Catalyst Deactivation - Spent Hydroprocessing Catalysts - page 61

Figure 4.9: Deposition of metals and coke along the length of 1st and 2nd reactors for catalysts
in Table 7.1 ; open symbols catalyst A, full symbols catalyst D [From ref. 189 . Reprinted with
permission].
approach those observed during hydroprocessing of VGO. Then, different types of catalysts
may be required for every stage.
Figure 4.9 [189,190] shows the deposition of metals and coke in two trickle-bed reactors
connected in a series, used for hydroprocessing of the deasphalted oil (DAO) containing
27 ppm of V+Ni and less than 1 wt.% of asphaltenes. This DAO was obtained by deasphalting
of the vacuum residue derived from conventional crude. The properties of catalysts A and D
used for this study are shown in Table 4.2 [190] . The catalysts (in baskets) were placed in the