TRW Gravichem : A modification of the TRW Meyers process (see next entry) in which the coal fraction which contains less pyrites is first removed by sedimentation in the ferric sulfate solution
Comyns, Alan E. Dictionary, Encyclopedic Dictionary of Named Processes in Chemical Technology (3rd ed.), Alan E. Comyns (Ed.), Boca Raton, FL, CRC Press LLC, USA 2000, http://worldtracker.org/media/library/Science/Chem istry/Synthesis/Encyclopedic%20Dictionary%20of%20N amed%20Processes%20in%20Chemical%20Technology.pdf, (Named Chem Procss - Amer) {35}