Process for manufacturing metal powders

Abstract

A process of producing metal powders by feeding a metal oxide and a reducing agent into a rotary reactor to form a mechanical fluid bed. The fluid bed is rotated with a rotation speed of about 100 rpm. The fluid bed is then heated to a reaction temperature of up to 1200° C. The pressure is then set within the rotary reactor to a pressure in a range of 0.001 bars to 2.0 bars, as a result reducing the reaction temperature to a temperature in a range of 600° C. to 1200° C. Finally, the pressure and the rotation are maintained, wherein a high value metal powder is formed without the requirement for post-grinding process steps. A product resulting from specific settings of the process include a high value molybdenum powder capable of being used as a chemical catalyst and other specialty applications specific to the metal, eliminating costly production methods.

I claim: 
     
         1 . A process of producing a metal powder, comprising the steps of:
 feeding a metal oxide and a reducing agent into a rotary reactor to form a mechanical fluid bed;   rotating said mechanical fluid bed with a rotation speed of about 100 rpm;   heating said mechanical fluid bed to a reaction temperature of up to 1200° C.;   setting pressure within said rotary reactor to a pressure in a range of 0.001 bars to 2.0 bars, as a result reducing said reaction temperature to a temperature in a range of 600° C. to 1200° C.; and,   maintaining said pressure and said rotation to form said metal powder.   
     
     
         2 . The process of  claim 1 , wherein prior to the step of feeding, said metal oxide is discharged to a grinding mill. 
     
     
         3 . The process of  claim 1 , wherein said reducing agent is selected from the group consisting of coal, hydrogen, natural gas, ammonia, carbon powder, nitrogen, and synthetic gas. 
     
     
         4 . The process of  claim 1 , further comprising the step of cooling said metal powder to below 60° C. 
     
     
         5 . The process of  claim 1 , wherein particles of said metal powder have a particle size in a same range of said metal oxide. 
     
     
         6 . The process of  claim 5 , wherein at least 95% of said metal powder has said particle size in the same range as said metal oxide. 
     
     
         7 . The process of  claim 1 , wherein said metal powder has a purity greater than or equal to metal content of said metal oxide. 
     
     
         8 . The process of  claim 1 , further comprising the step of injecting a process gas into said mechanical fluid bed to form an off-gas. 
     
     
         9 . The process of  claim 8 , further comprising the step of processing said off-gas through a thermal oxidizer. 
     
     
         10 . The process of  claim 8 , wherein said process gas is selected from the group consisting of ammonia, ammonia doped with oxygen, hydrogen, and natural gas. 
     
     
         11 . The process of  claim 8 , further comprising the step of treating said off-gas to retain CO 2  and H 2 O, leaving in a stream of only N 2 , a small amount of H 2 , and traces of CO, as a result producing a gas blanket. 
     
     
         12 . The process of  claim 11 , further comprising the step of injecting said gas blanket into said mechanical fluid bed to prevent re-oxidation of said metal powder. 
     
     
         13 . The process of  claim 1 , wherein said metal oxide is a fine from an ore of said metal powder. 
     
     
         14 . The process of  claim 1 , wherein greater than 99% of said metal oxide is converted to said metal powder. 
     
     
         13 . A product produced from a process comprising the steps of:
 feeding the metal oxide and a reducing agent into a rotary reactor to form a mechanical fluid bed;   rotating said mechanical fluid bed with a rotation speed of about 100 rpm;   heating said mechanical fluid bed to a reaction temperature in the range of 600° C.-1200° C. while maintaining a pressure within said rotary reactor in the range of 0.001 bar to 2 bar;   maintaining said pressure and said rotation, wherein said product is a high-purity metal oxide powder.   
     
     
         14 . The product of  claim 13 , wherein further reduction of said high-purity metal oxide powder occurs while particle size distribution of said high-purity iron oxide powder is maintained even when the chemistry of the particle changes by injecting a reductant into said rotary reactor. 
     
     
         15 . The product of  claim 13 , wherein re-oxidation of said high-purity metal oxide powder is prevented by flying ammonia into said rotary reactor, thereby producing N 2  and H 2  to act as a secondary reducing agent for said mechanical fluid bed. 
     
     
         16 . The product of  claim 1 , wherein said secondary reducing agent is maintained until a temperature of said product reaches 60° C., after which said product is sorted and processed for utilization. 
     
     
         17 . The product of  claim 13 , wherein further reduction of said high-purity metal oxide powder results by flying ammonia into said rotary reactor, and concurrently by flowing natural gas into said rotary reactor. 
     
     
         18 . A product produced from a process comprising the steps of:
 feeding MoO 3  and a blend of H 2  and N 2  into a rotary reactor to form a mechanical fluid bed;   rotating said mechanical fluid bed with a rotation speed of about 100 rpm;   heating said mechanical fluid bed to a reaction temperature in the range of 620° C.-640° C. while maintaining a pressure within said rotary reactor of up to 1 bar;   maintaining said pressure and said rotation, wherein said product is a high-purity molybdenum powder.   
     
     
         19 . The product of  claim 18 , wherein for the step of feeding, said MoO 3  and said blend are flown through said rotary reactor at a rate of 18.4 Nm 3 /hour per 1000 kg of MoO 3 . 
     
     
         20 . The product of  claim 18 , wherein said MoO 3  and said blend of H 2  and N 2  are loaded in a quantity equal to 316 Nm 3  of H 2  and 790 Nm 3  of N 2  for every 1000 kg of MoO 3 .