Conditions for Acid Fermentation of Molasses for Effective Production of Propylene from Biomass

Biomass resources have attracted attention because they are renewable and can be converted into feedstock for producing valuable chemicals such as olefins and aromatics. The present study proposes a two-step operation for producing bio-oils or chemicals from biomass to improve the quality of product and catalyst life. The first step is fermentative production of oxygen-containing compounds such as butyric acid from molasses as biomass. In the second step, the product is converted catalytically to propylene. The feasibility of the two-step process depends on the fermentation step. To realize the efficient acid fermentation, conditions were studied for producing butyric acid in high selectivity in a short period. Under our optimized conditions, selectivity was improved from 25.4 to 73.5 C% and the fermentation period was shortened from 13.5 to 1.5d. Catalytic conversion of the fermentation product over zeolite gave a propylene yield of 25 C%. The results clearly show feasibility of the two-step processes for propylene production from molasses.