Compositions of matter including solid carbon formed by reducing carbon oxides
A method for production of various morphologies of solid carbon product by reducing carbon oxides with a reducing agent in the presence of a catalyst. The carbon oxides are typically either carbon monoxide or carbon dioxide. The reducing agent is typically either a hydrocarbon gas or hydrogen. The desired morphology of the solid carbon product may be controlled by the specific catalysts, reaction conditions, and optional additives used in the reduction reaction. The resulting solid carbon products have many commercial applications.
1. A composition of matter comprising entangled agglomerations of fibrous carbon on an iron-containing catalyst; wherein the entangled agglomerations of fibrous carbon are clustered with a characteristic dimension of less than 1 millimeter; wherein the fibrous carbon is formed by reacting carbon dioxide with a gaseous reducing agent in the presence of an iron-containing catalyst, at least some fibers of the fibrous carbon comprising a particle of the iron-containing catalyst embedded at an end thereof, the catalyst particle located at the end of the fiber in which it is embedded and having a diameter between about 1.3 and about 1.6 times a diameter of the carbon fiber; wherein the fibrous carbon comprises greater than about 3 weight percent iron, wherein the agglomerations of fibrous carbon comprise buckysphere partially merged with a tube structure of the fibrous carbon.
2. The composition of claim 1 , wherein the fibrous carbon exhibit a plurality of diameters and a plurality of lengths.
3. The composition of claim 1 , wherein the bulbous or billowing conglomerations of fibrous carbon are easily felted.
4. The composition of claim 1 , wherein the fibrous carbon comprises interlocked agglomerations dispersed in an ethanol solution.
5. The composition of claim 1 , wherein the iron-containing catalyst comprises steel.
6. A composition of matter comprising agglomerations of particles of solid carbon on an iron-containing catalyst; wherein the solid carbon is selected from the group consisting of pyrolytic graphite, carbon black, amorphous carbon, and buckminster fullerenes; wherein the agglomerations of particles of solid carbon are clustered with a characteristic dimension of less than 1 millimeter; wherein the solid carbon is formed by reacting carbon dioxide with a gaseous reducing agent in the presence of an iron-containing catalyst, at least some of the particles of solid carbon bonded to a particle of the iron-containing catalyst, the particle of the iron-containing catalyst embedded in an end of the particle of solid carbon and having a dimension between about 1.3 and about 1.6 times a dimension of the particle of solid carbon, wherein the particles of solid carbon comprise Buckminster fullerene merged with a tube structure of the solid carbon.
7. The composition of claim 6 , wherein the particles of solid carbon exhibit a plurality of diameters.
8. The composition of claim 6 , wherein the agglomerations of particles of solid carbon comprise bulbous or billowing conglomerations of solid carbon.
9. The composition of claim 8 , wherein the bulbous or billowing conglomerations of solid carbon are easily felted.
10. The composition of claim 6 , further comprising an ethanol solution in which the agglomerations of particles of solid carbon are dispersed.
11. The composition of claim 6 , wherein the particles of solid carbon comprise buckminster fullerenes.
12. The composition of claim 6 , wherein the particles of solid carbon comprise pyrolytic graphite.
13. The composition of claim 6 , wherein the particles of solid carbon comprise carbon black.
14. The composition of claim 6 , wherein the particles of solid carbon comprise amorphous carbon.
15. The composition of claim 6 , wherein the iron-containing catalyst comprises stainless steel.
16. The composition of claim 6 , wherein the iron-containing catalyst comprises particles formed from decomposition of iron oxide.
17. The composition of claim 6 , wherein the iron-containing catalyst comprises a wire.
18. The composition of claim 6 , wherein the iron-containing catalyst comprises steel wool.