Phase-inversion synthesize of asymmetric-structured La5.5W0.6Mo0.4O11.25-δ membranes with enhanced hydrogen permeation flux.

Asymmetric-structured La 5.5 W 0.6 Mo 0.4 O 11.25-δ (LWM) ceramic membranes were fabricated by phase-inversion process followed by sintering. Finger-like pores with distributed small pores extend through most bulk of the membrane and reduce the thickness of the dense layer. The hydrogen permeation properties of the LWM asymmetric membranes were investigated as a function of temperature and H 2 partial pressures in feed gas at the temperature range from 800 °C to 1000 °C. The hydrogen permeation flux as a function of time at 900 °C under humid atmosphere was also investigated. Compared with the conventional symmetric dense LWM membrane, the hydrogen permeation flux through the asymmetric membrane is tripled. Furthermore, the chemical stability of LWM oxides after phase-inversion process and H 2 permeation were confirmed by XRD. [ABSTRACT FROM AUTHOR]