An Effective Coal Liquefaction Solvent Obtained from the Vacuum Pyrolysis of Waste Rubber Tires

Oil derived from vacuum pyrolysis of waste rubber tires was used as a coal liquefaction solvent with a high-volatile A bituminous coal and a Mo catalyst. The vacuum-pyrolyzed tire oil along with the Mo catalyst was found to convert over 90% (daf) of the coal to gas, oil, and asphaltenes. Reactions were carried out in tubing reactors heated to 430 °C under 1000 psig (cold) of hydrogen gas. The vacuum-pyrolyzed tire oil (PTO) obtained from waste rubber tires contained various polyaromatic molecules which have been shown to be beneficial in coal liquefaction. Coal conversion was found to be hydrogen pressure dependent for reactions where coal and PTO were coprocessed together. Conversion results show that most of the coal reacted within the first 10 min of coprocessing. Electron probe microanalysis (EPMA) detected the presence of Mo inside coal particles after 20 min of coprocessing coal and PTO.