Improvement of the Desulfurization and Regeneration Properties through the Control of Pore Structures of the Zn-Ti-based H_2S Removal Sorbents

摘要

To improve the sulfur removing capacity of the conventional Zn-Ti-based H_2S removal sorbents,a new Zn-Ti based sorbent(ZT-cp)was prepared by the coprecipitation method and tested in a packed bed reactor at middle temperature conditions(H_2S absorption at 480 deg C,regeneration at 580 deg C).The new Zn-Ti-based sorbent showed excellent sulfur removing capacity without deactivation,even after 10 cycles of absorption and regeneration.The conventional Zn-Ti-based sorbents(ZT-700,ZT-1000),however,that were prepared by physical mixing,were continuously deactivated.In particular,the initial sulfur removing capacity of the ZT-cp sorbent showed a very high absorption value(0.22 g S/g sorbent),which corresponded to 91.6% of theoretical absorption amount.These results can be explained by the difference in physical properties such as pore volume,surface area,and particle size.It was also found that the sulfides formed from the ZT-cp and ZT-1000 sorbents with spinel structure were easily regenerated even at 580 deg C.Those from the ZT-700 sorbent,with separated ZnO and TiO_2 structures,needed a temperature higher than 610 deg C for regeneration.