The Experts below are selected from a list of 6612 Experts worldwide ranked by ideXlab platform

Jennifer Wilcox - One of the best experts on this subject based on the ideXlab platform.

  • prospects of co2 capture via 13x for low carbon hydrogen production using a pd based Metallic Membrane reactor
    Chemical Engineering Journal, 2021
    Co-Authors: Kourosh Kian, Simona Liguori, Helene Pilorge, James M Crawford, Moises A Carreon, Julia L Martin, Ronald L Grimm, Jennifer Wilcox
    Abstract:

    Abstract In this work steam methane reforming (SMR) was carried in a palladium-based Membrane reactor and its performance was evaluated in terms of methane conversion, hydrogen recovery, hydrogen purity, and CO and CO2 selectivity. The Membrane reactor was found to produce ultrahigh purity hydrogen with methane conversions as high as 40% at moderate operating conditions and in the absence of sweep gas. Permeation tests using pure hydrogen and inert gases indicate that the Membrane reactor is highly selective toward hydrogen. The SMR reactions were performed at 673 K and operating pressures ranging from 100 to 400 kPa. A gas hourly space velocity of 2,600 hr-1 and a steam-to-carbon ratio of 3.5 were used. Methane conversion increased from approximately 23% at 100 kPa to 42% at 400 kPa while a maximum hydrogen recovery value of 43% was achieved at 400 kPa. Furthermore, the purity of the recovered hydrogen was >99.999%. The carbon capture experiments performed in this work consist of dehydrating the retentate stream and redirecting it to a zeolite 13X packed bed before analyzing the stream via mass spectrometry. The carbon capture studies reveal that approximately 5.96 mmol CO2 (262.25 mg of CO2) can be captured per gram of 13X. This value indicates that approximately 80% of the produced CO2 via the SMR, can be captured before the sorbent bed is completely saturated. SEM-EDS, XRD, and XPS techniques were used to characterize the crystal structure and morphology of the Membrane surface. These studies reveal that the surface of the Membrane underwent significant oxidation during the SMR reaction. This oxidation is only limited to a few nanometers within the top surface of the palladium.

  • opportunities and challenges of low carbon hydrogen via Metallic Membranes
    Progress in Energy and Combustion Science, 2020
    Co-Authors: Simona Liguori, Kourosh Kian, Nora C Buggy, Bryce H Anzelmo, Jennifer Wilcox
    Abstract:

    Abstract Today, electricity & heat generation, transportation, and industrial sectors together produce more than 80% of energy-related CO2 emissions. Hydrogen may be used as an energy carrier and an alternative fuel in the industrial, residential, and transportation sectors for either heating, energy production from fuel cells, or direct fueling of vehicles. In particular, the use of hydrogen fuel cell vehicles (HFCVs) has the potential to virtually eliminate CO2 emissions from tailpipes and considerably reduce overall emissions from the transportation sector. Although steam methane reforming (SMR) is the dominant industrial process for hydrogen production, environmental concerns associated with CO2 emissions along with the process intensification and energy optimization are areas that still require improvement. Metallic Membrane reactors (MRs) have the potential to address both challenges. MRs operate at significantly lower pressures and temperatures compared with the conventional reactors. Hence, the capital and operating expenses could be considerably lower compared with the conventional reactors. Moreover, Metallic Membranes, specifically Pd and its alloys, inherently allow for only hydrogen permeation, making it possible to produce a stream of up to 99.999+% purity. For smaller and emerging hydrogen markets such as the semiconductor and fuel cell industries, Pd-based Membranes may be an appropriate technology based on the scales and purity requirements. In particular, at lower hydrogen production rates in small-scale plants, MRs with CCUS could be competitive compared to centralized H2 production. On-site hydrogen production would also provide a self-sufficient supply and further circumvent delivery delays as well as issues with storage safety. In addition, hydrogen-producing MRs are a potential avenue to alleviate carbon emissions. However, material availability, Pd cost, and scale-up potential on the order of 1.5 million m3/day may be limiting factors preventing wider application of Pd-based Membranes. Regarding the economic production of hydrogen, the benchmark by the year 2020 has been determined and set in place by the U.S. DOE at less than $2.00 per kg of produced hydrogen. While the established SMR process can easily meet the set limit by DOE, other carbon-free processes such as water electrolysis, electron beam radiolysis, and gliding arc technologies do not presently meet this requirement. In particular, it is expected that the cost of hydrogen produced from natural gas without CCUS will remain the lowest among all of the technologies, while the hydrogen cost produced from an SMR plant with solvent-based carbon capture could be twice as expensive as the conventional SMR without carbon capture. Pd-based MRs have the potential to produce hydrogen at competitive prices with SMR plants equipped with carbon capture. Despite the significant improvements in the electrolysis technologies, the cost of hydrogen produced by electrolysis may remain significantly higher in most geographical locations compared with the hydrogen produced from fossil fuels. The cost of hydrogen via electrolysis may vary up to a factor of ten,d epending on the location and the electricity source. Nevertheless, due to its modular nature, the electrolysis process will likely play a significant role in the hydrogen economy when implemented in suitable geographical locations and powered by renewable electricity. This review provides a critical overview of the opportunities and challenges associated with the use of the MRs to produce high-purity hydrogen with low carbon emissions. Moreover, a technoeconomic review of the potential methods for hydrogen production is provided and the drawbacks and advantages of each method are presented and discussed.

Simona Liguori - One of the best experts on this subject based on the ideXlab platform.

  • prospects of co2 capture via 13x for low carbon hydrogen production using a pd based Metallic Membrane reactor
    Chemical Engineering Journal, 2021
    Co-Authors: Kourosh Kian, Simona Liguori, Helene Pilorge, James M Crawford, Moises A Carreon, Julia L Martin, Ronald L Grimm, Jennifer Wilcox
    Abstract:

    Abstract In this work steam methane reforming (SMR) was carried in a palladium-based Membrane reactor and its performance was evaluated in terms of methane conversion, hydrogen recovery, hydrogen purity, and CO and CO2 selectivity. The Membrane reactor was found to produce ultrahigh purity hydrogen with methane conversions as high as 40% at moderate operating conditions and in the absence of sweep gas. Permeation tests using pure hydrogen and inert gases indicate that the Membrane reactor is highly selective toward hydrogen. The SMR reactions were performed at 673 K and operating pressures ranging from 100 to 400 kPa. A gas hourly space velocity of 2,600 hr-1 and a steam-to-carbon ratio of 3.5 were used. Methane conversion increased from approximately 23% at 100 kPa to 42% at 400 kPa while a maximum hydrogen recovery value of 43% was achieved at 400 kPa. Furthermore, the purity of the recovered hydrogen was >99.999%. The carbon capture experiments performed in this work consist of dehydrating the retentate stream and redirecting it to a zeolite 13X packed bed before analyzing the stream via mass spectrometry. The carbon capture studies reveal that approximately 5.96 mmol CO2 (262.25 mg of CO2) can be captured per gram of 13X. This value indicates that approximately 80% of the produced CO2 via the SMR, can be captured before the sorbent bed is completely saturated. SEM-EDS, XRD, and XPS techniques were used to characterize the crystal structure and morphology of the Membrane surface. These studies reveal that the surface of the Membrane underwent significant oxidation during the SMR reaction. This oxidation is only limited to a few nanometers within the top surface of the palladium.

  • opportunities and challenges of low carbon hydrogen via Metallic Membranes
    Progress in Energy and Combustion Science, 2020
    Co-Authors: Simona Liguori, Kourosh Kian, Nora C Buggy, Bryce H Anzelmo, Jennifer Wilcox
    Abstract:

    Abstract Today, electricity & heat generation, transportation, and industrial sectors together produce more than 80% of energy-related CO2 emissions. Hydrogen may be used as an energy carrier and an alternative fuel in the industrial, residential, and transportation sectors for either heating, energy production from fuel cells, or direct fueling of vehicles. In particular, the use of hydrogen fuel cell vehicles (HFCVs) has the potential to virtually eliminate CO2 emissions from tailpipes and considerably reduce overall emissions from the transportation sector. Although steam methane reforming (SMR) is the dominant industrial process for hydrogen production, environmental concerns associated with CO2 emissions along with the process intensification and energy optimization are areas that still require improvement. Metallic Membrane reactors (MRs) have the potential to address both challenges. MRs operate at significantly lower pressures and temperatures compared with the conventional reactors. Hence, the capital and operating expenses could be considerably lower compared with the conventional reactors. Moreover, Metallic Membranes, specifically Pd and its alloys, inherently allow for only hydrogen permeation, making it possible to produce a stream of up to 99.999+% purity. For smaller and emerging hydrogen markets such as the semiconductor and fuel cell industries, Pd-based Membranes may be an appropriate technology based on the scales and purity requirements. In particular, at lower hydrogen production rates in small-scale plants, MRs with CCUS could be competitive compared to centralized H2 production. On-site hydrogen production would also provide a self-sufficient supply and further circumvent delivery delays as well as issues with storage safety. In addition, hydrogen-producing MRs are a potential avenue to alleviate carbon emissions. However, material availability, Pd cost, and scale-up potential on the order of 1.5 million m3/day may be limiting factors preventing wider application of Pd-based Membranes. Regarding the economic production of hydrogen, the benchmark by the year 2020 has been determined and set in place by the U.S. DOE at less than $2.00 per kg of produced hydrogen. While the established SMR process can easily meet the set limit by DOE, other carbon-free processes such as water electrolysis, electron beam radiolysis, and gliding arc technologies do not presently meet this requirement. In particular, it is expected that the cost of hydrogen produced from natural gas without CCUS will remain the lowest among all of the technologies, while the hydrogen cost produced from an SMR plant with solvent-based carbon capture could be twice as expensive as the conventional SMR without carbon capture. Pd-based MRs have the potential to produce hydrogen at competitive prices with SMR plants equipped with carbon capture. Despite the significant improvements in the electrolysis technologies, the cost of hydrogen produced by electrolysis may remain significantly higher in most geographical locations compared with the hydrogen produced from fossil fuels. The cost of hydrogen via electrolysis may vary up to a factor of ten,d epending on the location and the electricity source. Nevertheless, due to its modular nature, the electrolysis process will likely play a significant role in the hydrogen economy when implemented in suitable geographical locations and powered by renewable electricity. This review provides a critical overview of the opportunities and challenges associated with the use of the MRs to produce high-purity hydrogen with low carbon emissions. Moreover, a technoeconomic review of the potential methods for hydrogen production is provided and the drawbacks and advantages of each method are presented and discussed.

Giulio C. Sarti - One of the best experts on this subject based on the ideXlab platform.

  • influence of the gas phase resistance on hydrogen flux through thin palladium silver Membranes
    Journal of Membrane Science, 2009
    Co-Authors: Jacopo Catalano, Marco Giacinti Baschetti, Giulio C. Sarti
    Abstract:

    Abstract Pure and mixed gas permeation tests were performed on Pd-based hydrogen selective Membranes at different experimental conditions. In particular the permeance of pure hydrogen as well as of binary and ternary mixtures containing hydrogen, nitrogen and methane was measured, at temperatures ranging from 673 to 773 K and at pressure differences up to 6 bar. The Membranes, supplied by NGK Insulators Ltd., Japan, were formed by a selective Pd–Ag layer (20 wt% Ag) deposited on a tubular ceramic support, and showed very high hydrogen permeance and a practically infinite selectivity toward hydrogen. Interestingly, the permeance values measured in pure gas experiments resulted always higher than those obtained in permeation tests with gas mixtures; in the latter case, moreover, the permeate flux significantly deviates from Sieverts’ law based on the hydrogen partial pressure in the bulk gas phase. Both facts suggest the existence of non-negligible resistances to hydrogen transport in the gas phase itself, in addition to that offered by the Metallic Membrane. Experiments performed with increasing feed flow rates, showed also an increase in hydrogen permeance thus revealing the importance of the concentration polarization effects inside the module. Gas phase mass transport coefficients were calculated and used to determine the role of such a resistance in the overall mass transport process. The Sherwood number was also evaluated and was found to follow a boundary layer type of correlation. A general sensitivity analysis was performed in order to compare the effects on the transMembrane hydrogen flux of the two resistances, with different physical dimensions, offered by the gas phase and the Metallic Membrane. The concentration polarization number thus introduced allows for an a priori identification of the leading resistance at any operating conditions and gives clear indications on the actions required to improve the module performance.

  • Influence of the gas phase resistance on hydrogen flux through thin palladium–silver Membranes
    'Elsevier BV', 2009
    Co-Authors: Jacopo Catalano, Giacinti M. Baschetti, Giulio C. Sarti
    Abstract:

    Pure and mixed gas permeation tests were performed on Pd-based hydrogen selective Membranes at different experimental conditions. In particular the permeance of pure hydrogen as well as of binary and ternary mixtures containing hydrogen, nitrogen and methane was measured at temperatures ranging from 673 to 773 K, and at pressure differences up to 6 bar. The Membranes, supplied by NGK insulator Ltd. Japan, were formed by a selective Pd-Ag layer (20%wt Ag) deposited on a tubular ceramic support, and showed very high hydrogen permeance and a practically infinite selectivity toward hydrogen. Interestingly the permeance values measured in pure gas experiments resulted always higher with respect to those obtained in permeation tests with gas mixtures; in the latter case, moreover, the permeate flux significantly deviates from Sieverts\u2019 law suggesting the existence of non negligible resistances to hydrogen transport in the gas phase, in addition to that offered by the Metallic Membrane. Experiments performed at increased feed flow rates, showed also an increase in hydrogen permeance thus revealing the importance of the concentration polarization effects inside the module. Gas phase mass transport coefficients were calculated and used to determine the role of such a resistance in the overall mass transport process. The Sherwood number was also evaluated and was found to follow a boundary layer type of correlation

Kourosh Kian - One of the best experts on this subject based on the ideXlab platform.

  • prospects of co2 capture via 13x for low carbon hydrogen production using a pd based Metallic Membrane reactor
    Chemical Engineering Journal, 2021
    Co-Authors: Kourosh Kian, Simona Liguori, Helene Pilorge, James M Crawford, Moises A Carreon, Julia L Martin, Ronald L Grimm, Jennifer Wilcox
    Abstract:

    Abstract In this work steam methane reforming (SMR) was carried in a palladium-based Membrane reactor and its performance was evaluated in terms of methane conversion, hydrogen recovery, hydrogen purity, and CO and CO2 selectivity. The Membrane reactor was found to produce ultrahigh purity hydrogen with methane conversions as high as 40% at moderate operating conditions and in the absence of sweep gas. Permeation tests using pure hydrogen and inert gases indicate that the Membrane reactor is highly selective toward hydrogen. The SMR reactions were performed at 673 K and operating pressures ranging from 100 to 400 kPa. A gas hourly space velocity of 2,600 hr-1 and a steam-to-carbon ratio of 3.5 were used. Methane conversion increased from approximately 23% at 100 kPa to 42% at 400 kPa while a maximum hydrogen recovery value of 43% was achieved at 400 kPa. Furthermore, the purity of the recovered hydrogen was >99.999%. The carbon capture experiments performed in this work consist of dehydrating the retentate stream and redirecting it to a zeolite 13X packed bed before analyzing the stream via mass spectrometry. The carbon capture studies reveal that approximately 5.96 mmol CO2 (262.25 mg of CO2) can be captured per gram of 13X. This value indicates that approximately 80% of the produced CO2 via the SMR, can be captured before the sorbent bed is completely saturated. SEM-EDS, XRD, and XPS techniques were used to characterize the crystal structure and morphology of the Membrane surface. These studies reveal that the surface of the Membrane underwent significant oxidation during the SMR reaction. This oxidation is only limited to a few nanometers within the top surface of the palladium.

  • opportunities and challenges of low carbon hydrogen via Metallic Membranes
    Progress in Energy and Combustion Science, 2020
    Co-Authors: Simona Liguori, Kourosh Kian, Nora C Buggy, Bryce H Anzelmo, Jennifer Wilcox
    Abstract:

    Abstract Today, electricity & heat generation, transportation, and industrial sectors together produce more than 80% of energy-related CO2 emissions. Hydrogen may be used as an energy carrier and an alternative fuel in the industrial, residential, and transportation sectors for either heating, energy production from fuel cells, or direct fueling of vehicles. In particular, the use of hydrogen fuel cell vehicles (HFCVs) has the potential to virtually eliminate CO2 emissions from tailpipes and considerably reduce overall emissions from the transportation sector. Although steam methane reforming (SMR) is the dominant industrial process for hydrogen production, environmental concerns associated with CO2 emissions along with the process intensification and energy optimization are areas that still require improvement. Metallic Membrane reactors (MRs) have the potential to address both challenges. MRs operate at significantly lower pressures and temperatures compared with the conventional reactors. Hence, the capital and operating expenses could be considerably lower compared with the conventional reactors. Moreover, Metallic Membranes, specifically Pd and its alloys, inherently allow for only hydrogen permeation, making it possible to produce a stream of up to 99.999+% purity. For smaller and emerging hydrogen markets such as the semiconductor and fuel cell industries, Pd-based Membranes may be an appropriate technology based on the scales and purity requirements. In particular, at lower hydrogen production rates in small-scale plants, MRs with CCUS could be competitive compared to centralized H2 production. On-site hydrogen production would also provide a self-sufficient supply and further circumvent delivery delays as well as issues with storage safety. In addition, hydrogen-producing MRs are a potential avenue to alleviate carbon emissions. However, material availability, Pd cost, and scale-up potential on the order of 1.5 million m3/day may be limiting factors preventing wider application of Pd-based Membranes. Regarding the economic production of hydrogen, the benchmark by the year 2020 has been determined and set in place by the U.S. DOE at less than $2.00 per kg of produced hydrogen. While the established SMR process can easily meet the set limit by DOE, other carbon-free processes such as water electrolysis, electron beam radiolysis, and gliding arc technologies do not presently meet this requirement. In particular, it is expected that the cost of hydrogen produced from natural gas without CCUS will remain the lowest among all of the technologies, while the hydrogen cost produced from an SMR plant with solvent-based carbon capture could be twice as expensive as the conventional SMR without carbon capture. Pd-based MRs have the potential to produce hydrogen at competitive prices with SMR plants equipped with carbon capture. Despite the significant improvements in the electrolysis technologies, the cost of hydrogen produced by electrolysis may remain significantly higher in most geographical locations compared with the hydrogen produced from fossil fuels. The cost of hydrogen via electrolysis may vary up to a factor of ten,d epending on the location and the electricity source. Nevertheless, due to its modular nature, the electrolysis process will likely play a significant role in the hydrogen economy when implemented in suitable geographical locations and powered by renewable electricity. This review provides a critical overview of the opportunities and challenges associated with the use of the MRs to produce high-purity hydrogen with low carbon emissions. Moreover, a technoeconomic review of the potential methods for hydrogen production is provided and the drawbacks and advantages of each method are presented and discussed.

Jacopo Catalano - One of the best experts on this subject based on the ideXlab platform.

  • influence of the gas phase resistance on hydrogen flux through thin palladium silver Membranes
    Journal of Membrane Science, 2009
    Co-Authors: Jacopo Catalano, Marco Giacinti Baschetti, Giulio C. Sarti
    Abstract:

    Abstract Pure and mixed gas permeation tests were performed on Pd-based hydrogen selective Membranes at different experimental conditions. In particular the permeance of pure hydrogen as well as of binary and ternary mixtures containing hydrogen, nitrogen and methane was measured, at temperatures ranging from 673 to 773 K and at pressure differences up to 6 bar. The Membranes, supplied by NGK Insulators Ltd., Japan, were formed by a selective Pd–Ag layer (20 wt% Ag) deposited on a tubular ceramic support, and showed very high hydrogen permeance and a practically infinite selectivity toward hydrogen. Interestingly, the permeance values measured in pure gas experiments resulted always higher than those obtained in permeation tests with gas mixtures; in the latter case, moreover, the permeate flux significantly deviates from Sieverts’ law based on the hydrogen partial pressure in the bulk gas phase. Both facts suggest the existence of non-negligible resistances to hydrogen transport in the gas phase itself, in addition to that offered by the Metallic Membrane. Experiments performed with increasing feed flow rates, showed also an increase in hydrogen permeance thus revealing the importance of the concentration polarization effects inside the module. Gas phase mass transport coefficients were calculated and used to determine the role of such a resistance in the overall mass transport process. The Sherwood number was also evaluated and was found to follow a boundary layer type of correlation. A general sensitivity analysis was performed in order to compare the effects on the transMembrane hydrogen flux of the two resistances, with different physical dimensions, offered by the gas phase and the Metallic Membrane. The concentration polarization number thus introduced allows for an a priori identification of the leading resistance at any operating conditions and gives clear indications on the actions required to improve the module performance.

  • Influence of the gas phase resistance on hydrogen flux through thin palladium–silver Membranes
    'Elsevier BV', 2009
    Co-Authors: Jacopo Catalano, Giacinti M. Baschetti, Giulio C. Sarti
    Abstract:

    Pure and mixed gas permeation tests were performed on Pd-based hydrogen selective Membranes at different experimental conditions. In particular the permeance of pure hydrogen as well as of binary and ternary mixtures containing hydrogen, nitrogen and methane was measured at temperatures ranging from 673 to 773 K, and at pressure differences up to 6 bar. The Membranes, supplied by NGK insulator Ltd. Japan, were formed by a selective Pd-Ag layer (20%wt Ag) deposited on a tubular ceramic support, and showed very high hydrogen permeance and a practically infinite selectivity toward hydrogen. Interestingly the permeance values measured in pure gas experiments resulted always higher with respect to those obtained in permeation tests with gas mixtures; in the latter case, moreover, the permeate flux significantly deviates from Sieverts\u2019 law suggesting the existence of non negligible resistances to hydrogen transport in the gas phase, in addition to that offered by the Metallic Membrane. Experiments performed at increased feed flow rates, showed also an increase in hydrogen permeance thus revealing the importance of the concentration polarization effects inside the module. Gas phase mass transport coefficients were calculated and used to determine the role of such a resistance in the overall mass transport process. The Sherwood number was also evaluated and was found to follow a boundary layer type of correlation