NOVELTY - Processing a hydrogen donor comprises dissociating a hydrogen donor into dissociation products by adding energy to the hydrogen donor, where the energy includes waste heat generated by a process other than dissociating the hydrogen donor, and providing at least one of a structural building block based on at least one of carbon, nitrogen, boron, silicon, sulfur and a transition metal and a hydrogen-based fuel from the dissociation products.    USE - The method is useful for processing hydrogen donor for producing hydrogen fuels and structural materials.    ADVANTAGE - The improved method is capable of producing clean-burn hydrogen-based fuels in an economical manner.    DETAILED DESCRIPTION - Processing a hydrogen donor, comprises: either dissociating a hydrogen donor into dissociation products by adding energy to the hydrogen donor, where the energy includes waste heat generated by a process other than dissociating the hydrogen donor, and providing at least one of a structural building block based on at least one of carbon, nitrogen, boron, silicon, sulfur and a transition metal and a hydrogen-based fuel from the dissociation products; or dissociating a first hydrogen donor mass into first dissociation products; from the first dissociation products, providing at least one of the structural building block, and the hydrogen-based fuel, transferring heat from the structural building block, the dissociation products, and the hydrogen based fuel to a second hydrogen donor mass, and dissociating the second hydrogen donor mass into second dissociation products. An INDEPENDENT CLAIM is included for processing a hydrocarbon, comprising: dissociating a first hydrocarbon mass into first dissociation products by adding energy to the hydrocarbon mass, where the energy includes waste heat generated by a process other than dissociating the hydrocarbon mass and energy from a sustainable energy source, and the first hydrocarbon mass has a first dissociation energy; providing (a) a carbon-based structural building block and (b) a hydrogen-based fuel having a second dissociation energy greater than the first dissociation energy from the first dissociation products; transferring heat from the structural building block, the hydrogen-based fuel, and the dissociation products to a second hydrocarbon mass; and dissociating the second hydrocarbon mass into second dissociation products.    DESCRIPTION OF DRAWING(S) - The shows a schematic view of a system for processing hydrogen donor.    Reactor (310)    Donor distributor (315)    Donor vessel (330)    Steam/water source (340)    Radiant energy/reactant source. (350)