| 초록 |
The regeneration properties of Znic-Titanum sorbents(ZT) calcined at different temperatures were measured fixed bed reactor at middle temperature(Sulfidation;480oC, regeneration;580oC). The sorbents treated at higher temperature than 1000oC showed a spinel crystal structure by XRD, while those treated lower than 700oC showed a separated ZnO and TiO2 with rutile crystal structure. They showed also different regeneration properties. The ZnS produced from the spinel structure during sulfidation was easily regenerated even at 580oC, while that from the separated ZnO and TiO2(rutile) needed a temperature higher than 610oC for regeneration. This difference was not changed by repeated cyclic absorption-regeneration experiment, and the initial crystal structures of both sorbents were restored. These results were explained by the difference in reactivities of ZnS with different crystal structures. In addition, anatase form of TiO2 with octahedral structure, of which structure was same with the TiO2 presented in Zn2TiO4 of spinel structure. While only rutile structure of TiO2 was formed from the separated ZnO and TiO2(rutile) sorbent. To study these differences further, FT-IR, FT-Raman, TPD and TPR were used and their results were discussed. |
