Preparation of TiO₂ Porous Gel for the Application as Catalytic Support

Abstract

Xerogels of large specific surface area have been successfully prepared by optimizing sol-gel process without any templates. It was found that the optimum solvent to obtain gels of large specific surface area is 1-propanol and the optimum molar ratio of solvent to alkoxide is 10. It was also clarified that the consecutive addition of water to reaction system by introducing humidified air is critical to specific surface area and that with humidified air the less initial content of water can provide gel of larger specific surface area. Consequently silica gel with specific surface area of 1869 ‍m²/g could be obtained. Titania gel with specific surface area of 597 ‍m²/g was successfully prepared by using ammonium acetate as catalyst together with above mentioned strategy.

Obtained titania gel was used as support material of Ni nanoparticle and the catalytic activity was tested then compared with commercially available non-porous titania fine particle and commercially available silica gel. As a result, the significance of catalyst-support interaction and improvement of loading amount of catalyst nanoparticles attributed to porosity were confirmed.