Noncatalytic Conversion of Cellulose in Supercritical and Subcritical Water.

Water‐Tolerant Mesoporous‐Carbon‐Supported Ruthenium Catalysts for the Hydrolysis of Cellulose to Glucose

“…Sub-or supercritical water has also been applied to the hydrolysis of cellulose, but the selectivity of this method for glucose is low due to the thermal instability of glucose at high temperature. [7] For these reasons, heterogeneous solid catalysts would be favorable choices for cellulose hydrolysis, because solid catalysts can be applied under a wide range of conditions, easily separated from the reaction mixture, and reused in repeated reactions. [5] Since we reported the conversion of cellulose into sorbitol by supported Pt and Ru catalysts under H 2 pressure, [8] other groups have also reported the degradation of cellulose to sorbitol or glycols using various supported metal catalysts.…”

“…[13] The selectivity for glucose decreased and those for byproducts increased when the reaction temperature was kept at 503 K for more than 1 min. Ru/CMK-1, Ru/XC-72 (carbon black), Ru/AC (activated carbon), and Ru/C 60 were also used, to allow a comparison of the catalytic activities (Table 2, entries 3,[6][7][8][9][10]. Among these catalysts, Ru/CMK-3 had the highest cellulose conversion and glucose yield.…”

Evaluation of supercritical water gasification and biomethanation for wet biomass utilization in Japan

“…30 days are required for fermentation and 10 h for active sludge treatment. 4. Increase in active sludge is dried by a filter press to water content of 75%, and then burnt.…”

“…Also it is known that supercritical water mixes with most of the organic compounds, and rapid and homogeneous reactions of organic compounds are possible in supercritical water. Adschiri et al have shown that cellulose decomposes much more rapidly in supercritical water than in subcritical water [4]. This high reactivity can be used to decompose organic materials into gases without pretreatment of drying feedstock.…”

Hydrothermal Conversion of Cellulose to Glucose and Oligomers in Dilute Aqueous Formic Acid Solution

“…This bonding results in relatively longer reaction times for enzymatic hydrolysis, and lower yields of glucose from acid hydrolysis due to further decomposition of the products. In addition to these conventional methods, Adschiri et al [10] and coworkers [11] employed supercritical water without any additives to hydrolyze cellulose in extremely short contact times. In this process, use of fine particles of the cellulosic material may be beneficial because accurate regulation of the contact times is needed.…”