Appeal No. 1998-0558
Application No. 08/564,942
invention as an improvement over the C alkyl aromatic
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hydrocarbon isomerization disclosed by Riehm (page 3 of
specification, lines 19-24) "by limiting the temperature of
the reduction step in the activation of the catalyst to no
more than 340 degrees celsius" to attain reduced xylene ring
loss during the process (page 3 of the specification, lines
13-15). Accordingly, appellant does not dispute the
examiner's factual determination that Riehm, Berger and the
admitted prior art teach a process for isomerizing C alkyl-
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aromatic hydrocarbons by contact with a hydrogenation-
dehydrogenation catalyst comprising a Group VIII metal such as
palladium or platinum in the presence of hydrogen, as well as
separating the effluent from the reactor to hydrogen-rich and
hydrocarbon-rich fractions and recycling an
aromatic-rich fraction back to the isomerization zone.
While the examiner recognizes that Riehm, Berger and the
admitted prior art do not disclose appellant's activation of
the catalyst
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