(244a) Carbon Negative Biomass Refining System Based On Alkaline Hydrothermal Treatment Technology

A novel synthesis scheme of hydrogen from biomass is developed based on alkaline hydrothermal treatment. The proposed alkaline hydrothermal treatment is a less-studied method of biomass conversion but one with great transformational potential since it can be achieved with much higher overall conversion, the synthesized gaseous product is carbon-free and an option of carbon storage is inherently incorporated into the reaction scheme. The central concept pursed in this study is the use of a strong base in removing carbon from the C, H, O equilibrium that can be produced in mixtures of biomass and steam. The previous research has demonstrated several examples of interactions between simpler biomass (i.e., glucose and cellulose) and a strong base (i.e., NaOH) that resulted in hydrogen production with high purity (e.g., less than 10 ppm of CO) at relatively low reaction temperature and pressure (i.e., 473-773K and 1 atm). Therefore, the product gas can be directly applied to a PEM fuel cell system without further conditioning. Alkaline biomass reforming is driven in part by the heat of carbonation and the main concerns regarding this technology would be the method of hydroxide recovery. The reaction kinetics and conversion of the proposed biomass conversion system are investigated for the varied reaction temperature, biomass-hydroxide ratio, catalysts, partial pressure of H2O, etc. A series of analytical techniques such as GC, MS, NMR, ATR-FTIR and XRD are employed to fully identify each individual species in the product stream and to provide insights into this new reaction pathway toward biomass-driven hydrogen.