Vapor Pressures of Phenolic Compounds Found in Pyrolysis Oil

Oil produced from pyrolysis of Kukersite oil shale and lignocellulosic biomass contains significant amounts of phenolic compounds. Here, we present new experimental vapor pressure data for two such compounds (4-ethyl-2-methoxyphenol and 5-methylresorcinol) and also for a mixture of phenolic compounds extracted from pyrolysis oil (Honeyol). Vapor pressure data were measured by differential scanning calorimetry, in accordance with the ASTM E 1782 standard test method. The measurements were conducted in the pressure range from 0.89 kPa to atmospheric pressure. The measured temperature ranges for the vapor pressure were 374.5-509.1 K for 4-ethyl-2-methoxyphenol, 428.0-565.0 K for Honeyol, and 429.4-565.8 K for 5-methylresorcinol. Density data for 4-ethyl-2-methoxyphenol were also measured at 293.15-363.15 K. The experimental vapor pressure and density data for 4-ethyl-2-methoxyphenol were fitted using the PC-SAFT equation of state, and the vapor pressure data for the other compounds were fit using the Antoine equation. Enthalpies of vaporization were also calculated. The properties of these compounds were then compared to the literature data for other pure phenolic compounds and mixtures of the phenolic compounds from Kukersite shale oil. This comparison indicates that some pure compounds, such as 4-ethyl-2-methoxyphenol, could be used as model compounds for estimating the properties of the phenolic portion of pyrolysis oil.