Catalyst and process to produce nanocarbon materials in high yield and at high selectivity at reduced reaction temperatures

Abstract

A carbon nanofiber system is synthesized with very high purity (above 95%), selectivity of the carbon morphology, and exceptionally high yield. A custom made catalyst with a particle size of ≦10 nm and a high surface area (>50 m 2 /g), provides a higher morphological selectivity and higher yield. The reactivity of these catalyst particles is maintained even after 24 hours reaction such that yield exceeds 200 g carbon per gram of catalyst. The catalysts which are key to the products and yields achieved are prepared to specific parameters (size distribution, composition and crystallinity) specified and via a flame synthesis process as taught in U.S. Pat. No. 6,132,653.

1 . A process for producing nanocarbon materials, comprising the following steps: 
 a. providing a catalyst with a particle size of ≦10 nm and a surface area greater than 50 m2/g;    b. reacting carbonaceous feedstocks in the presence of the catalyst over a given period of time to produce carbon nanofibers with over 99% purity and a morphological selectivity approaching 100% in yields ≧140 g carbon/g catalyst with higher reactivity.    
     
     
         2 . The process in  claim 1 , wherein the catalyst is a metal oxide catalyst selected from the metals including iron, nickel, cobalt, lanthanum, gold, silver, molybdenum, iron-nickel, iron-copper and their alloys.  
     
     
         3 . The process in  claim 1 , wherein the catalyst is prepared to specific parameters (size distribution, composition and crystallinity) specified and via a flame synthesis process.  
     
     
         4 . The catalyst in  claim 1 , wherein the catalyst possesses a single crystal morphology.  
     
     
         5 . The process in  claim 1 , wherein the yield of carbon nanomaterial resulted in ≧140 g carbon per g/catalyst.  
     
     
         6 . The process in  claim 1 , wherein the morphology of the carbon micro structure can be selectively controlled to achieve various desired orientations in selectivities of ≧90%.  
     
     
         7 . A process for producing nanocarbon materials, comprising the following steps: 
 a. providing a metal oxide catalyst with a particle size of about ≦10 nm and a surface area greater than 50 m2/g;    b. reacting carbonaceous feedstocks in the presence of the catalyst over a given period of time to produce carbon nanofibers with over 99% purity and a morphological selectivity approaching 100% with yield ≧140 g carbon/g catalyst.    
     
     
         8 . The process in  claim 7 , wherein the reaction took place at a temperature not exceeding 550 C.  
     
     
         9 . The process in  claim 7 , wherein the purity of carbon nanofibers was >99% after 8 hours reaction time.  
     
     
         10 . The process in  claim 7 , wherein the metal oxide catalyst is selected from a group of metals including iron, nickel, cobalt, lanthanum, gold, silver, molybdenum, iron-nickel, iron-copper and their alloys.  
     
     
         11 . Carbon nanofibers of high purity and high reactivity, produced by the steps of: 
 a. providing a metal oxide catalyst with a particle size of ≦10 nm and a surface area greater than 50 m2/g;    b. reacting carbonaceous feedstocks in the presence of the catalyst over a given period of time to produce the carbon nanofibers with over 99% purity and a selectivity approaching 100% with higher reactivity.    
     
     
         12 . The carbon nanofibers produced by the process in  claim 11 , wherein the metal oxide catalyst is selected from a group of metals including iron, nickel, cobalt, lanthanum, gold, silver, molybdenum, iron-nickel, iron-copper and their alloys.  
     
     
         13 . The carbon nanofibers produced by the process in claim  11 , wherein the purity of carbon nanofibers was ≧99% in after 8 hours reaction time.  
     
     
         14 . A carbon nanofiber, of the type produced in the presence of an metal oxide catalyst, the carbon nanofiber comprising at least 99% pure carbon, and produced at high yield, and >90% morphological selectivity.  
     
     
         15 . The carbon nanofiber in  claim 14 , wherein the metal oxide catalyst is selected from a group of metals including iron, nickel, cobalt, lanthanum, gold, silver, molybdenum, iron-nickel, iron-copper and their alloys.  
     
     
         16 . A carbon nanofiber composition exhibiting 90% Selectivity to a single morphology as produced.  
     
     
         17 . The composition in  claim 16 , wherein the morphology comprises graphene layers oriented parallel to the fiber axis.  
     
     
         18 . The composition in  claim 16 , wherein the morphology comprises graphene layers oriented perpendicular to the fiber axis.  
     
     
         19 . The composition of  claim 16 , wherein the morphology comprises graphene layers oriented at a specific and equal (±10°) angle to the fiber axis.