Environmental Engineering Reference
In-Depth Information
Table 9.8: Breakthrough times for spent-decoked catalysts and zinc ferrite [From ref.
551
.
Reprinted with permission].
Breakthrough time (min)
A
A
a
Catalyst A
at 530 K
90
101
at 630 K
105
118
Catalyst B
at 530 K
33
77
at 630 K
24
56
Catalyst C
at 630 K
47
149
Zinc ferrite
at 530 K
170
170
at 630 K
180
180
a
Normalized to the same amount of active metals.
content of contaminants is not too high. The use of FCC catalysts in cement and concrete
production has been reported in many studies
[22,552-554]
. These catalysts contain mainly
SiO
2
and Al
2
O
3
together with some minor impurities. Studies have shown that up to 6% of
spent FCC catalysts can be mixed with other raw materials (75% lime stone and 19% clay) for
Portland cement production. In the cement Kiln at high temperature SiO
2
and Al
2
O
3
react with
lime to produce Portland cement.
Extensive studies have been conducted in recent years on utilization of spent FCC catalysts in
the production of cement mortars for concrete
[22,555,556]
. The results in general showed that
the spent catalyst could be used as a substitute for sand as well as source of ultra fine material
Table 9.9: Useful materials prepared from spent hydroprocessing catalysts [From ref.
22
. Reprinted
with permission].
Material produced
Industrial applications
Fused alumina with corrundum
crystallite structure
Abrasive material; refractory material
Fused aluminium oxide
Ceramic and refractory industries
Anorthite glass ceramics
Electrical insulating material in electronic industry
Synthetic aggregates
Construction industry; cement concrete
Refractory cement/refractory brick
Refractory material for high temperature furnace
