10. Products from Fischer-Tropsch Plants.
(See also reference I(a)/12 and I(a)/13 at end of this section).
During the last years the use of primary Fischer products was of course governed by wartime necessity. In general, it may be stated that a peaceful development would probably have led to the eventual disappearance of the FT product from the fuel picture, with the possible exception of the Diesel cut. Yet it was just this fraction that was also the starting material for a number of syntheses. As to the value of the diesel oil, it remains to be seen whether FT oil may have other special properties which are not yet recognized today, which make it highly desirable as a diesel fuel. The cetane number is, of course, known to be high (90-100). In Germany the fuels were used exclusively to blend up certain low cetane stocks like coal tar oil.
The properties of the LP and Mp cobalt synthesis are well known and listed below:
(1) “Gasol-Fluessiggas” C3 and C4. The olefine content is fairly high as shown on the next page:
LP gasol contains 50-55% olefines
MP gasol contains 25-30% olefines
Kreislauf would have produced 80% olefine in this fraction. The ratio of C3:C4 is approximately 1:1, with the butane cut containing 1-2% isobutene. This gas is used widely in Germany as a motor fuel and is bottled in the plants.