Separation of a solution of n-butanol and nitroethane
Use counter-current extraction.
I'm not sure about solvents, but let's say that I can separate nitromethane from water by distillation. Also that butanol can be separated from ether by distillation. (as I remember ether and water aren't miscible...)
So I line up 7 sepatory funnels.
Into sepatory funnel #4 I put my mixture and 50 ml of water and 50 ml of ether. Equilibrate then water phase goes to sepatory funnel #5 and ether phase goes to sepatory funnel #3. Sepatory funnel #4 is now empty.

In sepatory funnel #5 I add 50 ml ether, Equilibrate then water phase goes to sepatory funnel #6 and ether phase goes to sepatory funnel #4
In sepatory funnel #3 I add 50 ml water, Equilibrate, then water phase goes to sepatory funnel #4 and ether phase goes to sepatory funnel #2

So basically I have the water extracts going one way and the ether extracts the other way.