The sulfidation reaction kinetics of fine particles of zinc titanate and zinc oxide with H2S were studied in order to test the potential of the sorbent injection hot-gas desulfurization process. The sorbent particles with diameter between 0.3 and 60 mum were sulfide with H2S and/or reduced with H2 in a laminar flow reactor over the temperature range of 500-900 deg C. Sulfidation/reduction conversion was compared for different particle sizes and sorbents with various porosities and atomic ratios of Zn and Ti. In reduction of ZnO with H2 and without H2S, significant amount of Zn was formed and vaporized, while the presence of H2S suppressed elemental Zn formation. This suggests that H2S may suppress the surface reduction of ZnO and/or gaseous Zn may react with H2S homogeneously and form fine particles of ZnS. Formation and vaporization of elemental Zn frorn zinc titanate sorbents was slower than from zinc oxide with and without H2S.
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