Preparation and Properties of Hydrothermally Stable -Alumina-Based Composite Mesoporous Membranes
Abstract:We report here on our thermal and hydrothermal investigations comparing mesoporous -Al2O3 membrane with single and double dopant membranes prepared by the sol–gel method. Improvements in the hydrothermal stability of mesoporous -Al2O3 by transition (Ga3+) or rare-earth (La3+) cations are discussed, along with the effectiveness of double dopant (Ga3+–La3+). The amounts of Ga2O3 oxide used varied between 0.0 and 30 mol% and those of La2O3 between 6 and 15 mol%. The thermal and hydrothermal (up to 75% steam) stability of nine types of membranes fabricated on an asymmetric porous α-Al2O3 support by means of a dip-coating process was characterized by H2 gas permeation at 500°C. By conducting tests with wide variations in dopant concentrations, material characterizations, and gas permeance performance, we have been able to optimize the key parameters for hydrothermally stable systems.
Document Type: Research Article
Affiliations: 1: Japan Fine Ceramics Center, Hybrid Process Group, Nagoya 456-8587, Japan 2: Department of Chemical System Engineering, Faculty of Engineering, University of Tokyo, Tokyo 113-8656, Japan
Publication date: September 1, 2006