Appeal No. 96-0112
Application 07/877,913
are all of the claims pending in the application.
Claim 1 is representative of the subject matter on appeal and reads as follows:
1. In a catalytic cracking process wherein a feed comprising non-distillable hydrocarbons is
catalytically cracked in a riser reaction zone, operating at riser cracking conditions, including a riser
vapor residence time, by contact with a source of hot, regenerated cracking catalyst to produce
catalytically cracked vapors and spent cracking catalyst, cracked vapors are withdrawn as products,
and spent cracking catalyst is regenerated in a catalyst regeneration means to produce hot regenerated
cracking catalyst which is recycled to contact said feed, the improvement comprising:
cracking in the base of a vertical riser reactor having a length, for at least 1 second of vapor
residence time and for at least the first 50 % of the length of the riser reactor from the base, a heavy
feed containing at least 10 wt% non-distillable hydrocarbons by contact with hot regenerated cracking
catalyst at a cat:feed weight ratio of a least 4:1 and wherein the amount and temperature of the hot
regenerated catalyst are sufficient to produce a catalyst/feed mixture temperature sufficient to promote
both catalytic cracking and undesired thermal cracking of said feed in said riser; and
quenching, after at least 1.5 seconds of vapor residence time, said catalyst mixture in a quench
zone within said riser within the first 80% of the length of the riser reactor from the base, [sic, with] an
inert quench fluid in an amount sufficient to quench the temperature in the riser at least 5 F.o
The sole reference relied on by the examiner is:
Owen 5,073,249 Dec. 17, 1991
(Filed Nov. 21, 1989)
The appealed claims stand rejected under 35 U.S.C. § 103 as unpatentable over the disclosure
of Owen.
We have carefully reviewed the entire record before us, including all of the arguments advanced
by appellants and the examiner in support of their respective positions. This review leads us to
conclude that only the examiner’s § 103 rejection of claims 1 through 7, 9 through 15 and 18 is well-
2
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