The liquid-phase submodel accounts for the vapor-liquid mass transfer, vapor-liquid equilibria, liquid convective flow from one tray to another, and the liquid-phase oligomerization and autoxidation chemistry in the bulk tray liquid. The vapor-liquid mass transfer fluxes are modeled using two-film theory with liquid volumetric mass transfer coefficient (k liq A) and Henry's law constant (k H ). k liq A is estimated using the temperature-dependent empirical correlation derived from solvent viscosity, solvent density, and solute diffusion coefficients.