Selective oxidation of H2S to elemental sulfur over Ce-V mixed oxide and CeO2 catalysts prepared by the complexation technique

Date

2006-09-30

Author

Yasyerli, Sena
Dogu, Gulsen
Doğu, Timur

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Selective oxidation of H2S to elemental sulfur was investigated in a fixed bed reactor using Ce-V mixed oxides and cerium oxide (CeO2) catalytic materials prepared by the complexation technique. The Ce-V mixed oxide with a V/Ce atomic ratio of one and with the CeVO4 crystal structure gave very high sulfur selectivity values (close to one) at almost complete conversion of H2S, for O-2/H2S mote ratios close to 0.5. Best operation temperature was found as 250 degrees C with this catalyst. CeO2 gave lower selectivities, causing the formation of some SO2, even at substoichiometric O-2/H2S feed ratios. It also showed a fast deactivation due to the partial sulfidation of the catalyst surface during the reaction. XPS analysis of the fresh and the used catalysts containing different V/Ce ratios strongly indicated that the selective oxidation of H2S to elemental sulfur over the Ce-V mixed oxides involved a redox cycle of cerium, rather than a redox cycle of vanadium.

Subject Keywords

H2S, Selective oxidation, Ceria, CeVO4, Claus process, XPS

URI

https://hdl.handle.net/11511/31980

Journal

CATALYSIS TODAY

DOI

https://doi.org/10.1016/j.cattod.2006.05.030

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

S. Yasyerli, G. Dogu, and T. Doğu, “Selective oxidation of H2S to elemental sulfur over Ce-V mixed oxide and CeO2 catalysts prepared by the complexation technique,” CATALYSIS TODAY, pp. 271–278, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31980.