Process for making isooctenes from dry 1-butanol

A process for making at least one isooctene comprising:

• (a) obtaining a fermentation broth comprising recombinant microorganisms and 1-butanol wherein the fermentation broth is substantially free of acetone and ethanol;
• (b) separating dry 1-butanol from said fermentation broth to form separated dry 1-butanol comprising the steps of heating a stream of fermentation broth and introducing the heated stream into a beer column removing from the beer column a 1-butanol water azeotrope and condensing it to a biphasic liquid stream having an upper phase and a lower phase and introducing a stream of the upper phase into a butanol separation column
• (c) contacting the separated dry 1-butanol of step (b), optionally in the presence of a solvent, with at least one acid catalyst at a temperature of about 50 degrees C. to about 450 degrees C. and a pressure from about 0.1 MPa to about 20.7 MPa to produce a reaction product comprising said at least one isooctene;
• and
• (d) recovering said at least one isooctene from said reaction product to obtain at least one recovered isooctene.