Appeal No. 1996-3674
Application No. 08/451,826
Here, the specification makes clear that appellants’ invention is directed to “an improvement in
... [zeolite catalysts useful for the production of methylamines] whereby they are blended with one or
more microparticulate binders during formation, which renders the catalyst particles attrition resistant
and therefore suitable for use in fluidized bed reactor processes” (page 1, lines 13-17). Moreover, “for
a catalyst to be considered attrition resistant, the attrition ratio (AR) should be less than or equal to2
about 3" (specification, page 15, lines 12-14). Thus, in this case, the words “attrition resistant,” as
specifically defined in the specification, are essential to point out the invention defined by the claims, i.e.,
they breathe life and meaning to the claims. Therefore, in this case, the preamble does limit the scope
of the claims to a process for producing a defined “attrition resistant” catalyst composition. Thus, it
follows that the examiner has failed to address all of the claim limitations. In short, the examiner has not
pointed out and we do not find where Bergna, Abrams, Beck or THE CONDENSED CHEMICAL
DICTIONARY disclose or suggest a process of producing a catalyst having an attrition ratio less than
2As set forth in the paragraph bridging pages 14-15 of the specification,
Attrition measurements are performed using an attrition mill which simulates particle
attrition near the gas spargers of a fluidized bed. A catalyst charge is loaded into a column fitted
with a single 0.016" perforation. Air flows through the perforation, fluidizes the catalyst bed, and
causes attrition. For most measurements, the constant air flow through the mill is calibrated to
yield a linear velocity of 760 ft/s through the orifice; this compares to a typical velocity of 150 ft/s
in a commercial fuel spargers. The attrition mill measurement accelerates attrition by a factor of
roughly thirty. A 24 hour attrition measurement is a reliable indicator of attrition in a commercial
reactor. Attrited fines (i.e., those particles lower than 20 micrometers in diameter) are collected in
an overhead flask which is fitted with a porous thimble. Flask weight, recorded as a function of
time, is used to calculate attrition. The determination of attrition is calculated as an attrition ratio,
AR: catalyst attrition divided by the attrition rate of a fluid cracking catalyst standard (FCC). The
FCC standard is supplied by Davison Chemical, Baltimore Maryland (SMR-5-5209-0293).
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