Titanium Silicalite-1 Modified By Organic Base And Its Performance In Propylene Epoxidation

This paper used an unique Teflon lined autoclave. The unmodified TS-1 was located in the center of the autoclave and organic base solution was in the bottom. When heated, TS-1 catalyst was modified by the steam of organic base. As the autoclave cooled, TS-1 and organic base separated automatically.More importantly, the organic base could be reused. TS-1 catalysts were modified by several organic bases.The catalysts before and after treatment were characterized by XRD?FT-IR?UV-Vis?SEM and nitrogen physical adsorption.Catalytic performance of TS-1 modified were evaluated by the reaction of propylene epoxidation. The results were shown as follows:1. Compared with TS-1 unmodified, catalytic performance of TS-1 modified in propylene epoxidation were improved.Such as, XH2O2 increased significantly,but Spo reduced. Whereby, the EDA modified TS-1 had a higher catalytic activity.The XH2O2 and Spo were 95.5% and 82.3%, respectively.With the increasing EDA concentration, XH2O2 did not change significantly and Spo reduced at the same time.2. In the case of TS-1 modified by EDA, the influence of treatment time and temperature on the propylene epoxidation were investigated. The results showed that the proper condition was 48h and 170?, respectively.3. This method of modification could be applied to variety of TS-1 so that the XH2O2 of TS-1 modified with this method were improved.4. The TS-1 extrudates before and after EDA treatment were evaluated by the reaction of propylene epoxidation in a fixed-bed reactor. When the n(C3H6)/n(H2O2) was reduced from 4.5 to 3.5, the modified TS-1 also showed a well catalytic activity. Compared with TS-1 unmodified, XH2O2 increased but Spo did not change significantly at the 40? condition.