Abstract Fuel cell electric vehicles have recently experienced rising demand. The geographic cove... more Abstract Fuel cell electric vehicles have recently experienced rising demand. The geographic coverage of hydrogen stations, however, is limited. This study proposes an on-site hydrogen production system that converts heavy naphtha to high-purity hydrogen for remote areas without convenient access to hydrogen. It includes a pressurized steam reformer (SR) to produce H2-rich gas and a catalytic membrane reactor (MR) to promote H2-producing reactions and permeate hydrogen. By utilizing the liquid-fuel infrastructure, this compact system can produce hydrogen effectively and make it more accessible. Our paper describes how we maximize the system's hydrogen output by investigating how the operating conditions affect each component. Various tests are performed to select the system's water-gas-shift catalyst (Fe–Cr) and determine the optimal temperatures of the SR (800 °C) and the MR (400 °C). The MR shows enhanced catalytic performance from hydrogen permeation or 1.63 times higher hydrogen output at 25 bar(g) than a reactor that contains only catalyst (no membrane). At this pressure, the MR has a maximum hydrogen output at different SR reformate compositions. The maximization is possible by incorporating Le Chatelier's principle and minimizing methanation. This work is important because it proposes a comprehensive method to maximize on-site hydrogen output and ensure the MR's stable operation.
The CO2 (dry) reforming of hydrocarbons offers an opportunity to convert greenhouse gases into sy... more The CO2 (dry) reforming of hydrocarbons offers an opportunity to convert greenhouse gases into synthesis gas, which can further transform to various valued products. Here we explore the influence of Rh particle size and support on the reforming of propane and methane. To that end, Rh nanoparticles with controlled sizes varying from 1.6‐8.0 nm were synthesized following a polyol reduction method and then dispersed on three different solids: CeZrO2, ZrO2, and CeO2. Catalytic turnover rates along with advanced characterization of fresh and spent catalysts reveal a linear correlation of turnover rates with Rh particle size for both methane and propane reforming. The nature and rate of coke deposition are highly dependent on the support used and its interaction with the metallic phase.
Abstract The propane dehydrogenation assisted by CO2 was investigated by using zirconia and titan... more Abstract The propane dehydrogenation assisted by CO2 was investigated by using zirconia and titania catalysts. The objective of the research was to assist the olefins yield of propylene and ethylene from the dehydrogenation of propane gas. The catalysts were characterized using XRD, SEM, and TPD/TPR. The molar ratios of CO2 of 1.4, 2.6, and 12.2 to propane were used; and the conversion of propane was reduced, while increase of CO2 ratio to propane whereas the propylene selectivity increased. The increase of CO/H2 ratio of reverse water-gas shift reaction was an important for the olefins yield and catalytic stability for 29–203 h without regeneration. The utilization of CO2 showed an increase the propane dehydrogenation to produce propylene to ethylene ratio of 2.8 and a total olefin yield 40–45% over Zr-Ti oxide catalysts was achieved. The study demonstrated the important role of CO2 presence in the propane dehydrogenation.
Fuel feed assembly is higher hydrocarbons and accepts a supply of the liquid fuel feedstock compr... more Fuel feed assembly is higher hydrocarbons and accepts a supply of the liquid fuel feedstock comprising a hydrocarbon and a high molecular weight sulfur-containing compounds having a lower hydrocarbon component and the high hydrocarbon component and a high molecular weight sulfur-containing compound is a volatile lower than the lower hydrocarbon components . A fuel supply assembly supplies the fuel to the fuel cell assembly; Liquid fuel feedstock is at least part of the exposed doemeurosseo liquid fuel feedstock to the gasification conditions is vaporized has a housing unit for the fuel to form a vapor feedstock, containing a liquid fuel feedstock; The gasification conditions is provided by the concentration of the fuel-containing fluid supply high and the concentration of the hydrogen component at lower than the fuel feed steam at high raw material hydrocarbon component and a high molecular weight sulfur compounds to be lower. In addition, the fuel feed assembly, the collection unit is also provided, the fuel supply from the first end to which the raw material vapor to the collection unit for collecting the fuel feed steam from the housing unit so as to be useful in fuel cell assemblies are coupled to the housing unit, the fuel cell assembly has a second end coupled to. Hydrocarbon, steam, vaporization rate, the pre-heater, the reforming pre-heating unit
A method and apparatus for use with an oxidizer assembly of a fuel cell system in which the oxidi... more A method and apparatus for use with an oxidizer assembly of a fuel cell system in which the oxidizer assembly has an oxidizing unit for oxidizing anode exhaust gas containing electrolyte particulates and is adapted or conditioned so as to enable the electrolyte particulates to be removable from the assembly and to be removed from the assembly, and wherein the conditioning and removing occur with the oxidizing unit retained in the oxidizer assembly. The fuel cell system is also adapted so that such conditioning and removing occur with the oxidizing assembly retained in the fuel cell system.
In fuel cells high, and as a pre-treatment assembly and a method for the treatment of a fuel feed... more In fuel cells high, and as a pre-treatment assembly and a method for the treatment of a fuel feedstock containing a hydrocarbon and oxygen have a lower hydrocarbon-containing material, wherein the pre-assembly is de-oxidation bed and fuel feedstock to reduce the oxygen in the fuel feedstock pre-reforming contains a bed, and the deoxygenation bed and said pre-reforming bed is a common reaction vessel to flow through the fuel supply after the raw material is first flowed through a deoxygenation bed, said pre-reforming bed to reduce the higher hydrocarbons containing water and it is arranged in the. The pre-reforming assembly may include propane processing bed for processing propane and propylene in the additional fuel feedstock to, those propane processing bed is arranged in a common reaction vessel with the deoxygenation bed and said pre-reforming bed. Pre-assembly, fuel cell, deoxygenation bed, pre-reforming bed, propane processing bed
An oxidizer catalyst assembly for use in a fuel cell system for oxidizing anode exhaust gas and i... more An oxidizer catalyst assembly for use in a fuel cell system for oxidizing anode exhaust gas and in which a first catalyst member is situated along a gas flow path and a second catalyst member is situated along the gas flow path following the first catalyst member. Each of the catalyst members includes a plurality of channels for passing the gas therethrough and an oxidizing catalyst deposited in the channels. The channel density of the channels of the second catalyst member is greater than the channel density of the channels of the first catalyst member and the channel width of the channels of the second catalyst member is less than the channel width of the channels of the first catalyst member.
Abstract In this paper, we investigated the use of Ni 19.5 -Ru 0.05 /CGO as catalysts for associa... more Abstract In this paper, we investigated the use of Ni 19.5 -Ru 0.05 /CGO as catalysts for associated gas pre-reforming to convert higher hydrocarbon and obtain higher methane content. To increase the content of methane, we perform catalytic pre-reforming experiments at 8 bars. Ni-Ru/CGO fully converted the C 2 –C 5 hydrocarbons at 500 °C. However, the conversion of C2–C5 hydrocarbons decreased from 100% to 80% as the SCR decreased from 3.0 to 1.0. Catalytic degradation occurred at temperatures below 300 °C. Comparing the commercial pre-reforming catalyst (C11PR, produced by Sud-Chemie) with Ni-Ru/CGO catalysts, Ni-Ru/CGO outperformed C11PR under the same conditions. We performed long-term tests with Ni-Ru/CGO. Each long-term test lasted over 900 h. Initially, the methane yield was approximately 60%, and the higher hydrocarbons were fully converted. After 900 h, the methane yield was approximately 55%, and dramatically reaching to 50% at 920 h. Simultaneously, the C 2 –C 5 hydrocarbon yield increased to approximately 8%. After the long-term test, we analyzed the tested catalysts and determined that catalytic degradation occurred due to carbon deposition on the catalyst surface.
Abstract Fuel cell electric vehicles have recently experienced rising demand. The geographic cove... more Abstract Fuel cell electric vehicles have recently experienced rising demand. The geographic coverage of hydrogen stations, however, is limited. This study proposes an on-site hydrogen production system that converts heavy naphtha to high-purity hydrogen for remote areas without convenient access to hydrogen. It includes a pressurized steam reformer (SR) to produce H2-rich gas and a catalytic membrane reactor (MR) to promote H2-producing reactions and permeate hydrogen. By utilizing the liquid-fuel infrastructure, this compact system can produce hydrogen effectively and make it more accessible. Our paper describes how we maximize the system's hydrogen output by investigating how the operating conditions affect each component. Various tests are performed to select the system's water-gas-shift catalyst (Fe–Cr) and determine the optimal temperatures of the SR (800 °C) and the MR (400 °C). The MR shows enhanced catalytic performance from hydrogen permeation or 1.63 times higher hydrogen output at 25 bar(g) than a reactor that contains only catalyst (no membrane). At this pressure, the MR has a maximum hydrogen output at different SR reformate compositions. The maximization is possible by incorporating Le Chatelier's principle and minimizing methanation. This work is important because it proposes a comprehensive method to maximize on-site hydrogen output and ensure the MR's stable operation.
The CO2 (dry) reforming of hydrocarbons offers an opportunity to convert greenhouse gases into sy... more The CO2 (dry) reforming of hydrocarbons offers an opportunity to convert greenhouse gases into synthesis gas, which can further transform to various valued products. Here we explore the influence of Rh particle size and support on the reforming of propane and methane. To that end, Rh nanoparticles with controlled sizes varying from 1.6‐8.0 nm were synthesized following a polyol reduction method and then dispersed on three different solids: CeZrO2, ZrO2, and CeO2. Catalytic turnover rates along with advanced characterization of fresh and spent catalysts reveal a linear correlation of turnover rates with Rh particle size for both methane and propane reforming. The nature and rate of coke deposition are highly dependent on the support used and its interaction with the metallic phase.
Abstract The propane dehydrogenation assisted by CO2 was investigated by using zirconia and titan... more Abstract The propane dehydrogenation assisted by CO2 was investigated by using zirconia and titania catalysts. The objective of the research was to assist the olefins yield of propylene and ethylene from the dehydrogenation of propane gas. The catalysts were characterized using XRD, SEM, and TPD/TPR. The molar ratios of CO2 of 1.4, 2.6, and 12.2 to propane were used; and the conversion of propane was reduced, while increase of CO2 ratio to propane whereas the propylene selectivity increased. The increase of CO/H2 ratio of reverse water-gas shift reaction was an important for the olefins yield and catalytic stability for 29–203 h without regeneration. The utilization of CO2 showed an increase the propane dehydrogenation to produce propylene to ethylene ratio of 2.8 and a total olefin yield 40–45% over Zr-Ti oxide catalysts was achieved. The study demonstrated the important role of CO2 presence in the propane dehydrogenation.
Fuel feed assembly is higher hydrocarbons and accepts a supply of the liquid fuel feedstock compr... more Fuel feed assembly is higher hydrocarbons and accepts a supply of the liquid fuel feedstock comprising a hydrocarbon and a high molecular weight sulfur-containing compounds having a lower hydrocarbon component and the high hydrocarbon component and a high molecular weight sulfur-containing compound is a volatile lower than the lower hydrocarbon components . A fuel supply assembly supplies the fuel to the fuel cell assembly; Liquid fuel feedstock is at least part of the exposed doemeurosseo liquid fuel feedstock to the gasification conditions is vaporized has a housing unit for the fuel to form a vapor feedstock, containing a liquid fuel feedstock; The gasification conditions is provided by the concentration of the fuel-containing fluid supply high and the concentration of the hydrogen component at lower than the fuel feed steam at high raw material hydrocarbon component and a high molecular weight sulfur compounds to be lower. In addition, the fuel feed assembly, the collection unit is also provided, the fuel supply from the first end to which the raw material vapor to the collection unit for collecting the fuel feed steam from the housing unit so as to be useful in fuel cell assemblies are coupled to the housing unit, the fuel cell assembly has a second end coupled to. Hydrocarbon, steam, vaporization rate, the pre-heater, the reforming pre-heating unit
A method and apparatus for use with an oxidizer assembly of a fuel cell system in which the oxidi... more A method and apparatus for use with an oxidizer assembly of a fuel cell system in which the oxidizer assembly has an oxidizing unit for oxidizing anode exhaust gas containing electrolyte particulates and is adapted or conditioned so as to enable the electrolyte particulates to be removable from the assembly and to be removed from the assembly, and wherein the conditioning and removing occur with the oxidizing unit retained in the oxidizer assembly. The fuel cell system is also adapted so that such conditioning and removing occur with the oxidizing assembly retained in the fuel cell system.
In fuel cells high, and as a pre-treatment assembly and a method for the treatment of a fuel feed... more In fuel cells high, and as a pre-treatment assembly and a method for the treatment of a fuel feedstock containing a hydrocarbon and oxygen have a lower hydrocarbon-containing material, wherein the pre-assembly is de-oxidation bed and fuel feedstock to reduce the oxygen in the fuel feedstock pre-reforming contains a bed, and the deoxygenation bed and said pre-reforming bed is a common reaction vessel to flow through the fuel supply after the raw material is first flowed through a deoxygenation bed, said pre-reforming bed to reduce the higher hydrocarbons containing water and it is arranged in the. The pre-reforming assembly may include propane processing bed for processing propane and propylene in the additional fuel feedstock to, those propane processing bed is arranged in a common reaction vessel with the deoxygenation bed and said pre-reforming bed. Pre-assembly, fuel cell, deoxygenation bed, pre-reforming bed, propane processing bed
An oxidizer catalyst assembly for use in a fuel cell system for oxidizing anode exhaust gas and i... more An oxidizer catalyst assembly for use in a fuel cell system for oxidizing anode exhaust gas and in which a first catalyst member is situated along a gas flow path and a second catalyst member is situated along the gas flow path following the first catalyst member. Each of the catalyst members includes a plurality of channels for passing the gas therethrough and an oxidizing catalyst deposited in the channels. The channel density of the channels of the second catalyst member is greater than the channel density of the channels of the first catalyst member and the channel width of the channels of the second catalyst member is less than the channel width of the channels of the first catalyst member.
Abstract In this paper, we investigated the use of Ni 19.5 -Ru 0.05 /CGO as catalysts for associa... more Abstract In this paper, we investigated the use of Ni 19.5 -Ru 0.05 /CGO as catalysts for associated gas pre-reforming to convert higher hydrocarbon and obtain higher methane content. To increase the content of methane, we perform catalytic pre-reforming experiments at 8 bars. Ni-Ru/CGO fully converted the C 2 –C 5 hydrocarbons at 500 °C. However, the conversion of C2–C5 hydrocarbons decreased from 100% to 80% as the SCR decreased from 3.0 to 1.0. Catalytic degradation occurred at temperatures below 300 °C. Comparing the commercial pre-reforming catalyst (C11PR, produced by Sud-Chemie) with Ni-Ru/CGO catalysts, Ni-Ru/CGO outperformed C11PR under the same conditions. We performed long-term tests with Ni-Ru/CGO. Each long-term test lasted over 900 h. Initially, the methane yield was approximately 60%, and the higher hydrocarbons were fully converted. After 900 h, the methane yield was approximately 55%, and dramatically reaching to 50% at 920 h. Simultaneously, the C 2 –C 5 hydrocarbon yield increased to approximately 8%. After the long-term test, we analyzed the tested catalysts and determined that catalytic degradation occurred due to carbon deposition on the catalyst surface.
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Papers by Sai Katikaneni