Nagata, I., Fukushima, Y. and Miyazaki, K., 1992. Vapour-liquid equilibrium in the quaternary system methanol-2-propanol-acetonitrile-benzene at 55 ° C. Fluid Phase Equilibria,71: 17-27.The isothermal vapour-liquid equilibrium for the quaternary methanol-2-propanol-acetonitrile-benzene system have been determined using a modified Boublik vapour-recirculating still at 55 ° C. The experimental results are in good agreement with those calculated by the UNIQUAC associated-solution model based on binary information alone.