The Fischer—Tropsch reaction with supported ruthenium catalysts: Modelling and evaluation of the reaction rate equation for a fixed bed reactor

Abstract A mathematical model for a non-isothermal fixed bed reactor with supported ruthenium catalyst for the conversion of synthesis gas was developed and tested with experimental results. A two-dimensional pseudo-homogeneous model with the well-known power law for the reaction rate was found to be suitable after consideration of all the possible transport mechanisms occurring under conditions favouring the formation of useful gaseous, liquid and solid (waxes) hydrocarbons. The reaction rate was evaluated by a non-linear regression technique in order to demonstrate the validity of the equation and the associated constants for a fixed bed. It was found that the hydrogenation and/or polymerisation reactions occurring along the length of the fixed bed reactor influenced the reaction rate constants for the conversion of carbon monoxide conversion, whereas, the reaction rate constants for the formation of methane remained unaffected when compared with results obtained from a differential bed reactor. Reaction rate constants are also reported for the formation of a light gas fraction (C 2 to C 4 ).

[1]  Alan Robert McKenzie. Kirk.  An investigation into the Fischer-Tropsch synthesis over supported ruthenium in a stirred gas-solid reactor. , 1979 .

[2]  L. Young,et al.  Axial Dispersion in Nonisothermal Packed Bed Chemical Reactors , 1973 .

[3]  A. G. Piken,et al.  Heterogeneous methanation: initial rate of CO hydrogenation on supported ruthenium and nickel , 1974 .

[4]  Bruce A. Finlayson,et al.  Packed bed reactor analysis by orthogonal collocation , 1971 .

[5]  Kevin J. Smith,et al.  Fischer-Tropsch reaction studies with supported ruthenium catalysts. II: Effects of oxidative pretreatment at elevated temperatures , 1986 .

[6]  G. Bond,et al.  Catalysis, science and technology , 1983 .

[7]  Bohdan W. Wojciechowski,et al.  Studies of the fischer-tropsch synthesis on a cobalt catalyst II. Kinetics of carbon monoxide conversion to methane and to higher hydrocarbons , 1989 .

[8]  R. B. Anderson,et al.  Hydrogenation of carbon monoxide and carbon dioxide on supported ruthenium catalysts at moderate pressures. [Molecular weight of product decreases sharply with increasing H/CO ratio of feed gas] , 1965 .

[9]  Alexis T. Bell,et al.  The kinetics and mechanism of carbon monoxide hydrogenation over alumina-supported ruthenium , 1981 .

[10]  John G. Ekerdt,et al.  Synthesis of hydrocarbons from CO and H2 over silica-supported Ru: Reaction rate measurements and infrared spectra of adsorbed species , 1979 .

[11]  G. Froment,et al.  Chemical Reactor Analysis and Design , 1979 .

[12]  C. Bennett,et al.  Kinetics of the Fischer-Tropsch Reaction over Iron , 1979 .

[13]  D. Mears,et al.  Diagnostic criteria for heat transport limitations in fixed bed reactors , 1971 .

[14]  Robert F. Blanks.  Fischer-Tropsch synthesis gas conversion reactor , 1992 .

[15]  L. Tavlarides,et al.  Kinetics of the Fischer-Tropsch synthesis , 1983 .

[16]  Manfred Baerns,et al.  Prediction of the performance of catalytic fixed bed reactors for Fischer-Tropsch Synthesis , 1980 .

[17]  M. Vannice,et al.  The catalytic synthesis of hydrocarbons from H2CO mixtures over the group VIII metals: II. The kinetics of the methanation reaction over supported metals , 1975 .

[18]  P. L. Silveston,et al.  Steady-state study of the Fischer-Tropsch reaction , 1981 .

[19]  David Mautner Himmelblau,et al.  Process analysis by statistical methods , 1970 .

[20]  S. Reyes,et al.  Transport-enhanced α-olefin readsorption pathways in Ru-catalyzed hydrocarbon synthesis , 1991 .