Preparation,Characterization And Reactivity Testing Of Zine Feirite Sorbents In The Lower Temperature Range (350-450℃)

The thermal efficiency for normal thermal power station usually has only 30-50% and the pollution is serious, therefore, how to utilize coal resource efficiently becomes an important task in the world. The Integrated Gasification Combined Cycle(IGCC) is considered to be one of the most promising way for high efficiency and clean utilization of coal in the 21th century and can reach around 45% of thermal efficiency. The China government has paid attention to IGCC which has been listed as the national key scientific item in China. The hot gas clean-up is regarded as a key technique in the whole IGCC process.In recent years, many researchers mainly focus on mixed solid metal-oxide sorbents for the hot gas clean-up in the world. The sorbents can remove sulfur compounds from coal gas and can be regenerated with air. Zinc ferrite sorbents are considered to be the novel sorbents, which maintains the high desulfurization efficiency of zinc oxide and the high sulfur capacity and reactivity of iron oxide.In this paper, an attempt was made to investigate preparations of zinc ferrite sorbents and effects of binders on pore volume, strength and desulfurization efficiency of zinc ferrite sorbents. Moreover, the behaviour of zinc ferrite sorbents during desulfurization and regeneration process was studied. The properties of zinc ferrite were characterized by means of conventionaltechniques, such as BET and XRD. From above all results, some useful conclusions are summarized as following:Zinc ferrite sorbents prepared by coprecipiated were identified as a novel sorbents for the hot gas clean-up, which can possess not only high desulfurization efficiency but also high sulfur capacity at 350-400 .The content of zinc ferrite in the sorbents is around 30% in order to achieve high sulfur capacity and high desulfurization efficiency. The reactivty could be improved by addition of litter starch to the zinc ferrite sorbents.Znic ferrite sorbents prepared by coprecipiated can bear the test of three cycles of desulfurization-regeneration. After three cycles, sulfur capacity and distribution of pore diameter of zinc ferrite sorbents changed slowly, but its strength increased. Above all, Zinc ferrite sorbents had good durability and high desulfurization efficiency for multi-cycle tests of desulfurization-regeneration.In brief, the zinc ferrite sorbent for the hot gas clean-up posses good properties of desulfurization and regeneration. This work is useful for developing extensively the sorbents on the industrialscale.