Study on Deactivation of Co/ZrO2/SiO2 Catalyst For Fischer-Tropsch Synthesis

Abstract

A Co/ZrO2 /SiO2 catalyst active for synthesis of heavy hydrocarbons from syngas was subjected to a stability test of 500 h on a laboratory scale. The catalyst showed a considerable decrease in CO conversion, while the hydrocarbon distribution hardly changed with time on stream. The regeneration of deactivated catalyst with H2 at 673 K partially restored the activity. XRD, FT-IR and TGA identified a hydrated cobalt silicate species in the catalyst near the reactor outlet. Thus, the cause of deactivation was proposed mainly to be the formation of inactive hydrated silicate between Co metal and silica in presence of high partial pressure of water.