Appeal No. 2003-0366
Application 09/349,759
material on the zeolite catalyst and then an aqueous solution of a dealuminizing agent, such as an
acid, is applied to the silylated zeolite catalyst (cols. 3-4). Beck theorizes that such treatments,
inter alia, render “acid sites on the external surfaces of the zeolite substantially inaccessible to
reactants” (col. 10, lines 37-54). Beck would have further disclosed that “[t]he ‘alpha value’ of a
catalyst is an approximate indication of its catalytic cracking activity,” which value “may be
increased by mild steaming” (col. 10, line 55, to col. 11, line 5). Beck exemplifies the use of,
inter alia, ZSM-5 zeolites and teaches that the zeolite catalysts can be used, inter alia, “in the
conversion of light paraffins and olefins to aromatic compounds” as exemplified by the
Cattanach references (e.g., cols. 5-7 and 12-16, col. 14, lines 37-41, and the Examples). The
Cattanach references also would have disclosed the use of ZSM-5 zeolites as catalysts for the
same conversion methods.
Based on this substantial evidence in the references, we agree with the examiner’s
position because we find on this record that, prima facie, Beck would have provided the
motivation to one of ordinary skill in this art to prepare similar zeolite catalysts to those disclosed
in the reference using the same steps taught in the reference, albeit in different order, in the
reasonable expectation of obtaining similar zeolite catalysts having similar properties that are
useful in the same methods, thus enabling the preparation of such zeolites and their use. Indeed,
on this record, we determine that, prima facie, one of ordinary skill in this art, armed with the
knowledge in the art that zeolite catalysts can be beneficially modified with respect to aluminum
and silicon, would have reasonably expected that the silylation step, the acid dealumination step
and the steam treatment step taught by Beck would each function in similar manner to provide a
zeolite catalyst, such as a ZSM-5, with a similar structure with respect to the availability of acid
sites on the external surfaces thereof and an increased “alpha value,” thus providing similar
properties for use in the same methods, regardless of the order in which the steps are employed.
Consequently, we are of the opinion that one of ordinary skill in this art routinely working within
the teachings of Beck would have reversed the treatment steps shown in the reference and would
have used the resulting zeolite catalyst in the methods of the Cattanach references incorporated
by Beck, thus reasonably arriving at the claimed methods encompassed by appealed claims 15
and 36 without recourse to appellants’ specification. Compare In re Dillon, 919 F.2d 688, 692-
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