Studies on thermodynamic properties of (a hydrocarbon+a branched chain ether) mixtures

The solid–liquid equilibrium, SLE, has been measured for {a hydrocarbon (C18–C28)+methyl 1,1-dimethylethyl ether (MTBE), or ethyl 1,1-dimethylethyl ether (ETBE)} mixtures from 280 K to the melting temperature of the hydrocarbon. Experimental solubilities are compared with values calculated by means of the Wilson, UNIQUAC and NRTL equations utilizing parameters taken from SLE. The liquid–liquid equilibrium, LLE, of {water+(ETBE), or methyl 1,1-dimethylpropyl ether (MTAE), or ethyl 1,1-dimethylpropyl ether (ETAE)} has been measured from 300 K to 360 K. The mutual solubility in binary systems of (heptane, or 1-heptene, or toluene+MTBE, or ETBE, or MTAE) in the temperature range from 273 K to 298 K has been measured. All these systems have been found to be homogenous. The excess molar volumes, VmE, at the temperatures 298.15 K and 308.15 K have been measured for the mixtures of {a hydrocarbon (hexane, octane, decane, dodecane, tetradecane, hexadecane), or cyclohexane or 1-heptyne+a branched chain ether (ETBE)}. The excess molar volumes of all mixtures except for 1-heptyne are positive over the whole composition range. The experimental results have been correlated and compared with the results from Prigogine–Flory–Patterson (PFP) theory.