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Alloy foam-supported SOEC is fabricated. Nickel-iron (Ni-Fe) alloy foam (Porosity: 5-130 ppi) is used for cell support. Single thin-cell composed of Ni- Sc0.1Ce0.05Gd0.05Zr0.89O2 (SCGZ) cathode, SCGZ electrolyte and Ba0.5Sr0.5Co0.8Fe0.2O3- δ (BSCF) anode is fabricated. Electrode powders are mixed with additives forming as slurry for wet chemical coating. 70%weight content of cermet provides smooth surface and sufficient viscosity to prevent slurry sweep through the porous foam. However, severe cracking is clearly seen on the surface of the cell because of mismatching of thermal expansion coefficient (TEC) during sintering. Therefore, the cell with three cathode layers having TEC gradient (13.83, 13.62 and 13.40 ppmK-1) and %weight content of cermet gradient (70%, 60% and 50%weight) is fabricated. Heating rate and steps are controlled at 0.5˚C/min (600 ˚C), 3˚C/min (800 ˚C) and 1˚C/min (1,300˚C, 4 h) to burn off additives before sintering.

Thermally self-sustained double reactor (TSSDR) operating without external heat source consists of dual channels for endothermic and exothermic reactions. Hydrogen (H2) is produced from wasted glycerol by aqueous-phase glycerol reforming (APGR) at 200-250 ºC and 20-25 bar while carbon dioxide (CO2) is a by-product. Produced H2 and CO2 are used as raw materials for methanol synthesis (MS) at 200-250 ºC and 50-80 bar. Methanol synthesis and glycerol reforming occur at inner and outer channels of TSSDR, respectively. The TSSDR is fully packed with catalyst. Generated heat of exothermic reaction is sufficient for endothermic reaction. Main products of glycerol reforming in gas phase are H2 and CO2 while CO and CH4 are by-products. All products in gas phase are totally recycled as a feed stream for exothermic channel. CO and CH4 in feed reduce CO2 conversion and methanol yield in MS. The effect of impurities in glycerol feed stream also influences with hydrogen production in APGR. Especially, methanol, which is an impurity in glycerol feed obtained from biodiesel production, significantly reduces glycerol conversion in TSSDR.