Fischer-Tropsch upgrading

Goal Upgrading via Fischer-Tropsch. The synthesis of methane by the catalytic reduction of carbon monoxide and hydrogen over nickel and cobalt catalysts at atmospheric pressure was reported in 1902 (11). 

Natural Gas Upgrading via Fischer-Tropsch. In the United States, as in other countries, scarcities from World War II revived interest in the synthesis of fuel substances. A study of the economics of Fischer synthesis led to the conclusion that the large-scale production of gasoline from natural gas offered hope for commercial utiHty. In the Hydrocol process (Hydrocarbon Research, Inc.) natural gas was treated with high purity oxygen to produce the synthesis gas which was converted in fluidized beds of kon catalysts (42). 

This effort was funded by the National Aeronautics and Space Administration (NASA) Grant NNX07AB93A under a project entitled Basic Studies for the Production and Upgrading of Fischer-Tropsch Synthesis Products to Fuels and the Commonwealth of Kentucky. This research was carried out, in part, at the National Synchrotron Light Source, Brookhaven National Laboratory, which is supported by the U.S. DOE, Divisions of Materials Science and Chemical Sciences. Special thanks to Dr. Nebojsa Marinkovic (Beamline X18b, NSLS, Brookhaven) for help with X AFS studies and Joel Young (University of Oklahoma, Department of Physics) for XAFS cell construction. 

Olefins in the C3-320°C range had significant synthetic value, and additional olefins were produced by thermal cracking in some facilities. Acid-catalyzed and thermal olefin oligomerization were important technologies for the upgrading of Fischer-Tropsch products. 

Freerks, R. 2003. Early efforts to upgrade Fischer-Tropsch reaction products into fuels, lubricants and useful materials. Paper presented at the AIChE Spring National Meeting, New Orleans, 86d. 

Conversion of lignocellulose into transportation fuels via pyrolysis and subsequent oil upgrading [72], via gasification and subsequent Fischer-Tropsch or methanol synthesis [3], via hydrolysis and subsequent fermentation to ethanol or subsequent conversion into ethyl levulinate [45, 46, 73]. 

A particularly intriguing potential application of this reaction is the upgrading of the products of Fischer-Tropsch catalysis to increase the eventual yield of desirable n-aUcane chain lengths (typically C9-C19). FT catalysis, already practiced on a large scale commercially, may prove to be a key route to the future utilization of coal, biomass, or other nonpetroleum carbon sources (including CO2 reduction powered by solar, wind, or nuclear energy) [51, 52]. 

If the gasifier product stream is intended for downstream use as the feedstock for further upgrading such as methanation, methanol or Fischer Tropsch synthesis, very thorough desulphuri-sation is essential since the catalysts in these upgrading processes are highly sensitive to sulphur poisoning. The methanation catalysts normally cannot tolerate more than 0.05 ppm of sulphur in the feedstock. In addition to H2S sulphur values in the gasifier product it may contain COS, CS2, mercaptans and thiophenes. These are normally removed by activated carbon or zinc oxide filters ahead of the sensitive synthesis catalyst beds. 

The director of this Institute, Dr. Herbert Kolbel, Professor of Technical Chemistry, has been involved during the second World War II in the development of upgrading coal to other hydrocarbons according to the Fischer-Tropsch synthesis in bubble column reactors with suspended catalysts. He was interested in gaining more knowledge s on of transport processes and chemical reactions in these reactors. 

Combination of Fischer-Tropsch synthesis and acid catalysis Methane activation (natural gas upgrading) ... 

Dimerization and codimerization reactions are widely used on an industrial scale either to provide chemicals of high added value or to upgrade by-product olefinic streams coming from various hydrocarbon cracking processes (steam or catalytic cracking) or hydrocarbon forming processes (Fischer-Tropsch synthesis or methanol condensation) (e. g., according to eq. (1)). 

An obvious new source of highly refined waxes is from Fischer-Tropsch wax—this type of wax is already on the market from Shell s Bintulu plant in Malaysia, and it undoubtedly will be upgraded, if it has not been already, to meet FDA standards and equivalent ones from other countries. It will be unique in its properties because of the near-complete absence of isoparaffins and the heavy waxes will contain no naphthene components that give microcrystalline waxes their properties. 

R. Freerks, Early Efforts to Upgrade Fischer-Tropsch Reaction Products into Fuels, Lubricants and Useful Materials, Paper 86d, presented at the American Institute of Chemical Engineers Spring National Meeting, New Orleans, April 2, 2003. 

XTL technology (X to liqtiids with X as coal, biomass, or natural gas etc.) based on Fischer-Tropsch consists of three major parts, syngas generation, ETS, and product upgrading. Figure 6.11.9 shows different configurations of an XTL plant with low or high temperature FTS. 

Equation (2.7) represents the low-temperature version of the Fischer-Tropsch synthesis using a cobalt-based catalyst at H2/CO ratios of 1.3-1.7. The reaction takes place at 200-260 °C and 20-40 bar producing a broad spectrum of straight-chain olefins and paraffins free from aromatics and hetero-atoms. Hydrogenation is typically used as further upgrading step requiring additional hydrogen. The final products are used as solvents, waxes, or fractions of kerosene or diesel fuel [3,27,28]. 

Synfining A process for upgrading Fischer-Tropsch liquid hydrocarbons into middle distillate products such as synthetic diesel and jet fuels. Developed by Syntroleum Corp. since 1984. See also Bio-Synfining. 

Presently the major step in the GTL conversion is considered to be the Fischer-Tropsch synthesis of hydrocarbons from synthesis gas (CO-I-H ). The classical processes produce waxes (solid hydrocarbons) that are further upgraded into the components of liquid fuels (gasoline, diesel). Diesel production by this technology seems to be the best solution. The synthetic diesel fuel has better characteristics compared to the fuel grades produced from oil (standard EN-590) the cetane number is 75 (versus 55 for the oil-derived diesel) the content of polynuclear aromatic compounds is 0.1 (versus 6%) the sulfur content is 0 ppm (versus 50 ppm). Such synthetic fuels can be used as additives to the oil-based diesel. GTL-diesel is used in Germany, Austria, and Sweden and the blends of the synthetic fuel and conventional diesel are used in France, Italy, and other countries. 

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