Patent ID: 7306635

Claim:
A method for the production of a coal-based cellular product comprising a matrix of cells having cells of a different density comprising: selecting a first coal-based precursor ground to a particle size below about 1 mm for providing a matrix of an appropriate strength and density; selecting a second coal-based precursor ground to a particle size below about 1 mm, having a different particle size than that of said matrix, said second coal-based precursor when expanded providing at least one of an integral stiffener, a load path, a heat transfer path, and a mass transfer path; loading each of said first and second coal-based precursors into first and second volumes of a mold, wherein first and second coal-based precursors are separated by partitions within the mold; heating said mold under a non-oxidizing atmosphere to a temperature ranging from about 300° C. to about 700° C. and soaking at this temperature for a period of from about 10 minutes to about 12 hours; and controllably cooling said coal-based product.