Appeal No. 1997-1793
Application No. 08/528,044
calcining the dried precipitate in air at 500EC for 2-3 hours
(experimental
section, page 3208). However, as in the appellants’ flame
hydrolysis preparation process (specification, page 1, line 31
to page 2, line 7; appealed claim 3), Hattori describes the
coprecipitation method as reacting an iron salt with titanium
tetrachloride and then treating the resulting product at
elevated temperatures to yield an iron oxide-titanium oxide
binary oxides having the same composition and the same surface
area as recited in appealed claim 2. In this regard, we note
that the appellants have contested the examiner’s rejection as
follows:
One of the critical features of the present
invention is that the iron oxide/titanium dioxide
mixed oxide is flame hydrolytically prepared. This
feature is believed to be critical to the invention
because flame hydrolysis enables production of
titanium dioxide having very small particle size,
i.e., a BET surface area of 10-150 m /g, as2
positively recited in claim 2. Such particles are
advantageous because they have no pores, or very few
pores which can be clogged with so-called secondary
particles. [Underscoring original, italics added;
brief, page 4.]
Although Hattori uses a different preparation method, the
final catalyst product identified as “Fe O -TiO (1/9)”
2 3 2
possesses the same composition and the same surface area as
the “flame hydrolytically prepared” product recited in
appealed claim 2. Under these circumstances, we think it is
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