Abstract: Systems and methods for producing product gas fuel and solid char fuel from a carbon-containing feedstock are described. Feedstock is introduced into and transported through at least one substantially horizontal sublimation reaction chamber. An initial and final sublimation temperature is maintained within less than ±10° C. in an atmosphere free from external oxygen and externally supplied catalyst. The system is configured to not have any product gas leak out of the reaction chamber or oxygen leak into a hot box configured to heat the reaction chamber.

Abstract: Approaches for producing fuel from a carbon-containing feedstock are described. Feedstock is introduced into a substantially microwave-transparent reaction chamber. A microwave source emits microwaves which are directed through the microwave-transparent wall of the reaction chamber to impinge on the feedstock within the reaction chamber. The microwave source may be rotated relative to the reaction chamber. The feedstock is subjected to microwaves until the desired reaction occurs to produce a fuel. A catalyst can be mixed with the feedstock to enhance the reaction process.