(582t) Reforming of Methanol Aqueous Solution Use of Superheated Liquid-Film Concept

Hydrogen is produced by water electrolysis using renewable energy, and is regarded as an ideal energy carrier. Organic hydride is adequate for hydrogen to store, transport and utilize because of its advantages on safety and easiness-to-treat as well as of its effectiveness on energy and cost. Recently, methanol is also considered as a storable and transportable hydrogen carrier by reforming reaction of methanol aqueous solution. Moreover, it is reported that methanol is produced using carbon dioxide. Therefore, hydrogen energy utilization system using reforming reaction of methanol aqueous solution is efficient system from the view point of carbon capture and utilization. In our previous study, nanosized metal particles supported on carbon, immersed with liquid substrate, were heated externally under boiling conditions. Superheated liquid could contact with the catalyst active sites immediately after the evolution of bubbles, into which the reaction products had been enforced to desorb under boiling conditions with sharp temperature gradient. Gaseous hydrogen was disturbed by liquid film to meet the catalyst again. In this study, reforming reaction of methanol aqueous solution using superheated liquid-film concept was carried out, and the effects of the molar ratio of water to methanol (S/C ratio), and species of metal catalyst on reforming reaction of methanol aqueous solution were investigated. The effects of S/C ratio on reforming of methanol aqueous solution was investigated using Ni-Ru/C catalyst, and the optimal conditions of S/C ratio was determined 1.0. The generation rate of gas containing hydrogen, carbon oxide, and carbon dioxide increased with increasing reaction temperature. The generation rate of gas was also influenced by the species of metal catalyst, and Ni-Ru/C catalyst was the best metal from the view point of generation of gas. On the other hand, there is no generation of carbon oxide as a byproduction using Cu-Mn/C catalyst. However, the reaction rate was low. It is considered that hydrogen energy utilization system using reforming reaction of methanol aqueous solution is efficient system.