Appeal No. 2002-1863
Application No. 09/206,207
an olefin-containing feedstock containing at least 100 parts per
million (ppm) of an impurity selected from the group consisting of
nitrogen, sulfur and oxygen using a pretreated MFI crystalline
catalyst under particular cracking conditions (Brief, page 3). The
invention may be further understood by illustrative independent
claim 1, reproduced below:
1. A process for the catalytic cracking of at least one
olefin in an olefinic stream containing impurities, the cracking
process being selective towards light olefins in the effluent, the
process comprising contacting at an inlet temperature of from 500
to 600/C a feedstock olefinic stream containing at least 100 ppm
of at least one impurity selected from the group consisting of
nitrogen, sulphur and oxygen with a MFI crystalline silicate
catalyst, the catalyst having been heated in steam to reduce the
tetrahedral aluminum in the crystalline silicate framework and
subjected to an aluminum extraction process to remove aluminum from
the pores of the crystalline silicate after which the catalyst has
a silicon/aluminum atomic ratio of from 180 to 1000, to produce an
effluent stream having substantially the same olefinic content by
weight as, but a different olefin distribution than, the feedstock
contains.
The examiner relies upon the following references as evidence
of obviousness:
Eberly, Jr., et al. (Eberly) 3,506,400 Apr. 14, 1970
Glockner et al. (Glockner) 4,078,011 Mar. 07, 1978
Colombo et al. (EP ‘060) 0 109 060 May 23, 1984
(published European Patent Application)
Claims 1, 2, 6-9, 12, 13, 15, 17-19 and 27 stand rejected
under 35 U.S.C. § 103(a) as unpatentable over EP ‘060 in view of
Eberly (Answer, page 3). Claims 16 and 20-26 stand rejected under
2
Page: Previous 1 2 3 4 5 6 7 8 9 10 Next
Last modified: November 3, 2007