Synthetic fuel is the Bergius process. In this process, coal is liquefied by heating in the presence of hydrogen gas (hydrogenation). Dry coal is mixed with heavy oil recycled from the process. Catalysts are typically added to the mixture. The reaction occurs at between to and 20 to 70 MPa hydrogen pressure. The reaction can be summarized as follows: formula_1 After World War I several plants were built in Germany; these plants were extensively used during World War II to supply Germany with fuel and lubricants. The Kohleoel Process, developed in Germany by Ruhrkohle and VEBA, was used in the demonstration plant
Bitumen-based fuel associated with the phenol group of surfactants. The most well known bitumen-based fuel has been developed by Intevep, the Research and Development Affiliate of Petroleos de Venezuela SA (PDVSA), in a collaboration with BP, and is branded "Orimulsion." It is an emulsion of natural bitumen mined from the Orinoco Belt and fresh water. Bitumen-based fuel is currently used as a commercial boiler fuel in power plants in Canada, Japan, Lithuania, and China. Commonly available air pollutant control technology can limit emissions from Orimulsion to levels considered Best Available Control Technology, as defined by the United States Environmental Protection Agency. Bitumen-based