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We developed a membrane reactor that can produce high-purity hydrogen in one step from methylcyclohexane. This membrane reactor combined a hydrogen-selective amorphous silica membrane prepared with dimethoxydiphenylsilane and oxygen and employing counter-diffusion chemical vapor deposition, and Pt/Al 2 O 3 catalyst. The silica membrane showed excellent hydrogen permeance at 573 K of the order of 10 -6 mol m -2 s -1 Pa -1 and high hydrogen/sulfur hexafluoride permselectivity of around 10 4 . The membrane reactor exhibited equilibrium shifts as expected under reaction temperatures ranging from 473 to 553 K and reaction pressures ranging from 0.1 to 0.25 MPa, and these performances were successfully predicted using a simulation model, which was also developed in this study. Finally, we demonstrated that hydrogen with purity as high as 99.95% was produced from methylcyclohexane in the membrane reactor without using carrier gas or sweep gas.

The Shirasu porous glass (SPG) membrane emulsification technique was employed for the preparation of monodispersed chitosan microspheres with the diameter controlled to be in the range from submicrometers to 10 μm. Three preparation methods were used in this study: (1) a cross-linking method with glutaraldehyde, (2) an interaction method with alginate, and (3) a drying-in-liquid method with aqueous sodium hydroxide medium. In every preparation method, various SPG membranes with different pore sizes were used for microsphere formation, and the fabrication mechanism for the microspheres was elucidated. It was successfully shown from these detailed investigations that the average diameters of the chitosan microspheres were controlled in the range of submicrometer to 10 μm by the pore sizes of the SPG membranes for preparing chitosan emulsions by method 1, alginate emulsions by method 2, or chitosan emulsions by method 3.

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