Catalytic Partial Oxidation of Nascent Volatiles from Rapid Pyrolysis of Woody Biomass by Using Noble Metal Supported Alumina Foam

Abstract

In-situ catalytic partial oxidation of volatiles derived from rapid pyrolysis of Japanese cedar sawdust was studied with a two stage fixed bed reactor (TS-FBR) with the primary purpose to find a reactor configuration that enables to convert tarry components into non-condensable fuel gas efficiently. The TS-FBR consisted of two sections; the upstream one for the rapid pyrolysis of the sawdust to generate nascent volatiles and the downstream one for the In-situ reforming of the volatiles. A platinum or rhodium supported alumina foam was used as the catalyst and placed at the downstream section. It was found that the selectivity of oxygen consumption to tar conversion was greatly influenced by the catalyst location. A simultaneous contact of the volatiles with the catalyst surface and mixing of the volatiles and oxygen within the foam enabled to get a better conversion of tar as well as a selectivity of synthesis gas. It was found that more than 70 % of hydrogen and 64 % of carbon in the feedstock could be converted into hydrogen and carbon monoxide, respectively, at an optimized condition of T = 800 °C, oxygen/carbon molar ratio = 0.25, and contact time = 100 ms.