Simulation studies of batch distillation of some non-ideal binary systems have been carried out and reported in this work. Differential distillation as well as batch distillation at total reflux has been simulated through a semi-rigorous unsteady state mathematical model, implemented via codes developed in-house. The Wilson model has been used to represent non-ideality in the liquid phase and predict-vapour-liquid equilibrium (VLE) data. Parametric studies of the composition and temperature profiles have been carried out. Heating and cooling requirements for batch distillation operation have also been estimated. The model presented here can be used for simulating the start-up of any distillation column for even multi-component non-ideal systems, as long as the VLE data are available for them, without requiring any commercial simulation software. The model can also be extended to simulation of batch distillation columns with a finite value of reflux ratio after suitable modification of the governing equations. Thus it can be used for preliminary design work as well.