Biomass pyrolysis oil is considered to be a promising alternative
to fossil energy for the synthesis of high value-added chemicals and
fuels. 2-Methoxy-4-methyl phenol (MMP), 4-ethylphenol (EP), 3,5-dimethylphenol
(DMP), and m-Cresol (MC) are the important phenolic
compounds in pyrolysis oil. The investigation of phase equilibrium
is crucial to design separation processes. In this work, the isobaric
vapor–liquid equilibrium (VLE) experiment, correlation, and
estimation of binary systems (cyclohexane + MMP/EP/DMP/MC) were investigated.
The experimental data were verified by the Herington test and van
Ness test, and all were thermodynamically consistent entirely. The
binary energy interaction parameters were obtained by correlating
the experimental data using NRTL, Wilson, and UNIQUAC activity coefficient
models. The average absolute relative deviations (ARD %) of T, x
1, and y
1 correlated by NRTL, Wilson, and UNIQUAC models for four
binary systems are below 0.2. In addition, the VLE data were correlated
and estimated by the UNIFAC-DMD model. The new interaction parameters
of the C–CH2 group in the UNIFAC-DMD model were
obtained and used to estimate cyclohexane + DMP systems. The ARD %
of T and y
1 for cyclohexane
+ DMP systems were 1.02 and 0.43, respectively. The estimation accuracy
of UNIFAC-DMD with new parameters was significantly improved.