Hisatomi Taguchi

Development of an all-ceramic module with silica membrane tubes for high temperature hydrogen separation

Abstract Heat resistant hydrogen selective membranes are desired for use as membrane reactors in low-temperature hydrogen production via the steam reforming of hydrocarbons, which are usually operated over 1000 K. In addition, developing a multi-tubular type of membrane unit that can process more reactants is becoming more and more important in order to realize the practical use of membrane reactors. In this study, an all-ceramic module consisting of 6 silica membrane tubes with a comparatively large membrane area of around 0.04 m2 was fabricated by a counter-diffusion chemical vapor deposition technique. As a result, the H2/N2 ideal separation factor and the H2 permeance of the module were 1300 and 1.9 × 10−7 mol·m−2s−1Pa−1 at 873 K, respectively. In a 1000-hour thermal stability test for the silica membrane module, it was found that the H2 permeance initially decreased by about 30% and then became steady under ΔP = 0.95 MPa at 773 K.

Advanced Materials and Membranes for Applications in Hydrogen and Energy Production

General criteria for selection of materials for the processing of hydrogen separation membranes are discussed. Performance and stability standards required for applications in high temperature membrane reactors have been focused. The correlations between pore structure and stability issues of membranes made of amorphous materials, specifically silica membranes are discussed in detail.