EFFECT OF FLUORINE IN THE SYNERGISM Co-Mo VIA HYDROGEN SPILLOVER ON THE HYDRODESUL-PHURIZATION OF REFRACTORY MOLECULES

ABSTRACT The influence of fluorine concentration on the synergism between Co/γ-Al 2 O 3 and Mo/γ-Al 2 O 3 stacked beds separated by 3-mm of γ-Al 2 O 3 F x (x = 0 - 2.5%), in the hydrodesulphurization of refractory molecules contained in gasoil, under operating conditions similar to those of industry, was studied. The results shown, that the synergism increases with F content, reaching a maximum at 0.8% of fluorine, which it is related to changes in zero point of charge (ZPC) and acid strength, due to the incorporation of fluorine. The conversion of most refractory molecule reported is favoured by fluorine. Keywords: Hydrodesulphurization, Fluorine, Stacked Bed, Synergism. 1. INTRODUCTION At the present, environmental regulations are becoming more stringent in relation to maximum levels of sulphur allowed in diesel, increasing the inter-est in more efficient systems, in order to obtain fuels that meet the standards. This, coupled with the need to exploit petroleum fractions which have a greater amount of refractory sulphur compounds, and the use of products derived from petroleum that will remain the main energy source, have renewed efforts to develop new catalysts for hydrodesulphurization (HDS)