New Catalysts from Spent Catalysts - Spent Hydroprocessing Catalysts - page 249

Table 9.7: Composition of spent-decoked catalysts [From ref. 551 . Reprinted with permission].

Metal (wt.%) Catalyst A Catalyst B Catalyst C

Mo 10 . 0 7 . 7 9 . 7

Ni

< 0 . 01

3 . 3 2 . 9

Co 2 . 9

< 0 . 01 < 0 . 01

Fe < 0 . 05 0 . 06 0 . 1

V nd 4 . 0 nd

9.4 Preparation of Useful Materials from Spent Catalysts

Detailed accounts of the processes reported in patented or published literature on the use of
spent hydroprocessing catalysts in the preparation of various types of catalysts and other
valuable materials except the recovery of metals and metal compounds were given by Marafi
and Stanislaus [22] . Table 9.9 lists useful materials prepared from spent hydroprocessing
catalysts and their industrial application. Utilization of spent catalysts as raw materials in the
production of a wide range of commercial products is an attractive option for their recycling
from both environmental and economic points of view. In this regard, construction materials,
e.g., cement, concrete, etc., water treatment applications, abrasive materials and synthetic
aggregates have been receiving attention.

9.4.1 Utilization in Cement Industry

Although this outlet is dominated by spent fluid catalytic cracking (FCC) catalysts, after
certain pretreatments, spent hydroprocessing catalyst may be suitable as well as long as the

Figure 9.11: Breakthrough curves for catalyst A and catalyst C [From ref. 551 . Reprinted with
permission].