New Developments in Deep Hydroconversion of Heavy Oil Residues with Dispersed Catalysts. 1. Effect of Metals and Experimental Conditions

A comparative study of the effect of experimental conditions on the deep hydroconversion (up to 90 %) of an heavy oil residue (Safaniya) in the presence of dispersed catalysts is reported. Severe thermal conditions are required to obtain a high conversion level. With molybdenum naphthenate as catalyst precursor, a low metal concentration (0.02 wt %) and a moderate hydrogen pressure level (7.5 MPa at cold) are efficient to maintain a low coke yield (2 wt %). In contrast to molybdenum naphthenate, a higher amount of phosphomolybdic acid is needed to achieve the same result. The reason for its weaker catalytic activity was attributed to a lower sulfidation state of the Mo catalyst, as outlined by physical characterization of the catalyst (XRD, HREM, STEM-EDX).