Avaliação de catalisadores de Co/Nb2O5 na Síntese de Fischer-Tropsch em reator de leito de lama agitado

Abstract

Motivated by the search of alternative sources of production of fuels, this dissertation had the objective of studying the activity and the selectivity of cobalt supported on niobium oxide (Co/Nb2O5) for the synthesis reaction of Fischer-Tropsch in slurry reactor. The following variables were evaluated: cobalt loading, reaction temperature, reaction pressure and H2/CO ratio of the syngas. The catalysts were prepared by the precipitation method and characterized by atomic absorption spectroscopy, BET surface area, particle size analysis and temperature programmed CO desorption (TPD-CO). The increase of temperature favored the increase of the activity of the catalyst. The catalyst 10%Co/Nb2O5, at 250ºC and 20 bar, obtained a maximum of production of heavy hydrocarbons (73%) allied with a high activity (XCO=65%). The reduction of the pressure from 20 to 10 bar caused a reduction in the activity of the catalyst, but did not influenced the distribution of products. The composition of the syngas had great influence in the activity, selectivity, and lower H2/CO ratio resulted on a high selectivity to heavy hydrocarbons.