Noble metal catalysts on mesoporous SiO2 and modified carbon supports were found to enhance the activities of terphenyl. (TPh) hydrogenation and tercyclohexane (TCH) dehydrogenation without side reactions, such as cracking, hydrogenolysis, ring: opening and/or coke formation. The noble metal catalysts could be used for a reversible hydrogen storage system. Five percent Pt/SiO2 catalyst was highly active in TCH dehydrogenation without stirring, due to an easier diffusion of organic molecules to the small. catalyst particles during dehydrogenation. In view of a long-term stability in TPh hydrogenation and TCH dehydrogenation, a catalyst with relatively low Pt content on the oxidized graphite coal (Sibunit-ox) was the most promising for a hydrogen storage system because Pt agglomeration on the support was found to be much less than Pd agglomeration in the Pd/Sibunit-ox catalyst. (c) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.