Preparation and characterization of titania-deposited silica composite hollow fiber membranes with high hydrothermal stability.
Hydrothermal stability of a porous nickel-supported silica membrane was successfully improved by deposition of titania multilayers on colloidal silica particles embedded in the porous nickel fiber support. Porous nickel-supported silica membranes were prepared by means of a dipping-freezing-fast drying (DFF) method. The titania layers were deposited on colloidal silica particles by repeating hydrolysis and condensation reactions of titanium isopropoxide on the silica particle surfaces. The deposition of thin titania layers on the nickel-supported silica membrane was verified by various analytical tools. The water flux and the solute rejection of the porous Ni fiber-supported silica membranes did not change after titania layer deposition, indicating that thickness of titania layers deposited on silica surface is enough thin not to affect the membrane performance. Moreover, improvement of the hydrothermal stability in the titania-deposited silica membranes was confirmed by stability tests, indicating that thin titania layers deposited on silica surface played an important role as a diffusion barrier against 90 degrees C water into silica particles.
School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Republic of Korea.
Young-Nam
YN
Kwon
In-Chul
IC
Kim
D003460:Crystallization / Q000379:methods; D006358:Hot Temperature; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008567:Membranes, Artificial; D008968:Molecular Conformation; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
D046911:Macromolecular Substances; D008567:Membranes, Artificial; D014867:Water; C009495:titanium dioxide; D012822:Silicon Dioxide; D014025:Titanium