Process of making niobium oxide

A process for the preparation of metal oxides wherein the metal for forming said oxide is contained in an alloy selected from the group consisting of ferro alloy and nickel alloys comprising the steps of:

• a) providing a ferrometal or nickel metal alloy for use in the process,
• b) contacting the ferrometal or nickel metal alloy with a hydrogen-containing gas,
• c) reacting the alloy provided with the hydrogen initially at ambient temperature and at about 3 psig to about 15 psig of hydrogen gas, to form a hydride product,
• d) subdividing the hydrided product into particle sizes suitable for reaction with a nitrogen-containing gas,
• e) nitriding the hydride product by contacting the subdivided hydride product with a nitrogen-containing gas at a temperature above about 500.degree. C., for a sufficient period of time to substantially completely react the nitrogen-containing gas with the hydride product to form nitrides of the alloy constituents,
• f) subsequent to nitride formation in the nitriding reaction, contacting the nitrides produced with an aqueous acid leach solution for a sufficient period of time to dissolve the metal nitride formed during the nitriding in the leach solution, and
• g) separating the acid soluble nitrides in the leach solution from the acid insoluble nitrides, and
• h) reacting the acid soluble nitrides with oxygen at a sufficiently elevated temperature and for a sufficient period of time to form the metal oxide of the acid insoluble metal nitride.