Appeal No. 96-0216
Application 07/842,915
such as caustic soda and caustic potash, and an active carbon,
are heated in a sealed container at 150E-220EC (392E-410EF) and
10-20 kg/cm pressure. Nakagawa, p. 2, first complete para.
Blardone, discloses a process for extracting silica from the
hulls of grains. Blardone col. 1, lines 10-14. Blardone
describes the boiling of burned rice hulls in a solution of water
and sodium hydroxide for several hours, followed by filtration.
Id, col. 1, lines 38-45. The mass remaining in the filter is
washed with water and the filtrate concentrated, to the extent
desired, by boiling. Id., sentence bridging col. 1-2. Mallow
discloses a method of making a solidified silica foam product
from sodium silicate, potassium silicate, or mixtures thereof.
Mallow, col. 1, lines 10-14.
The examiner has primarily based his conclusion of
obviousness on the teachings of Nakagawa and Blardone. According
to the examiner,
[i]t would have been obvious to one having ordinary skill in
the art to employ ash as a source of raw siliceous material
for the advantages of low price and availability as a waste
product of the rice industry. Applicants’ limitation of the
upper temperature limit and pressure would have been obvious
to one having ordinary skill in the art. This is evidenced
by applicants’ statement (page 10, lines 30-33 of the
instant specification) that by simple experiments optimum
temperature and pressures can be determined. It would have
been within the purview of the ordinary artisan to optimize
the temperature and pressure of the kinetics of dissolution
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