Measurement and correlation of ternary vapor-liquid equilibria for methanol + glycerol + fatty acid methyl ester (methyl laurate, methyl myristate, methyl palmitate) systems at elevated temperatures and pressures

• Three VLE ternary systems were measured and correlated at high temperatures and pressures.
• The content of methanol in liquid phase increase, while glycerol and FAME decrease with pressure.
• The mutual solubility in vapor phase decreased with molecular chain length of FAME.
• VLE data was regressed by different EOS. RKS-ASPEN EOS can correlate accurately.

The phase behaviors for three ternary systems (methanol + glycerol + methyl laurate/methyl myristate/methyl palmitate) were studied at elevated temperatures (about 493.0 K, 523.0 K) and pressures by a flow-type method. The results demonstrated that the mole fractions of methanol in liquid phase increase and the mole fractions of glycerol and FAME decrease with increasing pressure. The influences of FAME molecular chain length on mutual solubility between methanol, glycerol and FAME in vapor phase were discussed. The experimental data were regressed by Redlich-Kwong-Soave equation of state (RKS EOS), RKS EOS combined with Boston and Mathias function (RKS-BM EOS) and Redlich-Kwong-Soave Aspen equations of state (RKS-Aspen EOS) with van der Waals (vdW) mixing rule. The correlated results with RKS-Aspen EOS are more accurate than other EOSs. The vapor-liquid equilibria (VLE) experimental data can be employed for designing the methanol process and phase separation in biodiesel production technology.

The phase equilibria data of three ternary systems at elevated temperatures (about 493.0 K, 523.0 K) and pressures were measured by a flow-type method. The experimental data were regressed by Redlich-Kwong-Soave equation of state (RKS EOS), RKS EOS combined with Boston and Mathias function (RKS-BM EOS) and Redlich-Kwong-Soave Aspen equations of state (RKS-Aspen EOS) with van der Waals (vdW) mixing rule.Figure optionsDownload as PowerPoint slide