Synthetic fuels: are they different

The author considers three types of synthetic liquid fuels: shale oil from a surface retort, tar sands liquids and coal-derived liquids as exemplified by Exxon Donor Solvent liquid products. The ways in which such liquids differ from crude oil in chemical structure and composition are shown. The type of upgrading required to meet market specifications is described, and the possibility of modifying end-use specifications or equipment to accept the synthetic fuels is examined.