A specific optimal control problem is formulated, based on the assumptions of constant boil-up and product specification, for the respective step. Numerical solutions are brought by the BOCOP solver (Bonnans et al. ). This solver, in particular, employs the direct method with a choice of discretization schemes for dynamics time discretization, which furthermore conversed the problem into finite-dimensional. In Table ., the optimal costs and the recovery rates of the respected component recovered in a two-step process are displayed. The optimal control policies for the azeotropic mixture of acetone-methanol are depicted in Figure , as the LP step in the batch rectifier/HP step in the batch stripper, respectively.