The combined impact of carbon type and catalyst-aided gasification process on the performance of a Direct Carbon Solid Oxide Fuel Cell

The combined impact of carbon type (anthracite coal, bituminous coal and pine charcoal) and in situ, catalyst-aided, carbon gasification process on the electrochemical performance of a Direct Carbon Fuel Cell (DCFC) is explored. The effect of operation temperature (700–800 °C) and catalyst (Co/CeO2) infusion to carbon feedstock under CO2 atmosphere at the anode chamber is systematically investigated in a cell of the type: Carbon + CO2|Cu-CeO2/YSZ/Ag|Air. All fuel samples were characterized, in terms of chemical composition, crystallite structure (XRD), pore structure (BET), surface morphology (SEM), particle size distribution (PSD) and thermogravimetric analysis (TGA), in order to obtain a close relationship between the carbon characteristics and the DCFC performance. The results reveal that in the absence of catalyst, the optimum performance is obtained for the charcoal sample (Pmax ~ 12 mW/cm2), due to its high volatile matter, oxygen content, porosity and carbon disorder as well as its low amount of impurities. Catalyst infusion to carbon feedstock results in a considerable increase in the achieved cell power density up to 225%, which is more pronounced for the less reactive coals and low temperatures. The enhanced performance obtained by infusing Co/CeO2 catalyst into carbon is ascribed to the positive effect of catalyst on the in situ carbon gasification, through the reverse Boudouard reaction (C + CO2 → 2CO), and the subsequent faster diffusion and electro-oxidation of formed CO at the anodic three-phase boundary.The authors would like to acknowledge financial support from the ERANET-MED (call identifier RQ2-2016) project “Direct Conversion of Biomass to Electricity in MED area via an Internal Catalytic Gasification Solid Oxide Fuel Cell”, which is co-funded by the following Euro-Mediterranean countries: Algeria, Cyprus, Egypt, France, Germany, Greece, Italy, Jordan, Lebanon, Malta, Morocco, Spain, Tunisia, Turkey (ERANETMED2-72-246 DB-SOFC).Peer reviewe

“An electrocatalytic membrane-assisted process for hydrogen production from H2S in black sea: Preliminary studies

Summarization: The feasibility of hydrogen production by the decomposition of H2S in an electrocatalytic membrane reactor for the exploitation of H2S contained in Black Sea water is investigated. A micro-structured electrochemical membrane reactor with a proton-conducting ceramic membrane is considered for processing gaseous H2S diluted (1 vol.%) in H2O mixtures. Y-doped barium zirconate (BaZr0.85Y0.15O3−δ) is employed as solid electrolyte. Ceria supported transition metal (Co, Ni, Fe, Cu) catalysts and LaCrO3 composites are explored as anode materials and La0.6Sr0.4Co0.2Fe0.8O3−δ perovskite type oxides are used as cathode electrodes. Preliminary results concern materials preparation and characterization of the catalytic performance of anodic electrode materials. Co/CeO2 composites show excellent H2S conversion and stability performance in wet and dry atmospheres at 873–1123 K. Presence of water has a beneficial effect on the H2 formation, in accordance with thermodynamics. The overall process starting from H2S containing sea water to H2 generation in the membrane reactor and H2SO4 production in a sequential step is simulated and its energy balance is discussed.Παρουσιάστηκε στο: 13th International Conference on Clean Energ