Thanks! We haven't done a unique analysis yet, but here is a paper that does a good overview of energy balances and efficiencies for CO2 to fuels and products. In their separations discussion you can see why distillation of alcohols is not favorable. A membrane approach is approx. 6x better, but until the CNT membrane was shown to do this job, there was no practical way to do the separation at this efficiency.

https://www.cell.com/joule/fulltext/S2542-4351(18)30042-4