I have answered the problem but, information has been added I'm not sure how to deal with: This time, to minimize product loss, the remaining product stream needs to have a DMF composition of 10%. To achieve this, a recycle loop is used. Redraw the appropriate PFD and find unknown compositions. In particular, what fraction of exit stream was recycled? Note that you will need to choose a basis. Could you help me? I'll attach the old problem here: The feedstream contains 55 mol% DMF with remainder nitrogen. The separator is designed to remove exactly two-thirds of the Dimethy Flormamide (DMF) fed to it in pure form. Could I get the solution where the new information has been implemented?

THIS IS THE OLD PFD

Feed (E) > P XDM,P,T Separator XDME,F F0.35 XNvF= 0.45 -D Pr XDME, Py = ? XNv, pv=