• Membrane Journal
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• v.21 no.2
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• pp.148-154
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• 2011

Metal-ceramic composite membrane have been developed to separate hydrogen from mixed gases, particularly product streams generated during coal gasification and methane reforming. Cermet membrane was fabricated with palladium as hydrogen-permeable metal and $Y_2O_3$-stabilized $ZrO_2$ (YSZ) as ceramic supporter. As-prepared membrane showed dense structure with continuous channel of palladium. The hydrogen flux of Pd/YSZ membrane have been measured in the range of 0.5~2 atm with 100% hydrogen gas. The results indicate that the hydrogen flux was 0.333 mL/$min{\cdot}cm^2$ at $450^{\circ}C$ and 2 atm. The crack was formed in the surface and cross-section of membrane.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.2
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• pp.70-74
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• 2011

[ $(Ca,Mg)_{0.15}Zr_{0.7}O_{1.7}$ ]ceramics was investigated for the application to SOFC ceramic supporter with high porosity and mechanical strength. $ZrO_2$ powder was prepared by combustion method with glycine using the solution of $ZrO(NO_3)_2{\cdot}2H_2O$ dissolved into deionized water and calcination at $800^{\circ}C$ Porous $(Ca,Mg)_{0.15}Zr_{0.7}O_{1.7}$ ceramics was prepared by sintering the mixture of prepared $ZrO_2$ powder, dolomite and carbon black at $1200{\sim}1400^{\circ}C$ for 1 h. The open porosity ofthe $(Ca,Mg)_{0.15}Zr_{0.7}O_{1.7}$ ceramics sintered at $1300^{\circ}C$ was over 30 % and increased linearly with the amount of carbon black. The crystal structure of $(Ca,Mg)_{0.15}Zr_{0.7}O_{1.7}$ ceramics consisted of single cubic phase. The open pore of this ceramics was connected continuously and distributed well on the whole. This ceramics sintered at $1300^{\circ}C$ showed the porosity from 32 to 55 % and mechanical strength from 90 MPa to 30 MPa with increasing the content of added carbon black.

• Membrane Journal
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• v.20 no.1
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• pp.69-75
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• 2010

Cermet membrane was fabricated with tantalum as hydrogen-permeable metal and $Y_2O_3$-stabilized $ZrO_2$ (YSZ) as ceramic supporter. Ta/YSZ cermet membrane was prepared through pre-sintering in He atmosphere and then main sintering under high vacuum and the impurities to originate from sintering and brazing could be removed by mechanical polishing. As-prepared membrane showed dense structure with continuous channel of tantalum. Hydrogen permeation experiment was conducted in the region of $200{\sim}350^{\circ}C$ using Ta/YSZ membrane coated with Pd for hydrogen dissociation. The crack in membrane was formed at $300^{\circ}C$ and the Pd coating layer has flaked off in spots. XRD results showed that tantalum reacted with hydrogen to form $Ta_2H$. The lattice expansion by $Ta_2H$ caused deterioration for membrane.