【Note】
Hydrogenous Gas Recovery through Reactions of Carbonaceous Materials with Supercritical Water and CO2 Fixation
Shoji Hayashi* and Yoshiaki Iguchi**
* Nagare, Nagoya Institute of Technology
** Tsukuri, Nagoya Institute of Technology
† Correspondence should be addressed to Shoji Hayashi:
Graduate School of Materials Engineering, Nagare College, Nagoya Institute of Technology
（Gokiso-cho, Showa-ku, Nagoya, 466-8555 Japan）

Abstract
Refuse derived fuel（RDF）, as a carbonaceous material, was made to react isothermally with sub-supercritical water（400〜650℃, 200〜300 atm）and a CO2 fixation reagent, Ca（OH）2, inside a closed metallic tube reactor（7cm3）. The product gas consisted of hydrogen and a little methane gas. Addition of catalysis NaOH or KOH increased the production of gas. KOH was 2.4 times more effective in producing gas than NaOH. X-ray diffraction revealed that Ca（OH）2 and CaCO3 existed mainly in residues after reaction tests with a CO2 fixation reagent, Ca（OH）2 or CaO. Therefore, it is supposed that the overall reaction took place according to the chemical reaction below. Steelmaking slag for CO2 fixation provided maximum gas generation of 1.27 times as much as molar carbon in an RDF sample with KOH.
　　C＋H2O＋Ca（OH）2＝CaCO3＋2H2

Key words: carbonaceous materials, sub-supercritical water, hydrogen gas, CO2 fixation reagent, catalysis