Abstract
We have investigated a method to produce carbonaceous adsorbents from moist and partially carbonized residues generated from a biomass refinery process in which biomass feedstock is converted into bio-chemicals. A series of laboratory-scale tests were conducted with some existing biomass (e.g., Japanese cedar and bamboo). The biomass feedstock was subjected to a steam-explosion treatment at 230°C to obtain saccharides and furfurals from the aqueous phase by the decomposition of the hemicelluloses fraction. The exploded solid material was further decomposed under the hydrothermal condition at 260 °C and water-soluble chemicals were separated. We used the solid residue from the series of treatments to produce chemicals, as the raw materials of the carbonaceous adsorbents. The solid residue was carbonized at 350 °C in aqueous phase with no oxidant, followed by aqueous phase oxidation of the intermediate at the same temperature under the coexistence of hydrogen peroxide. Thus-obtained carbonaceous materials were found to have mesoporous structures with 300-400 m2/g in BET surface area by nitrogen adsorption. The surface area was around one-third of typical commercial activated carbons.
