterization Journal Article
In: Fuel, vol. 183, pp. 64–72, 2016, ISSN: 00162361.
@article{Alexandrino2016c,
title = {Sooting propensity of dimethyl carbonate, soot reactivity and characterization},
author = {Katiuska Alexandrino and Juan Salinas and Ángela Millera and Rafael Bilbao and María U Alzueta},
doi = {10.1016/j.fuel.2016.06.058},
issn = {00162361},
year = {2016},
date = {2016-11-01},
journal = {Fuel},
volume = {183},
pages = {64--72},
publisher = {Elsevier Ltd},
abstract = {Oxygenated compounds have gained interest in the last few years because they represent an attractive alternative as additive to diesel fuel for reducing soot emissions. Although dimethyl carbonate (DMC) seems to be a good option, studies about its propensity to form soot, as well as the knowledge of the characteristics of this soot are still missing. For that reason, this paper focuses on the potential of DMC to form soot, as well as on the reactivity and characterization of this soot. Results from pyrolysis experiments performed in an atmospheric pressure flow reactor at different temperatures (1075-1475 K) and inlet DMC concentrations (approximately 33,333 and 50,000 ppm) show that both soot and gas yields are affected by the pyrolysis temperature, while an increase in the inlet DMC concentration only affects slightly the soot yield, without notable influence on the gas yield. DMC shows a very low tendency to produce soot because the CO/CO2 formation is favoured and thus few carbon atoms are available for soot formation. A chemical kinetic model developed, without incorporating soot particles dynamics, can predict well the gas-phase trends. The comparison of the soot amount profile obtained with the PAH amount profile determined by the model suggests a good first approach toward a model including soot formation. The soot reactivity study toward O2 (500 ppm) and NO (2000 ppm) at 1475 K, as well as its characterization, show that the higher the temperature and the inlet DMC concentration of soot formation, the lower the reactivity of the soot.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Oxygenated compounds have gained interest in the last few years because they represent an attractive alternative as additive to diesel fuel for reducing soot emissions. Although dimethyl carbonate (DMC) seems to be a good option, studies about its propensity to form soot, as well as the knowledge of the characteristics of this soot are still missing. For that reason, this paper focuses on the potential of DMC to form soot, as well as on the reactivity and characterization of this soot. Results from pyrolysis experiments performed in an atmospheric pressure flow reactor at different temperatures (1075-1475 K) and inlet DMC concentrations (approximately 33,333 and 50,000 ppm) show that both soot and gas yields are affected by the pyrolysis temperature, while an increase in the inlet DMC concentration only affects slightly the soot yield, without notable influence on the gas yield. DMC shows a very low tendency to produce soot because the CO/CO2 formation is favoured and thus few carbon atoms are available for soot formation. A chemical kinetic model developed, without incorporating soot particles dynamics, can predict well the gas-phase trends. The comparison of the soot amount profile obtained with the PAH amount profile determined by the model suggests a good first approach toward a model including soot formation. The soot reactivity study toward O2 (500 ppm) and NO (2000 ppm) at 1475 K, as well as its characterization, show that the higher the temperature and the inlet DMC concentration of soot formation, the lower the reactivity of the soot.
Alexandrino, Katiuska; Salvo, Pablo; Millera, Ángela; Bilbao, Rafael; Alzueta, María U
Influence of the Temperature and 2,5-Dimethylfuran Concentration on Its Sooting Tendency Journal Article
In: Combustion Science and Technology, vol. 188, no. 4-5, pp. 651–666, 2016, ISSN: 1563521X.
@article{Alexandrino2016a,
title = {Influence of the Temperature and 2,5-Dimethylfuran Concentration on Its Sooting Tendency},
author = {Katiuska Alexandrino and Pablo Salvo and Ángela Millera and Rafael Bilbao and María U Alzueta},
url = {https://www.tandfonline.com/doi/abs/10.1080/00102202.2016.1138828},
doi = {10.1080/00102202.2016.1138828},
issn = {1563521X},
year = {2016},
date = {2016-05-01},
journal = {Combustion Science and Technology},
volume = {188},
number = {4-5},
pages = {651--666},
publisher = {Taylor and Francis Inc.},
abstract = {The sooting tendency of 2,5-dimethylfuran (2,5-DMF), as a proposed fuel or fuel additive, has been studied in a flow reactor at different reaction temperatures (975, 1075, 1175, 1275, 1375, and 1475 K) and inlet 2,5-DMF concentrations (5000, 7500, and 15,000 ppm) under pyrolytic conditions. The quantification of soot and light gases has been done. Additionally, the experimental results of the light gases have been simulated with a detailed gas-phase chemical kinetic model. The experimental results indicate that the temperature has a great influence on both the soot and gas yields, as well as on the concentration of the light gases of pyrolysis. The inlet 2,5-DMF concentration influences the soot yield, whereas no significant effect is observed on the gas yield.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The sooting tendency of 2,5-dimethylfuran (2,5-DMF), as a proposed fuel or fuel additive, has been studied in a flow reactor at different reaction temperatures (975, 1075, 1175, 1275, 1375, and 1475 K) and inlet 2,5-DMF concentrations (5000, 7500, and 15,000 ppm) under pyrolytic conditions. The quantification of soot and light gases has been done. Additionally, the experimental results of the light gases have been simulated with a detailed gas-phase chemical kinetic model. The experimental results indicate that the temperature has a great influence on both the soot and gas yields, as well as on the concentration of the light gases of pyrolysis. The inlet 2,5-DMF concentration influences the soot yield, whereas no significant effect is observed on the gas yield.