Rapid conversion of metal-containing compounds to form metal oxides

Abstract

A method of converting metal-containing compounds into a metal or metal oxide by rapidly heating the metal-containing compound to an elevated temperature to instigate conversion and holding the metal-containing compound at the elevated temperature for a time sufficient to effect formation of the metal or metal oxide is an efficient and economical method of producing metals and metal oxides.

What is claimed is:  
     
         1 . A method for converting a metal-containing compound to form the metal or an oxide of the metal of the metal-containing compound, comprising: 
 heating the metal-containing compound at a rate of between about 100° C./second to about 100,000,000° C./second to an elevated temperature that makes the conversion of the metal-containing compound thermodynamically favorable, and    holding the metal-containing compound at the elevated temperature for a residence time sufficient to convert the metal-containing compound into at least one product selected from the group consisting of (i) the metal and (ii) oxides of the metal.    
     
     
         2 . The method of  claim 1 , wherein the residence time is from about 0.1 to about 60 seconds.  
     
     
         3 . The method of  claim 1 , wherein the conversion is by decomposition.  
     
     
         4 . The method of  claim 1 , wherein the conversion is by oxidation.  
     
     
         5 . The method of  claim 1 , wherein the conversion is by reduction.  
     
     
         6 . The method of  claim 1 , wherein the conversion is by substantially simultaneous decomposition and reduction.  
     
     
         7 . The method of  claim 1 , wherein the conversion is by substantially simultaneous decomposition and oxidation.  
     
     
         8 . The method of  claim 1 , wherein the residence time is from about 0.1 second to 30 seconds.  
     
     
         9 . The method of  claim 1 , wherein the residence time is from about 0.1 second to 10 seconds.  
     
     
         10 . The method of  claim 1 , wherein the heating rate is from about 100 to about 100,000,000° C./second.  
     
     
         11 . The method of  claim 1 , wherein the heating rate is from about 1,000 to about 1,000,000° C./second.  
     
     
         12 . The method of  claim 1 , wherein the heating rate is from about 10,000 to about 100,000° C./second.  
     
     
         13 . A method for converting a metal-containing compound to form the metal or an oxide of the metal of the metal-containing compound, comprising: 
 heating the metal-containing compound at a rate of between about 100° C./second to about 100,000,000° C./second to an elevated temperature that makes the conversion of the metal-containing compound thermodynamically favorable;    holding the metal-containing compound at the elevated temperature for a residence time sufficient to convert a portion of the metal-containing compound into at least one precursor selected from the group consisting of (i) the metal and (ii) oxides of the metal;    heating the precursor to a second elevated temperature that makes the conversion of the precursor thermodynamically favorable; and    holding the precursor at the second elevated temperature to convert substantially all of the precursor into at least one product selected from the group consisting of (i) the metal and (ii) oxides of the metal.    
     
     
         14 . A method for converting a metal-containing compound to form the metal or an oxide of the metal of the metal-containing compound, comprising:. 
 heating the metal-containing compound at a rate of between about 100° C./second to about 100,000,000° C./second to an elevated temperature that makes the conversion of the metal-containing compound thermodynamically favorable;    holding the metal-containing compound at the elevated temperature for a residence time sufficient to convert the metal-containing compound into at least one precursor selected from the group consisting of (i) the metal and (ii) a precursor oxide of the metal;    heating the metal or precursor oxide to a second elevated temperature that makes the conversion of the metal or precursor oxide thermodynamically favorable; and    holding the metal or precursor oxide at the second elevated temperature to convert substantially all of the metal or precursor oxide into the oxide of the metal.    
     
     
         15 . A method for converting a metal-containing compound to form the metal of the metal-containing compound, comprising: 
 heating the metal-containing compound at a rate of between about 100° C./second to about 100,000,000° C./second to an elevated temperature that makes the conversion of the metal-containing compound thermodynamically favorable;    holding the metal-containing compound at the elevated temperature for a residence time sufficient to convert the metal-containing compound into at least one precursor metal-containing compound;    heating the precursor metal-containing compound to a second elevated temperature that makes the conversion of the precursor metal-containing thermodynamically favorable; and    holding the precursor metal-containing compound at the second elevated temperature to convert the precursor metal-containing compound into the metal.    
     
     
         16 . The method of  claim 1 , wherein the metal-containing compound is a metallic oxalate selected from the group consisting of the Group VIII (Ni, Co, Fe), Group IVA (Sn, Pb), Group IVB (Hf), Group VB(Ta), Group VIB (Cr, W), and combinations thereof, and the heating of the metal-containing compound is in a substantially non-oxidizing atmosphere.  
     
     
         17 . The method of  claim 16 , wherein the at least one product is a metal selected from the group consisting of nickel, cobalt, lead and tin.  
     
     
         18 . The method of  claim 17 , wherein the elevated temperature is between approximately 600° C. and 1300° C.  
     
     
         19 . The method of  claim 17 , wherein the residence time is from about 0.1 second to about 30 minutes.  
     
     
         20 . The method of  claim 17 , wherein the residence time is from about 0.1 second to about 30 seconds.  
     
     
         21 . The method of  claim 17 , wherein the residence time is from about 0.1 second to about 10 seconds.