Abstract: A method and apparatus for the reduction of carbon dioxide emissions by the on-hoard treatment of a portion or all of the hydrocarbon fuel used to power an internal combustion engine mounted in a conventional transportation vehicle, utilize known decarbonization technology to break the fuel's hydrogen-carbon bond. The compounds are then cooled and separated into (1) elemental carbon powder that is stored on-board for later recovery and industrial use, and (2) hydrogen, or a hydrogen-rich gas stream, that is burned as a fuel in the ICE and/or diverted to other on-board energy related applications.