Appeal No. 94-2410
Application 08/011,573
crystalline aluminosilicate zeolite having an alpha value below
about 10 (brief, pages 2-6).
Chloupek discloses a process for disproportionating
paraffinic hydrocarbons with an acidic, crystalline
aluminosilicate catalyst (abstract). The catalyst is described
as “highly acidic” (column 1, lines 10-11, and column 2, lines 5-
6), but the alpha value is never mentioned.
Morrison discloses a process for disproportionating propane
by contact with a catalyst comprising a crystalline zeolite
having a silica-to-alumina ratio of at least 12, a Constraint
Index of 1 to 12 (column 1, lines 47-53), and a high acid
activity as measured by a high alpha value (see the “alpha test”
at column 6, lines 11-21). No specific alpha values are
disclosed by the Morrison reference.
Harandi, which incorporates Morrison by reference (see
column 1, lines 66-67), discloses two disproportionation
reactions, one for propane and one for butane. Both reactions
use medium pore zeolite catalysts (column 3, lines 27-36) with
the same silica-to-alumina and Constraint Index limitations as
taught by Morrison. There is no disclosure of alpha values.
It is well settled that the examiner bears the initial
burden of presenting a prima facie case of obviousness based on
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