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Abstract:High temperature H2S sorbents comprising manganese oxide (15 wt. %) supported on TiO2, ZrO2, CeO2 and Al2O3 were prepared by wet impregnation using Mn(NO3)2.4H2O as Mn precursor. Upon activation in H2, the sorbent performance testing was conducted at 650 °C in a model gas mixture with a composition of 0.4 vol. % of H2S in 40 vol. % of H2, the balance being inert gas (N2 and Ar).Sorbent regeneration was performed at 650 °C with 5.2 vol. % of O2 in N2. The initial sorption performance is first reported for the parent (Mn-free) supports showing a considerable H2S sorption on ZrO2 and CeO2 and a minor sorption on Al2O3 and TiO2. The Mn sorbents were subject to 13 sorption/regeneration cycles. The highest initial sorption capacity is reported for cerium supported Mn oxide, which is also the sample that deactivates most. A prolonged exposure to H2 at 650 °C results in a reversible loss of the sorption capacity that was observed for all the samples except for Mn on zirconia suggesting its superior stability in H2.