Liquid-liquid equilibria (LLE) of alkane + aromatic + solvent systems is needed in relation to separation of aromatics from petroleum fractions, for example, naphtha, distillates, and lube oil. Further to earlier work, experimental LLE data for the quinary system "heptane + dodecane + benzene + methylbenzene (toluene) + furan-2-carbaldehyde (furfural)" at three temperatures (298.15, 308.15, and 318.15) K, and for the eight component system "heptane + dodecane + cyclohexane + benzene + toluene +1,2-dimethylbenzene (o-xylene) + ethylbenzene + furfural" at (303.15 and 308.15) K has been obtained. Excellent correlation of data by the nonrandom two-liquid (NRTL) model was seen for the quinary system, with the model parameters found by data regression. The model enabled tie line calculations for the full two-phase region. The UNIFAC-LLE model was also employed and the predicted results were found to be in fairly good agreement with experimental data, though not as close as in the NRTL case.