Liquid–liquid equilibria for quaternary mixtures of water, ethanol, and 2,2,4-trimethylpentane with fuel additives

The experimental tie-line data measured for two quaternary mixtures of the water–ethanol–2,2,4-trimethylpentane–methyl tert-butyl ether (MTBE) and water–ethanol–2,2,4-trimethylpentane–tert-amyl methyl ether (TAME) systems at the temperature 298.15 K and ambient pressure are presented. The experimental quaternary liquid–liquid equilibrium data have been satisfactorily correlated by using a modified form of the UNIQUAC model with binary, ternary and quaternary parameters. The calculated results are further compared with those obtained from the extended UNIQUAC model of Nagata.