Enhanced ABE fermentation with high yielding butanol tolerant Clostridium strains

摘要

A method and system for high-yield fermentation comprises using Clostridium species having tolerance of a concentration of butanol of up to 15% (150g/l or 2 mol/l) in a packed-bed bioreactor, to produce ABE (acetone butanol ethanol) solvents. The microorganisms are preferably grown on a solid support such as bone-char particles. Preferably the process yields in excess of 6g/l.h butanol. A bioreactor comprising a packed bed zone, a bed expansion zone and a particle disengagement zone (to prevent egress of a solid support) is separately claimed. Preferably the bioreactor is configured to alternate between packed bed and expanded bed modes of operation.