DECHEMA

About: DECHEMA is a nonprofit organization based out in Frankfurt am Main, Germany. It is known for research contribution in the topics: Corrosion & Oxide. The organization has 756 authors who have published 1307 publications receiving 25693 citations.

Development of a Coking‐Resistant NiSn Anode for the Direct Methane SOFC

Abstract: The present work reports on the development of a coking-resistant NiSn-based membrane electrode assembly (MEA) for internal CH4 reforming in solid oxide fuel cells (SOFCs). Catalyst powder was prepared in a centrifugal casting oven by melting stoichiometric amounts of Ni and Sn under vacuum. The formation of Ni3Sn2 intermetallic phase was confirmed by XRD analysis. Catalytic activity for CH4 reforming and stability of the NiSn powder were first evaluated in a quartz glass reactor for 4 h at 600–1,000 °C. The main reaction products H2 and CO were detected by gas chromatography while no carbon formation was detected during the experiments. Then, 3YSZ electrolyte-supported MEAs were fabricated with a Ni3Sn2/YSZ anode and LSM/YSZ cathode and characterized under SOFC conditions. The MEA showed an excellent stability under CH4 atmosphere (3% H2O) at 850 °C over more than 650 h. No substantial decrease in cell potential was observed during this period.

Oxidation behaviour of particle reinforced MoSi2 composites at temperatures up to 1700°C.

Abstract: The financial support of these investigations by the Bundesministerium fur Bildung, Wissenschaft, Forschung und Technologie (BMBF) (contract number 03 N 2015 C1) is gratefully acknowledged by the authors.

Deposition of Manganese and Cobalt on Ferritic–Martensitic Steels via Pack Cementation Process

Abstract: Heat resistant ferritic–martensitic steels are of great interest for many applications at high temperatures. The working temperature of modern solid oxide fuel cells has decreased from 1,000 to 600–800 °C, which allows the application of ferritic steels for use as interconnect materials. Another possible application is for superheaters in fossil fuel power plants. However, such environments often contain a high amount of water vapor, which is known to promote the formation of volatile chromium species CrO2(OH)2 leading to insufficient oxidation resistance of Cr-steels. Spinel phases at the surface are believed to suppress this evaporation. Reference oxide samples were prepared to investigate the kinetics of the weight changes of chromia, manganese oxide, MnCr2O4-phase and MnCo2O4-phase without the influence of the substrate material. These samples were exposure to synthetic air with 10 % water vapor at 800 °C. The results confirm that an enrichment of manganese and cobalt in the metal subsurface zone can play a beneficial role. The diffusion of these elements via pack cementation into the steel subsurface zone is presented for conditions where the bulk phase is not altered.