TITLE: Fischer-Tropsch-Synthese am Katalysatorsystem Mangan-Eisen bei mittleren Synthesedruecken. (Fischer-Tropsch synthesis in the Mn-Fe catalyst system at medium synthesis pressures) AUTHOR: K. Müller. INST. AUTHOR: Technische Univ. Berlin (Germany, F.R.). Fachbereich 6 - Physikalische und Angewandte Chemie. LANGUAGE: German PUB. TYPE: Technical Report PUB. COUNTRY: Germany Federal Republic SOURCE: Other [$TFFIZ], 5 Feb 86, 172p. NTIS ORDER NO.: TIB/B89-81030/INW NOTES: Diss. (Dr.-Ing.) In German, ABSTRACT: The efficiency of a coal-upgrading plant working according to the Fischer-Tropsch method can be improved by the use of modern coal gasifiers if the conversion of the synthesis gases with a high content of carbon oxide is achieved directly and at the working pressure of the gasifier. Therefore, investigations were made to find out whether the manganese-iron catalyst system developed by Koebel and Tillmetz in 1975 has sufficiently good synthesis qualities under these conditions and can be used for the execution of such a synthesis. Synthesis gases with CO/H2 ratios of between 1 and 1.7 were converted at total synthesis pressures of 0.85 to 9.4 MPa in a fixed bed reactor with internal reactor gas cycle and in an agitated liquid phase reactor. An increase of the pressure from 0.85 MPa to 4 to 5 MPa leads, at a constant retention time of the reaction gas, to a clear increase in the synthesis gas consumption rate in both reactors. Above 4 to 5 MPa the activity of the investigated catalyst remains almost constant at a further increase of the pressure. Hence it follows that the manganese-iron catalyst can be used for the medium-pressure synthesis. The velocity data obtained in the gradientless fixed bed reactor are described best by those kinetic approaches in which the coverage of the catalyst surface by the reaction products water and carbon dioxide is taken into consideration. (orig.). (Copyright (c) 1989 by FIZ. Citation no. 89:081030.) |