View source for Fischer-Tropsch process

The '''Fischer-Tropsch process''' is a [[catalyst|catalyzed]] [[chemistry|chemical reaction]] in which [[carbon monoxide]] and [[hydrogen]] are converted into liquid [[hydrocarbon]]s of various forms. Typical catalysts used are based on [[iron]] and [[cobalt]]. The principal purpose of this process is to produce a synthetic [[petroleum]] substitute, typically from [[coal]] or [[natural gas]], for use as [[synthetic oil|synthetic lubrication oil]] or as [[synthetic fuel]].  

==Original process==
The original Fischer-Tropsch process is described by the following [[chemical equation]] (where 'n' is a [[positive integer]]):

:(2n+1)[[hydrogen|H<sub>2</sub>]] + n[[carbon monoxide|CO]] → [[alkane|C<sub>n</sub>H<sub>(2n+2)</sub>]] + n[[water (molecule)|H<sub>2</sub>O]]

The initial reactants in the above reaction (i.e. CO and H<sub>2</sub>) can be produced by other reactions such as the partial combustion of a [[hydrocarbon]]:

:[[alkane|C<sub>n</sub>H<sub>(2n+2)</sub>]] + ½ n[[oxygen|O<sub>2</sub>]] → (n+1)[[hydrogen|H<sub>2</sub>]] + n[[carbon monoxide|CO]]

for example (when n=1), [[methane]] (in the case of gas to liquids applications):

:[[methane|2CH<sub>4</sub>]] + [[oxygen|O<sub>2</sub>]] → 4H<sub>2</sub> + 2CO

or by the [[gasification]] of coal or biomass:

:C + H<sub>2</sub>O → H<sub>2</sub> + CO

The energy needed for this [[endothermic]] reaction of coal or biomass and steam is usually provided by ([[exothermic]]) combustion with air or oxygen. This leads to the following reaction:

:2C + O<sub>2</sub> → 2CO

The mixture of [[carbon monoxide]] and [[hydrogen]] is called [[synthesis gas]] or syngas.
The resulting hydrocarbon products are refined to produce the desired [[synthetic fuel]].

The carbon dioxide and carbon monoxide is generated by partial oxidation of [[coal]] and [[wood]]-based fuels. The utility of the process is primarily in its role in producing [[fluid]] [[hydrocarbon]]s from a solid feedstock, such as [[coal]] or [[solid]] [[carbon]]-containing wastes of various types.  Non-[[oxidation|oxidative]] [[pyrolysis]] of the solid material produces syngas which can be used directly as a fuel without being taken through Fischer-Tropsch transformations.  If [[liquid]] petroleum-like fuel, lubricant, or wax is required, the Fischer-Tropsch process can be applied.

==History==
Since the invention of the original process by the German researchers [[Franz Joseph Emil Fischer|Franz Fischer]] and [[Hans Tropsch]], working at the [[Kaiser Wilhelm Institute]] in the [[1920s]], many refinements and adjustments have been made, and the term "Fischer-Tropsch" now applies to a wide variety of similar processes ('''Fischer-Tropsch synthesis''' or '''Fischer-Tropsch chemistry''') 

The process was invented in [[petroleum]]-poor but [[coal]]-rich [[Germany]] in the 1920s, to produce [[liquid fuel]]s. It was used by [[Germany]] and [[Japan]] during [[World War II]] to produce ''[[ersatz]]'' fuels. Germany's annual [[synthetic fuel]] production reached more than 124,000 barrels per day from 25 plants ~ 6.5 million tons in 1944.<ref>[http://www.fe.doe.gov/aboutus/history/syntheticfuels_history.html "The Early Days of Coal Research", USDOE]</ref>

After the war, captured German scientists recruited in [[Operation Paperclip]] continued to work on synthetic fuels in the [[United States]] in a [[United States Bureau of Mines]] program initiated by the [[Synthetic Liquid Fuels Act]].

==Utilization==
[[Image:Holzvergasung.jpg|200px|thumb|right|Fluidized Bed Gasification with FT-pilot in [[Güssing]], [[Burgenland]], [[Austria]]]]
[[Image:FT_kolonne.jpg|200px|thumb|right|FT-pilot in Güssing, Burgenland, Austria]]
Currently, only a handful of companies have commercialised their FT technology. 
#[[Royal Dutch Shell|Shell]] in [[Bintulu]], [[Malaysia]], uses [[natural gas]] as a [[feedstock]], and produces primarily low-[[sulfur]] [[diesel]] fuels and food-grade wax.  
#[[Sasol]] in [[South Africa]] uses [[coal]] and natural gas as a feedstock, and produces a variety of synthetic petroleum products. Sasol produces most of the country's [[diesel]] fuel.

The process was used in South Africa to meet its energy needs during its isolation under [[Apartheid]]. This process has received renewed attention in the quest to produce low-sulfur diesel fuel in order to minimize [[the environment]]al impact from the use of [[diesel engine]]s. 

A small US-based company, [[Rentech]], is currently focusing on converting nitrogen-fertiliser plants from using a natural gas feedstock to using coal or [[coke (fuel)|coke]], and producing liquid hydrocarbons as a by-product.

Also Choren Industries in Germany, CWT ([[Thermal depolymerization|Changing World Technologies]]) and the GTL Corporation have built FT plants or use similar processes.<ref>[http://www.choren.com Choren official web site]</ref><ref>[http://www.technologyreview.com/BizTech/wtr_15923,296,p1.html MIT Technology Review]</ref> The GTL Corporation employ a [[micro-GTL]] process that is compact in that their equipment is used directly at natural gas well sites. Two [[Micro-GTL]] pilot plants have been successfully run and proven in Oklahoma by the GTL Corporation. 

The FT process is an established technology and already applied on a large scale, although its popularity is hampered by high capital costs, high operation and maintenance costs, and the uncertain and volatile price of [[crude oil]]. In particular, the use of natural gas as a feedstock only becomes practical when using "[[stranded gas reserve|stranded gas]]", i.e. sources of natural gas far from major cities which are impractical to exploit with conventional gas pipelines and LNG technology; otherwise, the direct sale of natural gas to consumers would become much more profitable. There are several companies developing the process to enable practical exploitation of so-called [[stranded gas reserve]]s. It is expected by geologists that supplies of [[natural gas]] will [[peak oil|peak]] 5-15 years after oil does, although such predictions are difficult to make and often highly uncertain.

There are large coal reserves which may increasingly be used as a fuel source during oil depletion. Since there are large coal reserves in the world, this technology could be used as an interim transportation fuel if conventional oil were to become more expensive. Combination of [[biomass gasification]] (BG) and Fischer-Tropsch (FT) synthesis is a very promising route to produce renewable or ‘green’ transportation fuels.

In Sept. 2005, [[Pennsylvania]] governor [[Edward Rendell]] announced a venture with Waste Management and Processors Inc. - using technology licensed from Shell and Sasol - to build an FT plant that will convert so-called waste coal (leftovers from the mining process) into low-sulfur diesel fuel at a site outside of [[Mahanoy City]], northwest of [[Philadelphia]].<ref>[http://www.state.pa.us/papower/cwp/view.asp?Q=446127&A=11 "GOVERNOR RENDELL LEADS WITH INNOVATIVE SOLUTION TO HELP ADDRESS PA ENERGY NEEDS; REDUCES DEPENDENCE ON FOREIGN SUPPLIES, State of Pennsylvania website]</ref> The state of Pennsylvania has committed to buy a significant percentage of the plant's output and, together with the U.S. Dept. of Energy, has offered over $140 million in tax incentives. Other coal-producing states are exploring similar plans. Governor [[Brian Schweitzer]] of [[Montana]] has proposed developing a plant that would use the FT process to turn his state's coal reserves into fuel in order to help alleviate the United States' dependence on foreign oil. <ref>[http://www.billingsgazette.com/index.php?id=1&display=rednews/2005/08/02/build/state/25-coal-fuel.inc "Schweitzer wants to convert Otter Creek coal into liquid fuel", ''Billings Gazette, [[August 2]] [[2005]], accessed [[August 13]] [[2007]]]</ref>

In Oct. 2006, [[Finland|Finnish]] paper and pulp manufacturer [[UPM (company)|UPM]] announced its plans to produce biodiesel by Fischer-Tropsch process alongside the manufacturing processes at its European paper and pulp plants, using waste biomass resulted by paper and pulp manufacturing processes as source material. <ref>[http://newsroom.finland.fi/stt/showarticle.asp?intNWSAID=14179&group=Business "UPM-Kymmene says to establish beachhead in biodiesel market", ''NewsRoom Finland'']</ref>

In August 2007, [[Louisiana State University]] announced they had received funding from the US [[Department of Energy]] and [[Conoco Phillips]] for development of new nanotechnologies for catalysis of coal syngas to ethanol conversion.<ref>[http://appl003.lsu.edu/unv002.nsf/(NoteID)/16C8C6DDB626B2E0862573360056D0A6?OpenDocument LSU research]</ref>

===U.S. Air Force certification===
[[Syntroleum]], a publicly traded US company (Nasdaq: SYNM) has produced over 400,000 gallons of diesel and jet fuel from the Fischer-Tropsch process at its demonstration plant near Tulsa, Oklahoma. Syntroleum is working to commercialize its proprietary Fischer-Tropsch technology via coal-to-liquid plants in the US, China, and Germany, as well as gas-to-liquid plants internationally. Using natural gas as a feedstock, the ultra-clean, low sulfur fuel has been tested extensively by the US Department of Energy, the Department of Transportation, and most recently, Syntroleum has been working with the [[U. S. Air Force]] to develop a synthetic jet fuel blend that will help the Air Force to reduce its dependence on imported petroleum. The Air Force, which is the U.S. military's largest user of fuel, began exploring alternative fuel sources in 1999. On December 15, 2006, a [[B-52]] took off from [[Edwards AFB]] for the first time powered solely by a 50-50 blend of [[JP-8]] and Syntroleum's FT fuel. The seven-hour flight test was considered a success. The goal of the flight test program is to qualify the fuel blend for fleet use on the service's B-52s, and then flight test and qualification on other aircraft.<ref name="anr1"/>

On [[August 8]] [[2007]], [[United States Secretary of the Air Force|Air Force Secretary]] [[Michael Wynne]] certified the B-52H as fully approved to use the FT blend, marking the formal conclusion of the test program.<ref name=anr2>Hernandez, Jason, "SECAF certifies synthetic fuel blends for B-52H", ''Aerotech News and Review'', [[August 10]] [[2007]]</ref>

This program is part of the [[Department of Defense]] Assured Fuel Initiative, an effort to develop secure domestic sources for the military energy needs. The Pentagon hopes to reduce its use of crude oil from foreign producers and obtain about half of its aviation fuel from alternative sources by 2016.<ref name="anr1">Zamorano, Marti, "B-52 synthetic fuel testing: Center commander pilots first Air Force B-52 flight using solely synthetic fuel blend in all eight engines", ''Aerotech News and Review'',[[22 December]] [[2006]]</ref> With the B-52 now approved to use the FT blend, the USAF will use the test protocols developed during the program to certify the [[C-17 Globemaster III]] and then the [[B-1 Lancer|B-1B]] to use the fuel. The Air Force intends to test and certify every airframe in its inventory to use the fuel by 2011.<ref name=anr2/>

==Environmental concerns==
One issue that has yet to be addressed in the emerging discussion about large-scale development of synthetic fuels is the enormous increase in primary energy use and carbon emissions inherent in conversion of gaseous and solid carbon sources to a usable liquid form, assuming the energy used to drive the process comes from burning coal or hydrocarbon fuels. Recent work by the National Renewable Energy Laboratory indicates that full fuel cycle greenhouse gas emissions for coal-based synfuels are nearly twice as high as their petroleum-based equivalent. Emissions of other pollutants are vastly increased as well, although many of these emissions can be captured during production. [[Carbon sequestration]] has been suggested as a mitigation strategy for greenhouse gas emissions. While sequestration is already in limited use, there is limited incentive in the absence of a [[carbon tax]] or [[emissions trading|emissions cap]].

However, [[biomass gasification]] technology offers a carbon-neutral alternative. Biomass-powered synthetic fuel plants are one of the most technologically and economically convincing energy possibilities for a carbon-neutral economy, according to the paper ''Carbon cycle management with increased photo-synthesis and long-term sinks'', from a recent climate change conference sponsored by the Royal Society Of New Zealand.<ref>[http://www.rsnz.org/topics/energy/ccmgmt.php#2 "Carbon cycle management with increased photo-synthesis and long-term sinks"]</ref>

Hybrid hydrogen-carbon processes have also been proposed recently<ref>{{cite journal | author = R. Agrawal, N. R. Singh, F. H. Ribeiro and W. N. Delgass | title = Sustainable fuel for the transportation sector | year = 2007 | journal = [[PNAS]] | volume = 104 | issue = 12 | pages = 4828-4833 | doi = 10.1073/pnas.0609921104}}</ref> as another closed-carbon cycle alternative combining 'clean' electricity, recycled CO, H<sub>2</sub> and captured CO<sub>2</sub> with biomass as inputs as a way of reducing the biomass needed.

== See also ==
{{EnergyPortal}}
* [[Abiogenic petroleum origin]]
* [[Bergius process]]
* [[Biomass to liquid]]
* [[Future energy development]]
* [[Hubbert peak]]
* [[Karrick process]]
* [[Non-conventional oil]]
* [[Synthetic Liquid Fuels Program]]
* [[Thomas Gold]]
* [[Wood gas]]

==References==
{{reflist|2}}

== External links ==
* [http://www.fischer-tropsch.org/ Fischer-Tropsch Archive ]
* [http://www.aapg.org/explorer/2002/11nov/abiogenic.cfm Abiogenic Gas Debate 11:2002 (EXPLORER)]
* [http://www.spe.org/elibinfo/eLibrary_Papers/spe/1982/82UGR/00010836/00010836.htm Unconventional Ideas About Unconventional Gas (Society of Petroleum Engineers)]
* ''[http://www.fischer-tropsch.org/primary_documents/patents/GB/gb309002.pdf Process of synthesis of liquid hydrocarbons]'' - Great Britain patent GB309002 - [[Hermann Plauson]]
* ''[http://www.technologyreview.com/read_article.aspx?id=16713&ch=biztech Clean Diesel from Coal]'' by Kevin Bullis
* ''[http://tbp.org/pages/Publications/Bent/Features/Su07Uhrig.pdf Implementing the “Hydrogen Economy” with Synfuels (pdf)]''

[[Category:Chemical reactions]]
[[Category:Chemical processes]]
[[Category:Chemical engineering]]
[[Category:Coal]]
[[Category:Petroleum production]]
[[Category:Organometallic chemistry]]
[[Category:Peak oil]]
[[Category:Unit processes]]

[[ca:Procés Fischer-Tropsch]]
[[cs:Fisher-Tropschova syntéza]]
[[da:Fischer-Tropsch proces]]
[[de:Fischer-Tropsch-Synthese]]
[[es:Proceso Fischer-Tropsch]]
[[eo:Procezo de Fiŝer-Tropŝ]]
[[fr:Procédé Fischer-Tropsch]]
[[nl:Fischer-Tropschbrandstoffen]]
[[ja:フィッシャー・トロプシュ法]]
[[no:Fischer-Tropsch-prosessen]]
[[pl:Synteza Fischera-Tropscha]]
[[pt:Processo de Fischer-Tropsch]]
[[ru:Синтез Фишера — Тропша]]
[[sk:Fischerov-Tropschov proces]]
[[fi:Fischer-Tropsch-menetelmä]]
[[sv:Fischer-Tropsch-processen]]
{{WikiDoc Sources}}