TiO sub 2 permselective membranes

Conference · Tue Jan 01 00:00:00 EST 1991

OSTI ID:5545393

Kim, Soojin; Gavalas, G

Hydrogen permselective membranes were synthesized by chemical vapor deposition of TiO{sub 2} or SiO{sub 2} layers within the pores of Vycor tubes used as supports. The reaction mechanism and kinetics of TiO{sub 2} or SiO{sub 2} formation were investigated in terms of the heterogeneous reactions between gaseous TiCl{sub 4} or SiCl{sub 4} with hydroxyl groups in the solid and between gaseous H{sub 2}O and chloride groups in the solid. The growth of the oxide layers can be characterized as a polymerization proceeding by alternating reactions of the gaseous reactants with groups on the solid surface. In addition, condensation reactions occur between surface chloride groups and nearby hydroxyl groups or two neighboring hydroxyl groups, that contribute to the overall mechanism of the oxide layer formation. For the case of TiO{sub 2} deposition, chlorination of the surface hydroxyl groups seems to be the rate-limiting step in the growth of the deposit layer.

• Research Organization: California Inst. of Tech., Pasadena, CA (United States). Div. of Chemistry and Chemical Engineering
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FG22-89PC89765
• OSTI ID: 5545393
• Report Number(s): CONF-911133-11; ON: DE92009988
• Resource Relation: Conference: American Institute of Chemical Engineers (AIChE) annual meeting, Los Angeles, CA (United States), 17-22 Nov 1991
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
MEMBRANES
SYNTHESIS
SILICON OXIDES
CHEMICAL VAPOR DEPOSITION
TITANIUM OXIDES
VYCOR
VAPOR DEPOSITED COATINGS
CHEMICAL REACTION KINETICS
POLYMERIZATION
CHALCOGENIDES
CHEMICAL COATING
CHEMICAL REACTIONS
COATINGS
DEPOSITION
KINETICS
OXIDES
OXYGEN COMPOUNDS
REACTION KINETICS
SILICON COMPOUNDS
SURFACE COATING
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
360601* - Other Materials- Preparation & Manufacture