Kinetic and mechanistic studies of Fischer-Tropsch synthesis over the nano-structured iron-cobalt-manganese catalyst prepared by hydrothermal procedure

•Kinetic studies over the nano-structured Fe-Co-Mn catalyst was investigated.•The rate-determining step proceeds via reaction both dissociative adsorbed CO and dissociative adsorbed H2 on the catalyst surface.•The activation energy was found to be 85.18 kJ/mol for the best model.

The present research work is focused on the kinetic and mechanistic studies of the Fischer-Tropsch synthesis in a fixed bed micro reactor; over the nano-structured iron-cobalt-manganese catalyst prepared by hydrothermal procedure. Experimental conditions within the reactor were varied as follows: T = 265-330 °C, P = 1.2-10 bar, H2/CO feed ratio = 0.5-2 and GHSV = 4200 h−1. Based on Langmuir-Hinshelwood-Hogan-Watson and Eley-Rideal adsorption theories in catalytic processes, 18 kinetic models for CO consumption were tested and interaction between dissociative adsorbed carbon monoxide and dissociative adsorbed hydrogen as the rate-determining step gave the best fitted kinetic model -rCO=kPbCOPCObH2PH221+2bCOPCO0.5+bH2PH20.56. The Levenberg-Marquardt algorithm was used to estimate the kinetic parameters and the obtained activation energy was 85.18 kJ/mol for the optimal kinetic model. Characterization of catalysts was performed using XRD, FESEM, EDS, TEM and the N2 adsorption-desorption measurements such as BET and BJH methods.

Graphical abstractKinetic and mechanistic studies of Fischer-Tropsch synthesis over the nano-structured iron-cobalt-manganese catalyst prepared by hydrothermal procedure.Download high-res image (63KB)Download full-size image