CARBON FOAM, SYSTEMS AND METHODS FOR FORMING THE SAME
Embodiments discloses herein relate to low-cost methods of producing a carbon foam through blending at least one carbon source with at least one solvent to form a mixture and heating the mixture at atmospheric pressure and in a non-oxidizing atmosphere to form a carbon foam. Given that the carbon foam is produced at atmospheric pressure, the methods disclosed herein may include a continuous process.
1 . A method to form a carbon foam, the method comprising:
providing a carbon source;
blending the carbon source with a solvent to form a mixture;
heating the mixture at atmospheric pressure and in a non-oxidizing atmosphere to produce a carbon foam precursor and a solvent mixture with extracted volatiles; and
heating the precursor at atmospheric pressure to form a carbon foam.
2 . The method of claim 1 , further comprising a partial solvent extraction, wherein the partial solvent extraction includes transferring the carbon foam precursor to a container and heating the mixture disposed within the container to an intermediate temperature in a non-oxidizing atmosphere.
3 . The method of claim 1 , further comprising separating the extracted volatiles from the carbon source from the solvent and further processing the extracted volatilies into carbon materials.
4 . The method of claim 1 , further comprising calcinating the carbon foam;
wherein calcinating the carbon foam comprises heating the carbon foam to a temperature from about 800° C. to about 1400° C.
5 . The method of claim 1 , further comprising graphitizing the carbon foam;
wherein graphitizing the carbon foam comprises heating the carbon foam to a temperature from about 2000° C. to about 2600° C.
6 . The method of claim 1 , wherein the carbon source includes at least one of a bituminous coal, sub-bituminous coal, pitch derived from sub-bituminous coal, a lignite coal, a pitch derived from lignite coal, coal tar, recycled green foam, and a green coke.
7 . The method of claim 1 , wherein providing at least one carbon source comprises grinding the carbon source to an average particle size of between about 1 cm to about 50 nm.
8 . The method of claim 7 , wherein grinding the carbon source comprises producing a bimodal particle size comprising a first average particle size and a second average particle size, wherein the second average particle size is different from the first average particle size.
9 . The method of claim 8 , wherein grinding the carbon source comprises producing a bimodal particle size comprising a first carbon source and a second carbon source, wherein the second carbon source includes an average particle size that is different from the first carbon source.
10 . The method of claim 1 , wherein the solvent comprises a polar solvent, a non-polar solvent, an organic solvent, an inorganic solvent, a supercritical solvent, a critical solvent, a subcritical solvent, or a combination thereof.
11 . A method to form a composite carbon foam, the method comprising:
producing a first carbon foam precursor from a mixture that includes a carbon source and a solvent;
grinding the first carbon foam precursor into a powder, wherein the powder includes an average particle size of at least about 50 nm;
adding a carbon fiber or carbon fiber tows to the first carbon foam precursor; and
heating the first carbon foam precursor and the carbon fiber or carbon fiber tows at atmospheric pressure to form a composite carbon foam.
12 . The method of claim 11 , wherein adding carbon fiber or carbon fiber tows to the first carbon foam precursor comprises drawing the carbon fiber across a surface of the carbon foam precursor and then adding an additional carbon foam precursor to incorporate the carbon fiber or carbon fiber tows within the composite carbon foam.
13 . The method of claim 12 , wherein the additional carbon foam precursor includes a second carbon foam precursor, wherein the second carbon foam precursor is different than the first carbon foam precursor.
14 . The method of claim 11 , further comprising calcinating the composite carbon foam, wherein calcinating the composite carbon foam comprises heating the composite carbon foam to a temperature from about 800° C. to about 1400° C.
15 . The method of claim 11 , further comprising graphitizing the composite carbon foam, wherein graphitizing the composite carbon foam comprises heating the composite carbon foam to a temperature from about 2000° C. to about 2600° C.
16 . The method of claim 11 , wherein the first carbon foam precursor is heated in a non-oxidizing atmosphere.
17 . A composite carbon foam, comprising a carbon foam disposed within a graphene, a graphene oxide, or a graphite outer layer.
18 . The composite carbon foam of claim 17 , wherein the graphene, graphene oxide, or graphite outer layer includes a thickness of at least about 10 nm.
19 . The method of claim 17 , wherein the characteristics of the outer layer are controlled by the type of material in an outer layer disposal process environment.
20 . The composite carbon foam of claim 16 , further comprising a carbon fiber or a carbon fiber tow incorporated within the solid porous carbon foam.
21 . The composite carbon foam of claim 16 , wherein the protective coating is formed by applying a volatile rich component to an interior surface of a container holding a precursor to the carbon foam, manipulating the volatile content of the precursor to the carbon foam during the solvent extraction processor, or a combination thereof.
22 . The composite carbon foam of claim 16 , wherein the composite carbon foam includes highly aligned crystallites in the ligaments.