LIQUID LIQUID MISCIBILITY FOR BINARY-SYSTEMS - N-METHYLPYRROLIDONE + NORMAL-ALKANE AND PROPANENITRILE + NORMAL-ALKANE

Liquid-liquid miscibility data have been determined experimentally for binary systems of N-methylpyrrolidone with n-butane, n-hexane and n-dodecane, and propanenitrile with n-octane, n-decane, n-dodecane, n-tetradecane and n-hexadecane. All the systems present upper critical solution temperature (UCST) and those for the propanenitrile + alkane binaries vary linearly with the alkane chain length. The UCST for the N-methylpyrrolidone + alkane binaries indicate that the alkane-rich phase in the system with n-butane is close to a gas-liquid critical end point. The Weimer-Prausnitz version of the Regular Solutions Theory is used to describe the behaviour of the UCSTs.