화학공학소재연구정보센터
Chemical Engineering Research & Design, Vol.88, No.10A, 1427-1431, 2010
Drying processes for preparation of titania aerogel using supercritical carbon dioxide
Supercritical carbon dioxide drying was performed for the preparation of titania aerogels from sol-gel routes. The conditions of supercritical carbon dioxide drying were 313-323 K and 7.8-15.5 MPa. The solvents in titania wet gels obtained from the sol-gel routes were replaced by acetone. The titania aerogels obtained from supercritical carbon dioxide drying form needle-like structures. In supercritical carbon dioxide drying, the extraction rates of acetone from the wet gels were measured by using an on-line Fourier transform infrared spectroscope. It was found that the titania aerogels with lower cohesion were induced from the formations of homogenous phase for carbon dioxide + acetone system and the lower extraction rates of acetone. Furthermore, titania films were prepared by the depositions of the titania aerogels on ITO-coated PET substrates. The needle-like aerogels with lower cohesion derive the titania film with high surface area. (C) 2010 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.