Again starting values for the optimization variables are needed. A possibility would be to use again streams obtained from a V min diagram. In our numerical experiments we were able to find solutions using the new approach starting with these streams. Unfortunately, the optimization using Aspen Plus R as simulator did not converge. The V min diagrams assume an infinite number of stages. In the current example the number of stages is too small so that the approximation made with an infinte number is not very close. The initial simulation performed with values of the V min diagram predicted purities of around 60% in some of the product streams. This is why, it was suggested to adjust the initial flowrates of the internal streams Ränger and Grützner 2021. The flow rates are sufficient to calculate the initial specifications used in the simulation with Aspen Plus R . However, initial values for the concentrations are needed for the new approach. The new approach is not too sensitive to the choice of initial values for the . As pure components are assumed in the product streams, the flow rate for each product stream must be 25 mol/h. The flow rates for each component of a stream are again bounded from below by 0 and from a above by 10 kmol/h. The heat duty and the condenser duty are assumed to lie in the intervals [1 kW, 10 kW] and [-10 kW, -1 kW].