SLIDE 1
Overview
- Motivation
- Hypothesis
- Experimental Methods
- Results
- Conclusions
- Future Work
Plasma-Assisted Synthesis of Molybdenum Carbide Catalysts CARLOS - - PowerPoint PPT Presentation
Plasma-Assisted Synthesis of Molybdenum Carbide Catalysts CARLOS - - PowerPoint PPT Presentation
Plasma-Assisted Synthesis of Molybdenum Carbide Catalysts CARLOS LOPEZ & DANIELLE MEYERS Advisors: Profs. K. Brezinsky, A. Saveliev Overview Motivation Hypothesis Experimental Methods Results Conclusions Future Work
SLIDE 2
SLIDE 3
Background: Motivation
- Noble metal character
- Water-gas shift reaction
- PEM Fuel Cells
- Non-thermal Plasma
- Fourth state of matter
- Parameters
- Advantages
SLIDE 4
Why do we want to replace noble metals?
1 gram 10 %‘Platinum on carbon’ catalyst = $39 1 gram Molybdenum metal = $0.39 Disclaimer: Does not include diamonds
SLIDE 5
Hypothesis
- Plasma synthesized,
nanostructured molybdenum carbide is more active than commercial catalysts
SLIDE 6
Synthesis Apparatus
Top Chamber Electrostatic Particle Suspension Bottom Chamber Plasma and molybdenum carbide formation
Ethylene Argon Vacuum: Low Pressure
SLIDE 7
What happens in the plasma?
Ar+ Ar+ Ar+ Ar+ Ar+ Ar+
Argon C2H4
e- e- e- e-
Mo
C· C· C· C· Mo Mo Mo Mo H· H· H· H· H· H· H· H· H· Mo2C
SLIDE 8
Product Collection
Metal Mesh Filters Polycarbonate Filter Washers
SLIDE 9
Characterization
Transmission Electron Microscopy
- Atomic resolution
- Crystallography
SLIDE 10
TEM Preparation
To grind, or not to grind, that is the question…
SLIDE 11
Electron Microscopy Image Simulation
SLIDE 12
Catalytic Activity
2 2 catalyst 2
H CO O H CO + ⎯ ⎯ → ⎯ +
Water-gas shift
PFR
Comparison
CuO/ZnO MoC bulk
SLIDE 13
Catalytic Reactor
Coalescence and Condenser Filters Packed Catalyst Deionized Water Flow Gas Chromatograph
SLIDE 14
Characterization: TEM Results
20 cc/min ethylene Molybdenum metal Comparable magnification No film Mo metal Mo2C
SLIDE 15
*Low, Ke-Bin 2008
20 cc/min ground
Orthorhombic Structure
Electron Microscopy Image Simulation
SLIDE 16
EMIS continued…
Molybdenum Metal (ground)
Hexagonal Structure
SLIDE 17
Catalysis Troubleshooting
Leaks Coalescence
Filter
SLIDE 18
Catalytic Activity: CO(g) consumed
200 400 600 800 1000 1200 1400 1600 1800 2000 GC Peak Area
- f CO
(mV*sec) 20 cc Commercial MoC Bulk Control Catalyst Species
SLIDE 19
Conclusions and Future Work
Activation/Reduction Surface Composition
Analysis
Investigate Plasma
Parameters
SLIDE 20
Acknowledgments
National Science Foundation, REU Program Department of Defense Professor Kenneth Brezinsky
- Dr. Alexei Saveliev
Abby Saddawi: Graduate Research
Advisor/Rock Star
- Dr. Ke-Bin Low and Dr. Alan Nicholls
SLIDE 21
References
- Low, Ke-Bin. Crystallography Modeling (2008)
- Xiao, Tiancun, et al. Study of the Preparation and Catalytic Performace of Molybdenum
Carbide Catalysts Prepared with C2H2/H2 Carburizing Mixture. Journal of Catalysis, 211, pp 183-191 (2002)
- Claridge, John B. et al. New Catalysts for the Conversion of Methane to Synthesis Gas:
Molybdenum and Tungsten Carbide. Journal of Catalysis. 180, pp 85-100 (1998).
- Bouchy, Christophe. Et al. A new route to the metastable FCC molybdenum carbide α-
MoC1-x. Chem Comm, 16 Dec 1999.
- Choi, Jae Soon. Et al. Influence of the Degree of Carburization on the Denisty of Sites
and Hydrogenating Activity of Molybdenum Carbides. Journal of Catalysis. 193, pp 238-247 (2000).
- Fridman, Alexander and Kennedy, Lawrence A. ‘Plasma Physics and Engineering’, 2004,
New York, Taylor and Francis Books, Inc.
- Patt, Jeremy, et al. Molybdenum carbide catalysts for water-gas shift. Catalysis Letters,
65, pp 193-195 (2000)