Effect of Mass Ratio of Solvent to Solute and Pressure in Supercritical Fluid Extraction of Coal Tar

摘要

Coal tar sample was extracted by supercritical n-pentane. The mass ratios of solvent to solute were researched in different pressures and the extraction yields were explored in 4-12MPa at 215°C. The results show that, the mass ratio affects extraction yield distinctly and the extraction yield increases gradually with the rise of pressure. The mass ratio was defined as 1:9 and 1:12 when the pressure was below and above 8MPa respectively. A maximum extraction yield was achieved during 10-12MPa as 71.24%. An empirical extraction yield-pressure curve was calculated as EY=34.857p~(0.3042) (%).