Marquidia Pacheco | Instituto Nacional de Investigaciones Nucleares (original) (raw)

Papers by Marquidia Pacheco

Research paper thumbnail of Modeling and Experimental Study on Nitric Oxide Treatment Using Dielectric Barrier Discharge

IEEE Transactions on Plasma Science, Oct 1, 2007

In this paper, nonthermal plasma technology was used to remove nitric oxide (NO) from a mixture o... more In this paper, nonthermal plasma technology was used to remove nitric oxide (NO) from a mixture of air and water vapor. A chemical model was developed to obtain NO removal mechanism and to observe the behavior of the species in the plasma discharge. The influence of water vapor addition on NO removal efficiency was also investigated. Results obtained from the model indicate that the NO removal is mainly achieved by chemical reactions with O • , N • , and OH • radicals. Experimental results of the NO removal process in a dielectric barrier discharge are also presented. Several experimental parameters such as power, frequency, initial concentration of NO, and specific input energy were tested, and a NO x removal efficiency of approximately 98% was achieved. Index Terms-Chemical kinetics, dielectric barrier discharge (DBD), nitric oxide (NO) removal, nonthermal plasma, radicals. I. INTRODUCTION T HE EMISSION of toxic gases has become a main problem around the world; in 2002, the World Health Organization had reported 35 000 premature deaths per year by atmospheric pollution in South America. One of the major anthropogenic gases is nitric oxide (NO) that leads to the formation of acid rain and photochemical smog that damages vegetation and buildings, and contributes to the acidification of rivers, lakes, and other water bodies. Moreover, NO is related to several adverse effects on human health, mainly in heart and lungs. Significant sources of NO x emissions are exhaust gases coming from motor vehicles [1]-[4]. Diverse studies focused on air pollutant removal have demonstrated that nonthermal plasma is an efficient technique for NO x removal [5]-[14]. Nonthermal plasma processes can simultaneously treat several pollutants at atmospheric pressure; furthermore, the initial investment and operation costs are relatively low [15], [16]. Experimental and modeling researches focus on the discharge phenomena and reaction kinetics during Manuscript

Research paper thumbnail of New Data on the Formation of SWNTs by the Electrical Arc Method

Nucleation and Atmospheric Aerosols, 2002

The formation of single-wall carbon nanotubes (SWNTs) and other carbon nanophases by the electric... more The formation of single-wall carbon nanotubes (SWNTs) and other carbon nanophases by the electric arc method was investigated by transmission electron microscopy for various conditions while studying the plasma characteristics (temperature profiles, C 2 concentration) by in-situ emission spectroscopy. Special attention was brought to the anode type, which has not been a thoroughly studied parameter so far. Related parameters were the dispersion of the catalyst (homogeneous or heterogeneous) and the doping with non catalyst phases. Conditions have been found which are able to produce preferentially either SWNTs, or double-wall nanotubes (DWNTs), or single wall nanocapsules (SWNCs). Focussing on the formation of SWNTs, we also determined arc conditions where web production is increased by up to ~230% compared to standard conditions. Impurities are only catalyst remnants and amorphous-or nearly-carbon, suggesting that acidbased purification procedures could be simplified and less severe, with both higher efficiency and lower harmfulness towards SWNT structure. Investigation of the plasma provided interesting results which emphasise the role of the primary structure of the active carbon moieties generated by the anode vaporisation. The unexpected minimisation of the role of C 2 in the SWNT growth mechanism is one of the results.

Research paper thumbnail of Biogas Conversion and Syngas Upgrading Via Warm Plasma Reforming

When Biogas is used as an energy source, hydrogen sulphide and some halogenated compounds can cau... more When Biogas is used as an energy source, hydrogen sulphide and some halogenated compounds can cause some corrosion effects in engines, therefore a conversion in syngas is convenient because it can be used as energy vector, as it is mainly composed by hydrogen and carbon monoxide. Additionally, hydrogen enrichment for other purposes than vehicle fuel is also worthwhile; therefore, upgrading syngas improve the performance of spark ignition engines reducing hydrocarbon emissions.

Research paper thumbnail of Toxic Gas Removal by Dielectric Discharge with Corona Effect

Nucleation and Atmospheric Aerosols, 2006

ABSTRACT In this work, a theoretical and experimental study on SO2 and NOx removal by non‐thermal... more ABSTRACT In this work, a theoretical and experimental study on SO2 and NOx removal by non‐thermal plasma technology, more specifically a dielectric barrier (DBD) discharge combined with the Corona effect, is presented. Results obtained from a theoretical study describe the chemical kinetic model of SO2 and NOx removal processes; the effect of OH radicals in removal of both gases is noteworthy. Experimental results of de‐SO2 process are reported. Also, optical emission spectroscopy study was applied on some atomic helium lines to obtain temperature of electrons in the non‐thermal plasma. © 2006 American Institute of Physics

Research paper thumbnail of Devolatilization of a particle coal in a plasma reactor

Journal of applied research and technology, Nov 4, 2019

Research paper thumbnail of A significant improvement of both yield and purity during SWCNT synthesis via the electric arc process

Carbon, Jul 1, 2007

This paper deals with the optimisation of the single walled carbon nanotube (SWCNT) synthesis by ... more This paper deals with the optimisation of the single walled carbon nanotube (SWCNT) synthesis by the electric arc technique using socalled heterogeneous anodes filled with Ni and Y catalysts along with either graphite (large-grain or small-grain) or diamond powders. The various carbon nanophases produced were analyzed using high-resolution transmission electron microscopy. Plasma physical properties were determined by emission spectroscopy and were correlated to the variation in the carbon products formed. Using large-grain (100 lm) graphite powder corresponded to standard conditions since able to generate impurity-rich SWCNT material resembling that usually described in literature. However, replacing the large-grain graphite powder by small-grain graphite powder ($1 lm) resulted in a dramatic increase in both the yield and purity of the SWCNTs obtained. On the other hand, a similar result was obtained by using diamond powder (grain size $1 lm) instead of the small-grain graphite powder. The results are explained via the erosion modes of the anodes with respect to the apparent density of the powder mixtures filling their cavities. Maintaining a steady plasma composition and a CI/NiI concentration ratio higher than 10 8 are identified as two conditions required for optimising SWCNT synthesis.

Research paper thumbnail of Boron Doped Nanotubes Produced by Thermal Plasma and Their Potential use as Supercapacitor

The supercapacitors currently existing on the market are produced from activated and pyrolyzed wo... more The supercapacitors currently existing on the market are produced from activated and pyrolyzed wood, plants and from oil and phenolic resins (aerogels and cryogels)1. New ways to store energy are being explored, as example, carbon nanostructures due to their high surface area can convert capacitors (low storage capacity with quick charge/discharge) to supercapacitors which combine the advantages of capacitors and batteries (high storage capacity with quick charge/discharge)2, 3.

Research paper thumbnail of Vanadium Redox Flow Battery: Design and Prototype

2022 International Symposium on Electromobility (ISEM)

Research paper thumbnail of Elaboration of a Dielectric Based on Boron Doped Carbon Nanotubes

Research paper thumbnail of Instituto Nacional de Investigaciones Nucleares

Mundo Nano. Revista Interdisciplinaria en Nanociencia y Nanotecnología, 2017

* Se agradece a todos los colaboradores que se desempeñan en el área de NyN, por la información p... more * Se agradece a todos los colaboradores que se desempeñan en el área de NyN, por la información proporcionada para la elaboración de este documento. Investigadores del ININ en NyN:

Research paper thumbnail of Influence of Nickel and Cerium on Carbon Arc and Formation of Carbon Nanostructures

AIP Conference Proceedings, 2003

ABSTRACT Ni- and Ce-doped graphite anodes were DC arced in helium and water to produce 1D nanocar... more ABSTRACT Ni- and Ce-doped graphite anodes were DC arced in helium and water to produce 1D nanocarbons. The products were analyzed by HR SEM and TEM techniques. The synergism of the binary catalysts used has been confirmed. Emission spectroscopy was performed to determine the temperature and C2 radical distributions in the arc.

Research paper thumbnail of Modeling and Experimental Study on Nitric Oxide Treatment Using Dielectric Barrier Discharge

IEEE Transactions on Plasma Science, 2007

In this paper, nonthermal plasma technology was used to remove nitric oxide (NO) from a mixture o... more In this paper, nonthermal plasma technology was used to remove nitric oxide (NO) from a mixture of air and water vapor. A chemical model was developed to obtain NO removal mechanism and to observe the behavior of the species in the plasma discharge. The influence of water vapor addition on NO removal efficiency was also investigated. Results obtained from the model indicate that the NO removal is mainly achieved by chemical reactions with O • , N • , and OH • radicals. Experimental results of the NO removal process in a dielectric barrier discharge are also presented. Several experimental parameters such as power, frequency, initial concentration of NO, and specific input energy were tested, and a NO x removal efficiency of approximately 98% was achieved. Index Terms-Chemical kinetics, dielectric barrier discharge (DBD), nitric oxide (NO) removal, nonthermal plasma, radicals. I. INTRODUCTION T HE EMISSION of toxic gases has become a main problem around the world; in 2002, the World Health Organization had reported 35 000 premature deaths per year by atmospheric pollution in South America. One of the major anthropogenic gases is nitric oxide (NO) that leads to the formation of acid rain and photochemical smog that damages vegetation and buildings, and contributes to the acidification of rivers, lakes, and other water bodies. Moreover, NO is related to several adverse effects on human health, mainly in heart and lungs. Significant sources of NO x emissions are exhaust gases coming from motor vehicles [1]-[4]. Diverse studies focused on air pollutant removal have demonstrated that nonthermal plasma is an efficient technique for NO x removal [5]-[14]. Nonthermal plasma processes can simultaneously treat several pollutants at atmospheric pressure; furthermore, the initial investment and operation costs are relatively low [15], [16]. Experimental and modeling researches focus on the discharge phenomena and reaction kinetics during Manuscript

Research paper thumbnail of Carbon nanofibers synthesis by a glow-electric arc at high frequencies and low power supply

Gas Discharges and …

... A. Juanico 4 and N. Estrada 2 ... A mechanical bomb permits to work in the range of 0.4 to 10... more ... A. Juanico 4 and N. Estrada 2 ... A mechanical bomb permits to work in the range of 0.4 to 100kPa. Two rod electrodes are vertically aligned inside the chamber; the lower electrode contains a catalysts powder containing a mixture of graphite, nickel and yttrium (56%at C-34%at. ...

Research paper thumbnail of Chemical and electrical diagnosis of two configurations of dielectric barrier discharges applied to nitric oxides degradation

How to cite Complete issue More information about this article Journal's homepage in redalyc.org ... more How to cite Complete issue More information about this article Journal's homepage in redalyc.org Scientific Information System Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Non-profit academic project, developed under the open access initiative

Research paper thumbnail of Hydrogel and carbon nanostructures based supercapacitor: Initial steps toward green supercapatteries

Journal of energy storage, Nov 1, 2023

Research paper thumbnail of Warm Plasma Torch for Hydrocarbon Reforming

IEEE Transactions on Plasma Science

This paper treats over a reforming process using a warm plasma reactor for CH4 and CO2 conversion... more This paper treats over a reforming process using a warm plasma reactor for CH4 and CO2 conversion and hydrogen yield recovering. The conversion of hydrocarbon in syngas is mainly contributed by dissociation and ionization processes. Warm plasma is environment-friendly and autosustainable process; in addition, the electric discharge has low specific energy (SE) requirement and is able to retain enough high temperature to produce excited species and support subsequent chemical reactions. Such plasma discharges have significant advantages: do not require extra cooling systems, since they work with reduced electric current and high voltages, decreasing significantly electrode erosion. Consequently, reactors can be accomplished with a simpler framework and high gas treatment capacity. Plasma interaction with greenhouse gases (GHGs) leads into a molecular dissociation, mainly forming CO and H2, also known as syngas. In recent years, the syngas has become one of the alternative energy sources, which is more profitable and investigated. This mixture, normally recovered from organic material decomposition, provides energy with innovative applications in microturbines and fuel cells, in conjunction with other applications. In addition, an experimental analysis by using pulsed or resonant converter power supply is conducted; this converter enables the maximum energy transfer into plasma discharge without requiring complex electronic structures. Electric analysis was performed to determine instantaneous current, voltage, and power applied in the warm plasma torch for GHG treatment. From the analysis of power consumption, flux flow rate, and other physical chemical characteristics, SE and energy conversion efficiency are obtained. The effect of frequency in voltage–current relationship, depending on the waveform source, is described here. The input and exhaust gases were analyzed by a mass spectrometer and a gas analyzer. A comparison of these results with other results obtained in different bibliographic references is also signaled.

Research paper thumbnail of Multilayer Graphene Growth Assisted by Sulfur Using the Arc Discharge Method at Ambient Conditions

IEEE Transactions on Plasma Science

Graphene, a 2-D hexagonal array of carbon atoms, has interesting physical properties, which make ... more Graphene, a 2-D hexagonal array of carbon atoms, has interesting physical properties, which make this material interesting in applications such as energy storage devices and supercapacitors. The approach here proposed is the use of sulfur as a promoter of sp2 bonds to form graphite domains and with the particularity of using air at atmospheric pressure to create an electric arc discharge. From diagnostic realized with Raman spectroscopy, it has been observed that the carbonaceous material obtained without the addition of sulfur has a defective graphitic structure, but when sulfur is added, the formation of multilayer graphene is enhanced. Scanning electronic microscopy corroborates the synthesis of graphene-like material. Optical emission spectroscopy studies were realized to the plasma; electronic and rotational temperatures obtained allow envisaging a local thermodynamic equilibrium; some spectra obtained show the existence of reactive sulfur species which possibly are nucleation centers of graphitic domains.

Research paper thumbnail of Modeling the Voltage Drop Across the Cathode Sheath in HPS

All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.

Research paper thumbnail of Review: Mixed-Matrix Membranes with CNT for CO2 Separation Processes

Membranes

The membranes’ role is of supreme importance in the separation of compounds under different phase... more The membranes’ role is of supreme importance in the separation of compounds under different phases of matter. The topic addressed here is based on the use of membranes on the gases separation, specifically the advantages of mixed-matrix membranes (MMMs) when using carbon nanotubes as fillers to separate carbon dioxide (CO2) from other carrier gas. MMMs consist of a polymer support with additive fillers to improve their efficiency by increasing both selectivity and permeability. The most promising fillers in the MMM development are nanostructured molecules. Due to the good prospects of carbon nanotubes (CNTs) as MMM fillers, this article aims to concentrate the advances and developments of CNT–MMM to separate gases, such as CO2. The influence of functionalized CNT or mixtures of CNT with additional materials such as zeolites, hydrogel and, graphene sheets on membranes performance is highlighted in the present work.

Research paper thumbnail of Greenhouse Gases Reforming and Hydrogen Upgrading by Using Warm Plasma Technology

Green Technologies to Improve the Environment on Earth

Global warming is an alarming problem with adverse impact on climate change. Carbon dioxide (CO 2... more Global warming is an alarming problem with adverse impact on climate change. Carbon dioxide (CO 2) and methane (CH 4) have been identified as the most significant greenhouse gases (GHG) normally arising from anthropogenic activities; therefore, promising treatment technologies are developing all over the world to resolve this problem. The warm plasma is an emergent process with low specific energy requirement capable to reach high temperature to produce excited species and support subsequent chemical reactions. Consequently, warm plasma reactors can be accomplished with simple structure reactors having high gas flow rates and treatment capacity. Plasma interaction with GHG leads into a molecular dissociation, mainly forming CO and H 2 , also known as syngas, which represents an alternative energy source with innovative applications in microturbines and fuel cells, among other emerging applications. The process here explained assures a significant reduction in CO 2 emission and H 2 yield upgrading. The reforming experimental results by using two warm plasma reactors are connected in series to improve the syngas yield. This alternative represents a great possibility for CO 2 conversion.

Research paper thumbnail of Modeling and Experimental Study on Nitric Oxide Treatment Using Dielectric Barrier Discharge

IEEE Transactions on Plasma Science, Oct 1, 2007

In this paper, nonthermal plasma technology was used to remove nitric oxide (NO) from a mixture o... more In this paper, nonthermal plasma technology was used to remove nitric oxide (NO) from a mixture of air and water vapor. A chemical model was developed to obtain NO removal mechanism and to observe the behavior of the species in the plasma discharge. The influence of water vapor addition on NO removal efficiency was also investigated. Results obtained from the model indicate that the NO removal is mainly achieved by chemical reactions with O • , N • , and OH • radicals. Experimental results of the NO removal process in a dielectric barrier discharge are also presented. Several experimental parameters such as power, frequency, initial concentration of NO, and specific input energy were tested, and a NO x removal efficiency of approximately 98% was achieved. Index Terms-Chemical kinetics, dielectric barrier discharge (DBD), nitric oxide (NO) removal, nonthermal plasma, radicals. I. INTRODUCTION T HE EMISSION of toxic gases has become a main problem around the world; in 2002, the World Health Organization had reported 35 000 premature deaths per year by atmospheric pollution in South America. One of the major anthropogenic gases is nitric oxide (NO) that leads to the formation of acid rain and photochemical smog that damages vegetation and buildings, and contributes to the acidification of rivers, lakes, and other water bodies. Moreover, NO is related to several adverse effects on human health, mainly in heart and lungs. Significant sources of NO x emissions are exhaust gases coming from motor vehicles [1]-[4]. Diverse studies focused on air pollutant removal have demonstrated that nonthermal plasma is an efficient technique for NO x removal [5]-[14]. Nonthermal plasma processes can simultaneously treat several pollutants at atmospheric pressure; furthermore, the initial investment and operation costs are relatively low [15], [16]. Experimental and modeling researches focus on the discharge phenomena and reaction kinetics during Manuscript

Research paper thumbnail of New Data on the Formation of SWNTs by the Electrical Arc Method

Nucleation and Atmospheric Aerosols, 2002

The formation of single-wall carbon nanotubes (SWNTs) and other carbon nanophases by the electric... more The formation of single-wall carbon nanotubes (SWNTs) and other carbon nanophases by the electric arc method was investigated by transmission electron microscopy for various conditions while studying the plasma characteristics (temperature profiles, C 2 concentration) by in-situ emission spectroscopy. Special attention was brought to the anode type, which has not been a thoroughly studied parameter so far. Related parameters were the dispersion of the catalyst (homogeneous or heterogeneous) and the doping with non catalyst phases. Conditions have been found which are able to produce preferentially either SWNTs, or double-wall nanotubes (DWNTs), or single wall nanocapsules (SWNCs). Focussing on the formation of SWNTs, we also determined arc conditions where web production is increased by up to ~230% compared to standard conditions. Impurities are only catalyst remnants and amorphous-or nearly-carbon, suggesting that acidbased purification procedures could be simplified and less severe, with both higher efficiency and lower harmfulness towards SWNT structure. Investigation of the plasma provided interesting results which emphasise the role of the primary structure of the active carbon moieties generated by the anode vaporisation. The unexpected minimisation of the role of C 2 in the SWNT growth mechanism is one of the results.

Research paper thumbnail of Biogas Conversion and Syngas Upgrading Via Warm Plasma Reforming

When Biogas is used as an energy source, hydrogen sulphide and some halogenated compounds can cau... more When Biogas is used as an energy source, hydrogen sulphide and some halogenated compounds can cause some corrosion effects in engines, therefore a conversion in syngas is convenient because it can be used as energy vector, as it is mainly composed by hydrogen and carbon monoxide. Additionally, hydrogen enrichment for other purposes than vehicle fuel is also worthwhile; therefore, upgrading syngas improve the performance of spark ignition engines reducing hydrocarbon emissions.

Research paper thumbnail of Toxic Gas Removal by Dielectric Discharge with Corona Effect

Nucleation and Atmospheric Aerosols, 2006

ABSTRACT In this work, a theoretical and experimental study on SO2 and NOx removal by non‐thermal... more ABSTRACT In this work, a theoretical and experimental study on SO2 and NOx removal by non‐thermal plasma technology, more specifically a dielectric barrier (DBD) discharge combined with the Corona effect, is presented. Results obtained from a theoretical study describe the chemical kinetic model of SO2 and NOx removal processes; the effect of OH radicals in removal of both gases is noteworthy. Experimental results of de‐SO2 process are reported. Also, optical emission spectroscopy study was applied on some atomic helium lines to obtain temperature of electrons in the non‐thermal plasma. © 2006 American Institute of Physics

Research paper thumbnail of Devolatilization of a particle coal in a plasma reactor

Journal of applied research and technology, Nov 4, 2019

Research paper thumbnail of A significant improvement of both yield and purity during SWCNT synthesis via the electric arc process

Carbon, Jul 1, 2007

This paper deals with the optimisation of the single walled carbon nanotube (SWCNT) synthesis by ... more This paper deals with the optimisation of the single walled carbon nanotube (SWCNT) synthesis by the electric arc technique using socalled heterogeneous anodes filled with Ni and Y catalysts along with either graphite (large-grain or small-grain) or diamond powders. The various carbon nanophases produced were analyzed using high-resolution transmission electron microscopy. Plasma physical properties were determined by emission spectroscopy and were correlated to the variation in the carbon products formed. Using large-grain (100 lm) graphite powder corresponded to standard conditions since able to generate impurity-rich SWCNT material resembling that usually described in literature. However, replacing the large-grain graphite powder by small-grain graphite powder ($1 lm) resulted in a dramatic increase in both the yield and purity of the SWCNTs obtained. On the other hand, a similar result was obtained by using diamond powder (grain size $1 lm) instead of the small-grain graphite powder. The results are explained via the erosion modes of the anodes with respect to the apparent density of the powder mixtures filling their cavities. Maintaining a steady plasma composition and a CI/NiI concentration ratio higher than 10 8 are identified as two conditions required for optimising SWCNT synthesis.

Research paper thumbnail of Boron Doped Nanotubes Produced by Thermal Plasma and Their Potential use as Supercapacitor

The supercapacitors currently existing on the market are produced from activated and pyrolyzed wo... more The supercapacitors currently existing on the market are produced from activated and pyrolyzed wood, plants and from oil and phenolic resins (aerogels and cryogels)1. New ways to store energy are being explored, as example, carbon nanostructures due to their high surface area can convert capacitors (low storage capacity with quick charge/discharge) to supercapacitors which combine the advantages of capacitors and batteries (high storage capacity with quick charge/discharge)2, 3.

Research paper thumbnail of Vanadium Redox Flow Battery: Design and Prototype

2022 International Symposium on Electromobility (ISEM)

Research paper thumbnail of Elaboration of a Dielectric Based on Boron Doped Carbon Nanotubes

Research paper thumbnail of Instituto Nacional de Investigaciones Nucleares

Mundo Nano. Revista Interdisciplinaria en Nanociencia y Nanotecnología, 2017

* Se agradece a todos los colaboradores que se desempeñan en el área de NyN, por la información p... more * Se agradece a todos los colaboradores que se desempeñan en el área de NyN, por la información proporcionada para la elaboración de este documento. Investigadores del ININ en NyN:

Research paper thumbnail of Influence of Nickel and Cerium on Carbon Arc and Formation of Carbon Nanostructures

AIP Conference Proceedings, 2003

ABSTRACT Ni- and Ce-doped graphite anodes were DC arced in helium and water to produce 1D nanocar... more ABSTRACT Ni- and Ce-doped graphite anodes were DC arced in helium and water to produce 1D nanocarbons. The products were analyzed by HR SEM and TEM techniques. The synergism of the binary catalysts used has been confirmed. Emission spectroscopy was performed to determine the temperature and C2 radical distributions in the arc.

Research paper thumbnail of Modeling and Experimental Study on Nitric Oxide Treatment Using Dielectric Barrier Discharge

IEEE Transactions on Plasma Science, 2007

In this paper, nonthermal plasma technology was used to remove nitric oxide (NO) from a mixture o... more In this paper, nonthermal plasma technology was used to remove nitric oxide (NO) from a mixture of air and water vapor. A chemical model was developed to obtain NO removal mechanism and to observe the behavior of the species in the plasma discharge. The influence of water vapor addition on NO removal efficiency was also investigated. Results obtained from the model indicate that the NO removal is mainly achieved by chemical reactions with O • , N • , and OH • radicals. Experimental results of the NO removal process in a dielectric barrier discharge are also presented. Several experimental parameters such as power, frequency, initial concentration of NO, and specific input energy were tested, and a NO x removal efficiency of approximately 98% was achieved. Index Terms-Chemical kinetics, dielectric barrier discharge (DBD), nitric oxide (NO) removal, nonthermal plasma, radicals. I. INTRODUCTION T HE EMISSION of toxic gases has become a main problem around the world; in 2002, the World Health Organization had reported 35 000 premature deaths per year by atmospheric pollution in South America. One of the major anthropogenic gases is nitric oxide (NO) that leads to the formation of acid rain and photochemical smog that damages vegetation and buildings, and contributes to the acidification of rivers, lakes, and other water bodies. Moreover, NO is related to several adverse effects on human health, mainly in heart and lungs. Significant sources of NO x emissions are exhaust gases coming from motor vehicles [1]-[4]. Diverse studies focused on air pollutant removal have demonstrated that nonthermal plasma is an efficient technique for NO x removal [5]-[14]. Nonthermal plasma processes can simultaneously treat several pollutants at atmospheric pressure; furthermore, the initial investment and operation costs are relatively low [15], [16]. Experimental and modeling researches focus on the discharge phenomena and reaction kinetics during Manuscript

Research paper thumbnail of Carbon nanofibers synthesis by a glow-electric arc at high frequencies and low power supply

Gas Discharges and …

... A. Juanico 4 and N. Estrada 2 ... A mechanical bomb permits to work in the range of 0.4 to 10... more ... A. Juanico 4 and N. Estrada 2 ... A mechanical bomb permits to work in the range of 0.4 to 100kPa. Two rod electrodes are vertically aligned inside the chamber; the lower electrode contains a catalysts powder containing a mixture of graphite, nickel and yttrium (56%at C-34%at. ...

Research paper thumbnail of Chemical and electrical diagnosis of two configurations of dielectric barrier discharges applied to nitric oxides degradation

How to cite Complete issue More information about this article Journal's homepage in redalyc.org ... more How to cite Complete issue More information about this article Journal's homepage in redalyc.org Scientific Information System Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Non-profit academic project, developed under the open access initiative

Research paper thumbnail of Hydrogel and carbon nanostructures based supercapacitor: Initial steps toward green supercapatteries

Journal of energy storage, Nov 1, 2023

Research paper thumbnail of Warm Plasma Torch for Hydrocarbon Reforming

IEEE Transactions on Plasma Science

This paper treats over a reforming process using a warm plasma reactor for CH4 and CO2 conversion... more This paper treats over a reforming process using a warm plasma reactor for CH4 and CO2 conversion and hydrogen yield recovering. The conversion of hydrocarbon in syngas is mainly contributed by dissociation and ionization processes. Warm plasma is environment-friendly and autosustainable process; in addition, the electric discharge has low specific energy (SE) requirement and is able to retain enough high temperature to produce excited species and support subsequent chemical reactions. Such plasma discharges have significant advantages: do not require extra cooling systems, since they work with reduced electric current and high voltages, decreasing significantly electrode erosion. Consequently, reactors can be accomplished with a simpler framework and high gas treatment capacity. Plasma interaction with greenhouse gases (GHGs) leads into a molecular dissociation, mainly forming CO and H2, also known as syngas. In recent years, the syngas has become one of the alternative energy sources, which is more profitable and investigated. This mixture, normally recovered from organic material decomposition, provides energy with innovative applications in microturbines and fuel cells, in conjunction with other applications. In addition, an experimental analysis by using pulsed or resonant converter power supply is conducted; this converter enables the maximum energy transfer into plasma discharge without requiring complex electronic structures. Electric analysis was performed to determine instantaneous current, voltage, and power applied in the warm plasma torch for GHG treatment. From the analysis of power consumption, flux flow rate, and other physical chemical characteristics, SE and energy conversion efficiency are obtained. The effect of frequency in voltage–current relationship, depending on the waveform source, is described here. The input and exhaust gases were analyzed by a mass spectrometer and a gas analyzer. A comparison of these results with other results obtained in different bibliographic references is also signaled.

Research paper thumbnail of Multilayer Graphene Growth Assisted by Sulfur Using the Arc Discharge Method at Ambient Conditions

IEEE Transactions on Plasma Science

Graphene, a 2-D hexagonal array of carbon atoms, has interesting physical properties, which make ... more Graphene, a 2-D hexagonal array of carbon atoms, has interesting physical properties, which make this material interesting in applications such as energy storage devices and supercapacitors. The approach here proposed is the use of sulfur as a promoter of sp2 bonds to form graphite domains and with the particularity of using air at atmospheric pressure to create an electric arc discharge. From diagnostic realized with Raman spectroscopy, it has been observed that the carbonaceous material obtained without the addition of sulfur has a defective graphitic structure, but when sulfur is added, the formation of multilayer graphene is enhanced. Scanning electronic microscopy corroborates the synthesis of graphene-like material. Optical emission spectroscopy studies were realized to the plasma; electronic and rotational temperatures obtained allow envisaging a local thermodynamic equilibrium; some spectra obtained show the existence of reactive sulfur species which possibly are nucleation centers of graphitic domains.

Research paper thumbnail of Modeling the Voltage Drop Across the Cathode Sheath in HPS

All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.

Research paper thumbnail of Review: Mixed-Matrix Membranes with CNT for CO2 Separation Processes

Membranes

The membranes’ role is of supreme importance in the separation of compounds under different phase... more The membranes’ role is of supreme importance in the separation of compounds under different phases of matter. The topic addressed here is based on the use of membranes on the gases separation, specifically the advantages of mixed-matrix membranes (MMMs) when using carbon nanotubes as fillers to separate carbon dioxide (CO2) from other carrier gas. MMMs consist of a polymer support with additive fillers to improve their efficiency by increasing both selectivity and permeability. The most promising fillers in the MMM development are nanostructured molecules. Due to the good prospects of carbon nanotubes (CNTs) as MMM fillers, this article aims to concentrate the advances and developments of CNT–MMM to separate gases, such as CO2. The influence of functionalized CNT or mixtures of CNT with additional materials such as zeolites, hydrogel and, graphene sheets on membranes performance is highlighted in the present work.

Research paper thumbnail of Greenhouse Gases Reforming and Hydrogen Upgrading by Using Warm Plasma Technology

Green Technologies to Improve the Environment on Earth

Global warming is an alarming problem with adverse impact on climate change. Carbon dioxide (CO 2... more Global warming is an alarming problem with adverse impact on climate change. Carbon dioxide (CO 2) and methane (CH 4) have been identified as the most significant greenhouse gases (GHG) normally arising from anthropogenic activities; therefore, promising treatment technologies are developing all over the world to resolve this problem. The warm plasma is an emergent process with low specific energy requirement capable to reach high temperature to produce excited species and support subsequent chemical reactions. Consequently, warm plasma reactors can be accomplished with simple structure reactors having high gas flow rates and treatment capacity. Plasma interaction with GHG leads into a molecular dissociation, mainly forming CO and H 2 , also known as syngas, which represents an alternative energy source with innovative applications in microturbines and fuel cells, among other emerging applications. The process here explained assures a significant reduction in CO 2 emission and H 2 yield upgrading. The reforming experimental results by using two warm plasma reactors are connected in series to improve the syngas yield. This alternative represents a great possibility for CO 2 conversion.