Example 11
Alternative feedstocks to caking coals were explored as source materials for carbon foam. In one series of experiments, a foaming pitch derived from non-caking coal prepared as described above was used as a feedstock.
90 g of foaming pitch with a particle size range of 30-50 mesh was weighed and transferred to a 250 mL beaker and 15 g of a flux agent composed of high fructose corn syrup and recycled coal volatiles as described previously was added. The contents were mixed for a period of time until the mixture was homogeneous. The foaming mixture was loaded into a crucible and converted into carbon foam using microwave radiation at 20% power for 5 min. The foam was covered with a ceramic lid and calcined in one step in a non-oxidizing environment as described previously.
A thin layer of a graphene-type compound was found on the lid of the crucible after this experiment, showing that the method can provide an additional carbon species from vapors expelled during the heat treatment and calcination processes disclosed herein. Examples of graphene-type layers formed on carbon foams can be seen in
