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Reactions of tetralin with tritiated gaseous hydrogen were carried out at 5.00 MPa and at 200−400 °C on several noble metal catalysts prepared:  Pt/Al2O3, Pd/Al2O3, and Pt−Pd/Al2O3. Hydrogenation and dehydrogenation activities of the catalysts were compared. By tracing changes in the radioactivities of 3H in the products before and after reaction, amounts of the hydrogen exchange between tetralin and tritiated hydrogen were measured to determine the behavior of hydrogen in the reaction. Further, effects of sulfur present in the feedstocks on the catalytic performance were investigated and resultant differences in the sulfur tolerance among the catalysts were clarified.

Advantages of using organic solvents in solvolysis of lignocellulosic biomass, as compared to water, are the increase in the energy density of the product, and to selectively produce valuable compounds containing oxygen.The liquefactions of cellulose, rice straw, and red pine were conducted in a batch reaction system in the presence of solid catalysts and several protonic solvents, such as methanol and ethylene glycol. In the solvolysis of cellulose in methanol, methyl-glucopyranosides were the main products formed via the addition of H + and OCH3 -in the presence of a solid catalyst. The decomposition rates of cellulose in various solvents decreased in the order of water > methanol > ethylene glycol > 1-butanol. This may suggest that the solvents with large self-dissociation constant (K SH) enhance the solvolysis of cellulose. In addition, the pore structure and acidity of a solid acid catalyst and type of lignocellulosic biomass also affected the solvolysis. The maximum liquefaction rates of rice straw and red pine in ethylene glycol using a sulfated zirconia catalyst at 453 K for 6 h were ca. 78.7% and 97.5%, respectively.