BUTANOL FERMENTATION LIQUOR SEPARATION BY REVERSE OSMOSIS (SOLVENT, MEMBRANE)

The problem of dilute solvent concentration in butanol-acetone fermentations can be solved by using reverse osmosis to dewater the fermentation liquor. Polyamide membranes have a potential application in a butanol-acetone fermentation and exhibited rejection rates as high as 98 percent. Optimum rejection of butanol in an aqueous mixture occurs at hydraulic recoveries of 50-70 percent and in a fermentation liquor at recoveries of 20-45 percent. Flux ranged from .5 to 1.8 L*m('-2)*min('-1) for an aqueous mixture and .05 to 0.6 L*m('-2)*min('-1) with a liquor depending upon pressure and recovery values.