Appeal 2006-2675
Application 10/278,143
(Van Brugge 5:42-44). Van Brugge further suggests that it is, in some
instances, desired to add a trace amount of sulfur to the catalyst to moderate
the activity of hydrogenating metal, i.e., the Group VIII noble metal
(Van Brugge 3:36-39). Therefore, one of ordinary skill in the art would
have added amounts of sulfur necessary to achieve the stated moderation.
Such values, prima facie, would include concentrations within the claimed
range of at least about 0.05 wt%.
Appellants rely upon Biswas as showing that the “trace amount” of
Van Brugge is an amount lower than that required by claim 1. Specifically,
according to Appellants, Biswas, near the bottom of page 212, teaches that at
low S coverage (θ < 0.2), the strong chemical bond of sulfur modifies the
chemical properties of the Pt surface, but at higher values desired reactions
are prevented to the point of the catalyst becoming chemically inert (Br. 5).
Based on this disclosure in Biswas, Appellants conclude that the “trace
amount” of Van Brugge is clearly quantitified by Biswas as being 0.2 S
atoms per Pt atom or less (Br. 5). Appellants further allege that the smallest
amount of S atoms per Pt atom permitted by the claim is 0.34 S atoms per Pt
atom (Br. 5). The implication according to Appellants’ argument is that
because 0.34 S atoms per Pt atom is more than the 0.2 S atoms per Pt atom
disclosed in Biswas, the amounts suggested by “trace amount” as used in
Van Brugge are less than the claimed range.
We do not find Appellants’ evidence and argument persuasive.
Van Brugge is directed to an alkylation process in which paraffins such as
isobutene are reacted with olefins such as 2-butene. Van Brugge is
concerned with moderating the activity of a Group VIII noble metal within a
beta zeolite catalyst. Biswas is directed to reforming catalysts. We
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