THE DISTRIBUTION OF THE PRODUCTS OF FISCHER-TROPSCH SYNTHESIS WITH IRON CATALYSTS

Abstract

The product distribution of Iron-catalysts of different hydrogenation hydrogen values is presented and investigated with the application of the polymerisation function. A law of distribution is found for the paraffin hydrocarbons. The volumes of C-fractions IOllow the reciprocal proportional ratios of the squares of the C-numbers, independent of the absolute values of the hydrogenation hydrogen. Their absolute values are obtained by multiplication with hydrogenation hydrogen values. The methane formation is an exception from the rule. The minimum value of the first methane term in the series of the paraffin distribution is being estimated, and the influence of the methane formation on the formation of the higher paraffin hydrocarbons is being discussed. The paraffin distribution for different catalysts can be calculated with the help of simple data, obtained from gas analyses.A similar law of distribution is stated for olefines. This distribution decreases for the higher olefines in a higher order, than in the reciprocal square ratios of the C-numbers. The formation of lighter olefines is favoured against the formation or preservation of the higher olefines,probably on account of the easier hydrogenation of the higher olefines. Quantitative data are given which lead to the calculation of the olefine distribution for iron catalysts.The formation of the olefines is found to be principally a radical polymerisation  which is superimposed by a lesser active ethylene polymerisation.According to the amount of hydrogenation hydrogen, activated by a catalyst, smaller or larger parts of the polymerisation olefines are being hydrogenated. The methane formation occurs at least to somewhat more than  of the hydrogenation hydrogen value. The change in the formation of the higher paraffins with increasing methane formation is discussed in detail. A method is indicated according to which the total olefine volume and the division of CO-volumes, converted into paraffin and olefine hydrocarbons, can be calculated.