Appeal No. 1997-0448
Application No. 08/327,980
about 150E C to form soluble and insoluble molybdenum species, solubilizing the insoluble molybdenum
species by alkaline digestion, separating the soluble molybdenum species from any residual insoluble
contaminants, extracting the molybdenum species from the aqueous media with an organic solvent, and
recovering the molybdenum values from the organic solvent as molybdenum trioxide (brief, pages 3-4;
abstract). According to the specification, this process allows a greater recovery of higher purity
molybdenum trioxide from low grade molybdenum concentrates containing greater than 5 wt % copper
or greater than 10 wt % of naturally floatable gangue materials, e.g., talc and sericite, than can be
recovered from conventional techniques, e.g., roasting (para. bridging pages 9-10).
OPINION
I. Rejection of claims 1-7 and 10-19 as obvious over Barry in view of Vertes and Chiola
Barry describes a process of producing molybdenum trioxide from a molybdenite concentrate
typically comprising in excess of about 80% molybdenum sulfite, about 5 to about 10% silica and less
than 1% of contaminating metals, e.g., copper, comprising (A) pressure oxidizing an aqueous slurry of3
particulate concentrate at a partial pressure of free oxygen above about 50 psi, preferably from about
300 psi to about 600 psi, and at a temperature of at least about 100E C, preferably from about 150E C
to about 250EC, to substantially convert the molybdenum disulfide to the corresponding oxide; (B) 4
3See Barry, col. 2, lines 22-26 and 52-58.
4See Barry, col. 1, lines 52-70; col. 3, lines 65-68; col. 4, lines 6-40.
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