Appeal No. 1999-2548
Application No. 08/648,236
The subject matter on appeal relates to a process which
includes the step of contacting a regenerated catalyst with a
reducing gas under conditions suitable for countering effects
of contaminating metals thereon. This appealed subject matter
is adequately illustrated by independent claims 1 and 35 which
read as follows:
1. In a process for the catalytic cracking of a
hydrocarbon feed wherein said feed is contacted with a
crystalline zeolite aluminosilicate cracking catalyst
containing antimony and at least one contaminating metal
selected from the group consisting of nickel, vanadium, and
iron under cracking conditions and at least a portion of said
cracking catalyst is periodically regenerated by contact with
a combustion supporting gas under regeneration conditions and
at least a portion of the regenerated catalyst is employed in
the catalytic cracking of hydrocarbon feed, the improvement
consisting essentially of contacting at least a portion of
said regenerated catalyst with a reducing gas under conditions
suitable for countering effects of contaminating metals
thereon to produce a passivated catalyst and employing at
least a portion of said [reduced] passivated catalyst in
cracking said hydrocarbon feed.
35. A process for the cracking of a hydrocarbon feedstock
comprising contacting said feedstock under cracking conditions
in a cracking zone with a cracking catalyst prepared by (1)
starting with a contaminated cracking catalyst comprising
crystalline zeolite alumino-silicate containing at least one
metal selected from the group consisting of antimony, tin,
bismuth, and manganese wherein said contaminants comprise
carbon and at least one metal contaminant selected from the
group consisting of nickel, vanadium, and iron, (2) exposing
said contaminated cracking catalyst in an oxidation step to a
combustion-supporting gas under conditions sufficient to
result in combustion of carbon contaminant, and (3) then
exposing the resulting catalyst in a reduction step to a
2
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 Next
Last modified: November 3, 2007