Fischer-Tropsch - University of Maryland
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Transcript Fischer-Tropsch - University of Maryland
Fisher-Tropsch Process
Adnan Bashir
Bin Divakaransantha
Prakash Poudel
Semir Kelifa
Department of Chemical and Bio molecular Engineering,
University of Maryland
CHBE446
February 05, 2015
Outline
Intro/Historical Background
Definition
Reaction type/Mechanism
Use/Industrial Importance
Technology/Reactors
Catalysis
Conclusion
History
Sabatien & Senderens (1902)
produced mixture of hydrocarbons
Not favorable at the time
No single product formed
Priority given to methanol and
ammonia
History Cont.
Fischer and Tropsch
Used base catalyst like alkalized
iron and produced “synthol”
Temperature of about 400-450
Celsius and 150 atm
Higher hydrogen to CO ratio
produced better product
Tested this fluid like substance in
1922 NSU motorbike
Seated 2 people and outperformed
reference fuel
Catalyst video
History Cont..
Tested this fluid like substance in 1922
NSU motorbike
Seated 2 people and outperformed
reference fuel
Encouraging performance led to World
War II fuel supply
Fist plant made in Germany in 1934
By 1938 660,000 tons per-anum
produced
Source: http://wiredspace.wits.ac.za/jspui/bitstream/10539/11587/4/Chapter%202%20-%20Literature%20review%20-%20FTS.pdf
Reaction steps
Associative
adsorption of CO and splitting of C/O bon
Dissociative adsorption of 2H2
Transfer of 2H to the oxygen to yield H2O
Desorption of H2O
Transfer of 2H to the carbon to yield CH2
Main reactions
Alkane formation
𝑛𝐶𝑂 + 2𝑛 + 1 𝐻2 → 𝐶𝑛 𝐻2𝑛+2 + 𝑛𝐻2 𝑂
Favored by high 𝐻2 /CO ratio
Strong hydrogenating catalyst is needed.
Alkene formation
𝑛𝐶𝑂 + 2𝑛𝐻2 → 𝐶𝑛 𝐻2𝑛 + 𝑛𝐻2 𝑂
Favored by low 𝐻2 /CO ratio .
Less strong hydrogenating catalyst is needed.
Main reactions cont..
Water-gas-shift reaction
𝐶𝑂 + 𝐻2 𝑂 → 𝐶𝑂2 + 𝐻2
WGS activity is high in iron catalyst and
low in cobalt or ruthenium catalyst.
Helpful to adjust 𝐻2 /CO ratio.
Useful Products
Source: http://large.stanford.edu/courses/2010/ph240/liu1/
Gas-to-liquids (GTL)
Biomass-to-liquids (BTL)
Coal to liquid (CTL)
Can be used to produce
I.
Deiseal Fuel/Jet
Fuel/Kerosene
II.
Waxes/Lubricants
III.
Naphtha/Gasoline/Detergent
Technology/ Reactors
Fixed Bed Reactors
Originally used
Challenges associated with
removal of heat
Fluidized Bed Reactors
Better temperature control
High yields for Gasoline and
light products
Source:http://www.altenergymag.com/emagazine/2014/02/india-sustainable-communities-proposal/2216
http://pubs.rsc.org/en/content/articlelanding/2015/cy/c4cy01547a#!divAbstract
Technology cont..
Slurry Reactors
Small catalyst particles
suspended in a liquid
with low vapor
pressure
Low Temperature
Flexible design
High yield for waxes
Source:http://www.altenergymag.com/emagazine/2014/02/india-sustainable-communities-proposal/2216
Catalysis
Based on Transition Metals
Iron(Fe)
-Low Cost
-Higher Water Gas Shift activity
-Suitable for lower syngas(H2/CO)
Cobalt(Co)
-More Active
-Less Water Gas Shift activity
-Higher Cost
Source:http://periodictable.com/Elements/027/
Catalysis cont..
Nickel(Ni)
-Promotes Methane
formation
-Generally not desired
I.
Ruthenium(Ru)
High molecular weight
Hydrocarbons
High Cost
Not generally used
I.
Source:http://periodictable.com/Elements/027/
Promoters
Fe Based Catalysts
- Promoted with Alkali metals
-to obtain high basicity, and to stabilize catalyst
-Higher alkali level higher the shift to longer chains
-Addition of copper: Enhances reducibility
Co Based Catalysts
-promoted with small amounts of noble metals
-reduces reduction temperature/pressure
-yields less olefins and oxygenated products
Cost
Source: http://www.tc2.ch.tum.de/fileadmin/tuchtc2/www/ICP1/ICP1_1314/9-FT_synthesis-
Conclusion
Process developed by Fischer and Tropsch
Many possibilities exist and it is still a research interest
Useful for production of clean energy and the future of
Biofuels
Different reactor technologies for different desirable
products
Catalysts utilized based on need and cost
Questions?
Sources
http://www.ebah.com.br/content/ABAAABOMcAL/fischer2013tropsch-catalysis-the-basis-for-anemerging-industry
http://wiredspace.wits.ac.za/jspui/bitstream/10539/11587/4/Chapter%202%20%20Literature%20review%20-%20FTS.pdf
http://en.wikipedia.org/wiki/Fischer%E2%80%93Tropsch_process
http://large.stanford.edu/courses/2010/ph240/liu1/
http://www.velocys.com/our_products_processes_ft.php
http://www.purdue.edu/discoverypark/energy/assets/pdfs/cctr/outreach/Basics1CoalGasification-Jun07.pdf
http://www.bp.com/content/dam/bp/pdf/Technology/Fischer_Tropsch_Technology.pdf
http://www.tc2.ch.tum.de/fileadmin/tuchtc2/www/ICP1/ICP1_1314/9-FT_synthesis-2013_PW.pdf
http://www.biofuelsdigest.com/bdigest/2012/11/20/little-big-tech-can-fischer-tropsch-technologywork-at-smaller-scale/
http://en.wikipedia.org/wiki/Fischer%E2%80%93Tropsch_process
http://www.netl.doe.gov/research/coal/energy-systems/gasification/gasifipedia/ftsynthesis
http://www.tc2.ch.tum.de/fileadmin/tuchtc2/www/ICP1/ICP1_1314/9-FT_synthesis-2013_PW.pdf