Methane ignition catalyzed by in situ generated palladium nanoparticles

Journal Article · Mon Mar 15 00:00:00 EDT 2010 · Combustion and Flame

DOI:https://doi.org/10.1016/J.COMBUSTFLAME.2009.07.012· OSTI ID:21285630

Shimizu, T; Abid, A D; Poskrebyshev, G; Wang, H ^[1]; Nabity, J; Engel, J; Yu, J ^[2]; Wickham, D ^[3]; Van Devener, B; Anderson, S L ^[4]; Williams, S ^[5]

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1. Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA 90089 (United States)
2. TDA Research, Inc., 12345 W. 52nd Ave, Wheat Ridge, CO 80033 (United States)
3. Reaction Systems, LLC, 19039 E. Plaza Drive, Suite 290, Parker, CO 80134 (United States)
4. Department of Chemistry, University of Utah, Salt Lake City, UT 84112 (United States)
5. Air Force Research Laboratory, Mail Stop RZA, 1950 Fifth Street, WPAFB, OH 45433 (United States)

Catalytic ignition of methane over the surfaces of freely-suspended and in situ generated palladium nanoparticles was investigated experimentally and numerically. The experiments were conducted in a laminar flow reactor. The palladium precursor was a compound (Pd(THD){sub 2}, THD: 2,2,6,6-tetramethyl-3,5-heptanedione) dissolved in toluene and injected into the flow reactor as a fine aerosol, along with a methane-oxygen-nitrogen mixture. For experimental conditions chosen in this study, non-catalytic, homogeneous ignition was observed at a furnace temperature of {proportional_to}1123 K, whereas ignition of the same mixture with the precursor was found to be {proportional_to}973 K. In situ production of Pd/PdO nanoparticles was confirmed by scanning mobility, transmission electron microscopy and X-ray photoelectron spectroscopy analyses of particles collected at the reactor exit. The catalyst particle size distribution was log-normal. Depending on the precursor loading, the median diameter ranged from 10 to 30 nm. The mechanism behind catalytic ignition was examined using a combined gas-phase and gas-surface reaction model. Simulation results match the experiments closely and suggest that palladium nanocatalyst significantly shortens the ignition delay times of methane-air mixtures over a wide range of conditions. (author)

• OSTI ID: 21285630
• Journal Information: Combustion and Flame, Vol. 157, Issue 3; Other Information: Elsevier Ltd. All rights reserved; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
77 NANOSCIENCE AND NANOTECHNOLOGY
PALLADIUM
METHANE
IGNITION
MIXTURES
PARTICLE SIZE
PARTICLES
AEROSOLS
NANOSTRUCTURES
TOLUENE
PALLADIUM OXIDES
AIR
COMBUSTION
NITROGEN
OXYGEN
PRECURSOR
SURFACES
DISTRIBUTION
COMPUTERIZED SIMULATION
CATALYSTS
KETONES
TEMPERATURE RANGE 1000-4000 K
TEMPERATURE RANGE 0400-1000 K
Catalytic combustion
Gas-surface reactions
Kinetic modeling
Particle size distribution