La_(0.8)Sr_(0.2)Cr_(0.5)Fe_(0.5)O_(3-δ) (LSCF)-Zr_(0.8)Y_(0.2)O_(2-δ) (YSZ) based multilayer membrane for CO_2 decomposition

摘要

A La_(0.8)Sr_(0.2)Cr_(0.5)Fe_(0.5)O_(3-δ) (LSCF)-Zr_(0.8)Y_(0.2)O_(2-δ) (YSZ) based multilayer membrane was fabricated by a combination of dual-layer phase inversion tape casting, slurry coating and co-sintering. LSCF-YSZ was adopted as the oxygen separation layer. A porous YSZ substrate with a continuous transitional finger-like pore structure was prepared, and a LSCF-YSZ active layer with a fine sponge-like pore structure was introduced between the functional LSCF-YSZ oxygen separation layer and YSZ substrate. The asymmetric membrane exhibits good chemical stability and acceptable oxygen permeation under stringent conditions. An oxygen permeation flux of 0.041, 0.068 and 0.15ml(STP)cm~(-2)min~(-1) was gained at 900℃ for operation under air/argon, CO_2/CH_4 and CO_2/H_2 gradient, respectively. The apparent activation energy for oxygen permeation was 175.61 ± 18.45, 97.21 ± 2.94 and 79.41 ± 6.26 kJ/mol under air/ argon, CO_2/CH4 and CO_2/H_2 gradients respectively. The preliminary results show that the membrane may be promising for applications in the recycling of CO_2 and treatment of hydrocarbons.