Understanding Homogeneous and Heterogeneous Contributions to the Platinum-Catalyzed Partial Oxidation of Ethane in a Short-Contact-Time Reactor

Zerkle, David K.; Allendorf, Mark D.; Wolf, M.; Deutschmann, Olaf

doi:10.1006/jcat.2000.3009

Cited by 158 publications

(128 citation statements)

References 66 publications

Supporting

Mentioning

122

Contrasting

Unclassified

Order By: Relevance

“…The same was also attested when-in addition to the previous changes-the kinetic parameters of CO 2 (s) desorption (S23) were exchanged to those of Aghalayam et al (2003). The previous procedure was also repeated by including four new reactions from the work of Zerkle et al (2000), which were…”

Section: Impact Of Co 2 On the Catalytic Reactivitymentioning

confidence: 85%

EFFECTS OF H₂O AND CO₂DILUTION ON THE CATALYTIC AND GAS-PHASE COMBUSTION OF METHANE OVER PLATINUM AT ELEVATED PRESSURES

Reinke

Mantzaras

Bombach

et al. 2007

Combustion Science and Technology

View full text Add to dashboard Cite

The impact of large exhaust gas dilution (up to 59.5% H 2 O and 30.3% CO 2 per vol.) on the heterogeneous (catalytic) and homogeneous (gas-phase) steady combustion of fuel-lean CH 4 =O 2 =N 2 mixtures over platinum has been investigated experimentally and numerically at pressures of 5 to 14 bar. In situ, one-dimensional Raman measurements of major gas-phase species concentrations and planar laser induced fluorescence (LIF) of the OH radical were used to assess the heterogeneous and homogeneous combustion processes, respectively. Comparisons between measurements and and CO 2 dilution. The addition of water inhibits the catalytic reactivity due to the increase in the surface coverage of OH(s) that, in turn, reduces the available free platinum sites. This inhibition has been quantified in terms of operating pressure, temperature, and amount of water dilution through an appropriate one-step catalytic reaction for the complete oxidation of methane. Water promotes chemically the onset of homogeneous ignition, as it directly impacts the radical pool buildup. On the other hand, the chemical effect of CO 2 on either reaction pathway is negligible. The influence of H 2 O and CO 2 dilution to the coupling between the two reaction pathways is elucidated and implications for the application of catalytically stabilized combustion to new power generation cycles with large exhaust gas dilution are addressed.

show abstract

Section: Impact Of Co 2 On the Catalytic Reactivitymentioning

confidence: 85%

EFFECTS OF H₂O AND CO₂DILUTION ON THE CATALYTIC AND GAS-PHASE COMBUSTION OF METHANE OVER PLATINUM AT ELEVATED PRESSURES

Reinke

Mantzaras

Bombach

et al. 2007

Combustion Science and Technology

View full text Add to dashboard Cite

show abstract

“…In particular oxidation reactions over noble metals have been modeled extensively such as of hydrogen [38][39][40][41][42][43][44] , CO [45][46][47] , and methane [31,[48][49][50][51][52] and ethane [22,26,53,54] over Pt, formation of synthesis gas over Rh [52,55] . Lately, mechanisms have been established for more complex reaction systems, for instance, three-way catalysts [56] or Chemical Vapor Deposition (CVD) reactors for the formation of diamond [57,58] , silica [59] , and nanotubes [60] .…”

Section: B Development Of Multi-step Surface Reaction Mechanismsmentioning

confidence: 99%

“…If upstream heat conduction does not matter, parabolic approaches as the boundary layer approximation may be used [109] , otherwise an elliptic ansatz is needed [22,107] .…”

Section: Monolithic Reactorsmentioning

confidence: 99%

Computational Fluid Dynamics Simulation of Catalytic Reactors

Deutschmann

2008

Handbook of Heterogeneous Catalysis

Self Cite

View full text Add to dashboard Cite

Catalytic reactors are generally characterized by the complex interaction of various physical and chemical processes. Monolithic reactors can serve as example, in which partial oxidation and reforming of hydrocarbons, combustion of natural gas, and the reduction of pollutant emissions from automobiles are frequently carried out. Figure 1 illustrates the physics and chemistry in a catalytic combustion monolith that glows at a temperature of about 1300 K due to the exothermic oxidation reactions. In each channel of the monolith, the transport of momentum, energy, and chemical species occurs not only in flow (axial) direction, but also in radial direction. The reactants diffuse to the inner channel wall, which is coated with the catalytic material, where the gaseous species adsorb and react on the surface. The products and intermediates desorb and diffuse back into the bulk flow. Due to the high temperatures, the chemical species may also react homogeneously in the gas phase. In catalytic reactors, the catalyst material is often dispersed in porous structures like washcoats or pellets. Mass transport in the fluid phase and chemical reactions are then superimposed by diffusion of the species to the active catalytic centers in the pores. The temperature distribution depends on the interaction of heat convection and conduction in the fluid, heat release due to chemical reactions, heat transport in the solid material, and thermal radiation. If the feed conditions vary in time and space and/or heat transfer occurs between the reactor and the ambience, a non-uniform temperature distribution over the entire monolith will result, and the behavior will differ from channel to channel.Today, the challenge in catalysis is not only the development of new catalysts to synthesize a desired product, but also the understanding of the interaction of the catalyst with the surrounding reactive flow field. Sometimes, the exploitation of these interactions can lead to

show abstract

“…Carbon formation, which was not incorporated into the models was responsible for the experimentally observed change in reaction rates. The results for the H 2 /CO production, for the models developed by Deutschmann et al [12][13][14] and the one developed by Mhadeshwar et al [15], Hauptmann et al [16] are shown in Figure 5 below. The hydrogen production by this method is about 20% by mass fraction, which could work to be used on a gas turbine combustor.…”

Section: Chemical Equationmentioning

confidence: 99%

Reforming Technologies to Improve the Performance of Combustion Systems

Hassan

Khandelwal

2014

Aerospace

View full text Add to dashboard Cite

A large number of theoretical and experimental studies have shown that the performance of kerosene combustion increases significantly if combustion is being assisted by the addition of hydrogen to the fuel/air mixture during the combustion process. It reduces the amount of CO, CO 2 and NO x emissions, while increasing the flame stability limits. It also helps in bruning fuel/air mixtures at much leaner equivalence ratios. The same principle could be applied to gain benefits in gas turbine combustors. Hydrogen for this purpose could be produced by the reforming of hydrocarbon fuels using a reformer module. This paper presents key hydrogen reforming technologies which, by implementation in gas turbine combustors, hold potential for improving both their performance and service life.

show abstract

Understanding Homogeneous and Heterogeneous Contributions to the Platinum-Catalyzed Partial Oxidation of Ethane in a Short-Contact-Time Reactor

Cited by 158 publications

References 66 publications

EFFECTS OF H₂O AND CO₂DILUTION ON THE CATALYTIC AND GAS-PHASE COMBUSTION OF METHANE OVER PLATINUM AT ELEVATED PRESSURES

EFFECTS OF H₂O AND CO₂DILUTION ON THE CATALYTIC AND GAS-PHASE COMBUSTION OF METHANE OVER PLATINUM AT ELEVATED PRESSURES

Computational Fluid Dynamics Simulation of Catalytic Reactors

Reforming Technologies to Improve the Performance of Combustion Systems

Contact Info

Product

Resources

About

Understanding Homogeneous and Heterogeneous Contributions to the Platinum-Catalyzed Partial Oxidation of Ethane in a Short-Contact-Time Reactor

Cited by 158 publications

References 66 publications

EFFECTS OF H2O AND CO2DILUTION ON THE CATALYTIC AND GAS-PHASE COMBUSTION OF METHANE OVER PLATINUM AT ELEVATED PRESSURES

EFFECTS OF H2O AND CO2DILUTION ON THE CATALYTIC AND GAS-PHASE COMBUSTION OF METHANE OVER PLATINUM AT ELEVATED PRESSURES

Computational Fluid Dynamics Simulation of Catalytic Reactors

Reforming Technologies to Improve the Performance of Combustion Systems

Contact Info

Product

Resources

About

EFFECTS OF H₂O AND CO₂DILUTION ON THE CATALYTIC AND GAS-PHASE COMBUSTION OF METHANE OVER PLATINUM AT ELEVATED PRESSURES

EFFECTS OF H₂O AND CO₂DILUTION ON THE CATALYTIC AND GAS-PHASE COMBUSTION OF METHANE OVER PLATINUM AT ELEVATED PRESSURES