RAPID AND SELECTIVE CONVERSION OF CELLULOSE TO VALUABLE CHEMICAL INTERMEDIATES WITH SUPERCRITICAL WATER Mitsuru Sasaki a,b* , Gaku Sekiguchi b , Tadafumi Adschiri c , and Kunio Arai b a Genesis Research Institute, Inc., 4-1-35 Noritake-shinmachi, Nishi-ku, Nagoya 451-0051, Japan; b Department of Chemical Engineering, Faculty of Engineering, Tohoku University, 07 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan; c Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan. E-mail: sasaki@arai.che.tohoku.ac.jp ; Fax: +81-22-217-7246. INTRODUCTION Development of a new environmentally friendly method that valuable chemical intermediates could be recovered from cellulosic biomass in rapid and selective manner using supercritical water has been studied. So far, it was found that microcrystalline cellulose could solubilize with rapidity into near- and supercritical water, followed the rapid hydrolysis to cellooligosaccharides and glucose [1]. Also, in our previous work [2], it was proposed the method for super-rapid enzymatic hydrolysis of microcrystalline cellulose using the solubilization of the cellulose in near- and supercritical water. Further, kinetic studies regarding some carbohydrates in near- and supercritical water were conducted. As a result, the major reaction paths of the carbohydrates and the controllability of each reaction path by the change in temperature and pressure at these conditions were made clear [3-10]. However, few researches regarding the elucidation of the reaction mechanism of microcrystalline cellulose in near- and supercritical water have been reported. In this study, experiments of microcrystalline cellulose conversion in supercritical water (385-415 o C, 20-40 MPa, and 0.02-4.0 seconds) were conducted and the reaction mechanism of microcrystalline cellulose was estimated based on the detailed product analyses. Next, reaction conditions at which some chemical intermediates could be rapidly and selectively produced from microcrystalline cellulose in supercritical water were elucidated. I – EXPERIMENTAL AND ANALYTICAL SECTION Microcrystalline cellulose (average degree of polymerization (DP av ): 230) purchased from Merck (Avicel ® , No. 2331) was used as a starting material. A continuous flow-type reactor with slurry feed pump was employed for the experiment. Figure 1 shows a schematic diagram of the experimental setup. First, distilled water was fed at a flow rate of 21 g min -1