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AssigneeAmax Inc.
InventorsHarry W. Meyer, deceased, Jerry D. Baker, William H. Ceckler
Estimating the term…
A continuous process for producing a substantially dense pelletized metallic molybdenum product from an agglomerated molybdenum trioxide containing feed material in which the feed material is continuously charged at a controlled rate into a reactor formed with a first reaction maintained at a controlled first temperature and containing a first hydrogen-containing atmosphere having a controlled composition for effecting the exothermic reduction of molybdenum trioxide to molybdenum dioxide, whereafter the partially reduced pelletized feed is transferred at a controlled rate into a second reaction zone at a controlled higher temperature and incorporating a second hydrogen-containing atmosphere of a controlled different composition to effect an endothermic reduction of substantially all of the molybdenum dioxide to metallic molybdenum, which upon subsequent cooling is recovered as a pelletized product suitable for use in steelmaking, other metal alloy production, melting, chemical reaction operations and the like. The invention further contemplates a continuous single-stage process for producing a pelletized molybdenum dioxide product from a pelletized molybdenum trioxide feed material and a continuous single-stage process for producing a pelletized substantially metallic molybdenum product from a pelletized molybdenum dioxide feed material.
A continuous process for producing a product in which molybdenum is present in metallic form comprising the steps of agglomerating a particulated feed material composed predominantly of molybdenum trioxide into pellets, continuously introducing said pellets at a controlled rate into a reaction chamber defining a first reaction zone, heating said pellets to a first reaction temperature range of from about 580.degree. C up to about 650.degree. C in the presence of a first reaction gas comprised of an inert carrier gas containing from about 3 mol percent up to about 10 mol percent hydrogen, controlling the flow rate of said first reaction gas and said pellets to provide a stoichiometric excess of hydrogen in an amount greater than 1:1 up to about 10:1 mols hydrogen per mol molybdenum trioxide to effect an exothermic reduction of substantially all of the molybdenum trioxide in said pellets to molybdenum dioxide and to maintain the temperature of said pellets by substantially adiabatic means within said first reaction temperature range, continuously transferring the partially reduced said pellets at a controlled rate from said first reaction zone into a second reaction zone, heating said pellets to a second reaction temperature above about 900.degree. C in the presence of a second reaction gas comprised of an inert carrier gas containing from about 20 mol percent up to about 80 mol percent hydrogen, controlling the flow rate of said reaction gas and said pellets to provide a stoichiometric excess of hydrogen to effect an endothermic reduction of substantially all of the molybdenum dioxide in said pellets to metallic molybdenum and to maintain the temperature thereof above about 900.degree. C, continuously transferring the reduced said pellets at a controlled rate to a third zone containing a protective nonoxidizing atmosphere to effect a stabilization and cooling of said pellets and thereafter recovering the pelletized metallic molybdenum product.
A continuous process for producing molybdenum dioxide comprising the steps of agglomerating a particulated feed material composed predominantly of molybdenum trioxide into pellets, continuously introducing said pellets at a controlled rate into a reaction chamber defining a reaction zone, heating said pellets to a reaction temperature range of from about 580.degree. C up to about 650.degree. C in the presence of a reaction gas comprised of an inert carrier gas containing from about 3 mol percent up to about 10 mol percent hydrogen, controlling the flow rate of said reaction gas and said pellets to provide a stoichiometric excess of hydrogen in an amount greater than 1:1 up to about 10:1 mols hydrogen per mol molybdenum trioxide to effect an exothermic reduction of substantially all of the molybdenum trioxide in said pellets to molybdenum dioxide and to maintain the temperature of said pellets by substantially adiabatic means within said reaction temperature range, continuously transferring the partially reduced said pellets at a controlled rate from said reaction zone to a cooling zone containing a protective nonoxidizing atmosphere to effect a stabilization and cooling of said pellets and thereafter recovering the pelletized molybdenum dioxide product.
Dependencies are inferred from the claim text.