I have no experience distilling, though I understand the basics about it. When two liquids with different boiling points are mixed, you can sometimes separate them by boiling away one of the liquids, leaving the other behind. Sometimes multiple iterations of this process can enhance the process. If the important substance is the one that boils first, the gas form can be collected and condensed back to liquid. This is usually done with liquors and other alcohol products, but in principle should be possible with many substances.
I have been reading up on fermentation with Clostridium acetobutylicum bacteria. Some strains produce acetone, butanol, and ethanol in a 3-6-1 ratio. From my reading, it's not entirely certain what yields could be expected, but I would imagine these are low, and that what's left over in a fermentation vat is still mostly water. Plus, I suppose, some sediment and biological contaminants that won't filter out entirely.
Acetone's boiling point 58° according to Wikipedia, far below the boiling point of water, even significantly below the boiling point of ethanol. Can this be distilled out (first) to some reasonably high purity?
Would it then be simply a matter of raising the temperature to next remove the ethanol, and after that the water (both mostly waste products to be discarded responsibly)? Would the butanol be left in the vat afterward at some reasonable level of purity (contaminants aside)?
I am interested in both the acetone and butanol, and would like to be able to make modest quantities of both, but if I had to take one or the other the butanol is the more important of the two.