Thermal Decomposition of H₂S at Low Temperature on Mo-Containing Catalysts Derived from MAlO (M = Mg, Co, and Ni) Layered Double Hydroxides

Abstract

It is increasingly attractive to simultaneously recover the resources of hydrogen and sulfur by catalytic decomposition of hydrogen sulfide (H 2 S). Restricted by the low yield and high reaction temperature, searching for materials with excellent catalytic activity and stability on thermal decomposition of H 2 S is significant. A high dispersion and sulfidation degree of MoS 2 phases with a promoter (Co or Ni) were prepared with the help of interaction between the layers of hydroxides (CoAl or NiAl) and Mo anions. The NiAlMo-s catalysts exhibited outstanding catalytic activity at 500 °C with H 2 yield reaching 49.6%. Several characterizations verified that the excellent performance resulted from the Lewis acid on the surface. Accumulation of sulfides reduced stability, while generation of NiMoS contributed to good stability. Generally, these results will be beneficial to enrich the theory of designing H 2 S decomposition catalysts. Also, these findings will offer potential application of the resource recovery technology on H 2 S decomposition.