EFFECTS OF CATALYST COMPOSITION AND PRETREATMENT ON THE PRODUCT DISTRIBUTION IN HYDRODESULPHURIZATION, HYDRODENITROGENATION AND HYDRODECHLORINATION

摘要

In a number of cases, the distribution of intermediates or products in consecutive and parallel schemes of hydrorefining reactions over transition metal sulphides across the Periodic Table is quite different from the distribution over conventional Co-Mo, Ni-Mo and Ni-W systems. The number of saturated nonaromatic heterocycles, desorbed during HDS and HDN of aromatic heterocycles, can be varied over a broad range by combining the effects of catalyst type, hydrogen and hydrogen sulphide partial pressures and temperature. Depending on the catalyst and kinetic conditions, HDN can be slower or faster than HDS, and HDC can be faster or slower than HDS. Type of support, active phase loading and details of catalyst pretreatment usually seem to be of secondary importance for the distribution of intermediates in consecutive schemes and for the distribution of products in parallel schemes, when compared with the effect of type of transition metal in the active phase and with the effects of hydrogen pressure, temperature and hydrogen sulphide partial pressure.