Research improvement in Zn-based sorbent for hot gas desulfurization

Two Zn-based sorbents, named as L-991 and L-992, used for hot gas desulfurization were developed. The L-992, which was prepared by changing Zn/Ti ratio and adding certain proportion of Cu and Mn metal oxide, has better performance than L-991. The suitable desulfurization temperature was 600–700 °C for the L-991 and 600–800 °C for the L-992. The sulfur capacity was about 16 g/100 g and 19–21 g/100 g of L-991 and L-992 respectively. After 17 multi-cycles sulfidation/regeneration tests, the sulfur capacity of the L-991 decreased greatly, while that of the L-992 still remained at 17 g/100 g. Both the sorbents showed orderly crystalline orientation and the particle size did not change. Sulfidation and regeneration tests were done both on lab micro-fixed-bed reactor and SMOVEN equipment. During the continuous tests, the H2S concentration can be reduced from about 10 g/m3 to less than 20 mg/m3, the H2S removal efficiency was > 99%.