Apparatus for producing high yields of carbon nanostructures

Abstract

An apparatus for producing high yields of carbon nanostructures is disclosed. The apparatus includes an electric arc furnace and a feeder that directs solid carbon dioxide into an electrical arc generated by the electric arc furnace. Carbon nanostructures are produced within the electrical arc without producing magnesium oxide (MgO).

What is claimed is: 
     
         1 . An apparatus for producing high yields of carbon nanostructures without forming magnesium oxide (MgO) comprising:
 an electric arc furnace; and   a feeder that directs solid carbon dioxide into an electrical arc generated by the electric arc furnace.   
     
     
         2 . The apparatus of  claim 1  wherein the electric arc furnace has an arc gap between about around 1 centimeter (cm) and around about 10 cm. 
     
     
         3 . The apparatus of  claim 1  wherein the electric arc furnace has an arc gap between around about 10 cm and around about 20 cm. 
     
     
         4 . The apparatus of  claim 1  wherein the electric arc furnace has an arc gap between around about 20 cm and around about 100 cm. 
     
     
         5 . The apparatus of  claim 1  wherein the electric arc furnace has an arc gap greater than around about 100 cm. 
     
     
         6 . The apparatus of  claim 1  wherein the electric arc furnace is configured to generate an electrical arc on the order of tens of amperes. 
     
     
         7 . The apparatus of  claim 1  wherein the electric arc furnace is configured to generate an electrical arc on the order of hundreds of amperes. 
     
     
         8 . The apparatus of  claim 1  wherein the electric arc furnace is configured to generate an electrical arc on the order of thousands of amperes. 
     
     
         9 . The apparatus of  claim 1  further including a graphite electrode that has a diameter that is between around about 100 mm to around about 800 mm. 
     
     
         10 . The apparatus of  claim 1  wherein the feeder is sized to feed solid carbon dioxide blocks. 
     
     
         11 . The apparatus of  claim 1  wherein the feeder is a conduit for conveying solid carbon dioxide pellets into the electrical arc generated by the electric arc furnace. 
     
     
         12 . The apparatus of  claim 1  further including a drive mechanism that urges solid carbon dioxide through the feeder. 
     
     
         13 . The apparatus of  claim 12  further including a control system for controlling the drive mechanism. 
     
     
         14 . The apparatus of  claim 13  wherein the control system is programmable to adjust a solid carbon dioxide feed rate via the drive mechanism to maximize a synthesis rate of carbon nanostructures. 
     
     
         15 . The apparatus of  claim 13  wherein the control system is programmable to adjust a solid carbon dioxide feed rate via the drive mechanism. 
     
     
         16 . The apparatus of  claim 15  wherein the control system is programmable to adjust the solid carbon dioxide feed rate to favor the production of carbon nanotubes over other nanostructures by a predetermined ratio without producing MgO. 
     
     
         17 . The apparatus of  claim 15  wherein the control system is programmable to adjust the solid carbon dioxide feed rate to favor the production of graphene over other nanostructures by a predetermined ratio without producing MgO. 
     
     
         18 . The apparatus of  claim 1  further including a pressure vessel that is configured to hold a regulated pressure environment around the electrical arc generated by the electric arc furnace. 
     
     
         19 . The apparatus of  claim 18  further including a gas source configured to hold gases other than carbon dioxide. 
     
     
         20 . The apparatus of  claim 19  further including a gas valve that is usable to control a flow of gas into the pressure vessel from the gas source.