Regeneration of Zinc Titanate H₂S Sorbents

Zinc titanate is one of the leading regenerable sorbent candidates for high-temperature hydrogen sulfide (H 2 S) removal from coal gasifier gas. Temperatures in excess of 625 °C are required for regeneration of sulfided zinc titanate using air. However, hot-gas desulfurization processes require initiation of regeneration at temperatures below 550 °C. Modified zinc titanate sorbents were prepared by coprecipitation with Cu, Ni, Co, Fe, and Mo at levels up to 10 wt % to reduce the regeneration temperature. The maximum reduction in regeneration temperature was achieved for a zinc titanate sorbent with 5 wt % Co and 5 wt % Ni, which could be regenerated at temperatures as low as 475 °C.