| TS-1 zeolite with Ti(JV) in the framework of silicalite is a new kind of zeolite catalyst developed in 1980s. It was found that TS-l has unique catalytic properties. It can activate aqueous hydrogen peroxide to oxide many organic compounds selectively. These oxidation reactions carried out at ambient conditions (near room temperature) with little byproducts. The titanium silicalite catalysts have attracted much attention and many environment-friendly selective-oxidation processes have been developed based on TS-l-H202 oxidation system. Propylene epoxidation on IS-i was an environment-friendly selective-oxidation process and became one of the hotspot in the field of catalyst. The powder of IS-i exhibited good performance in propylene epoxidation in intermission reactor. (Reaction condition: temperature 3 33K; time 1 .5h; H202 O.741mo1扡; propylene pressure O.4MPa; catalyst li.9g/L; solvent methanol. Reaction result: X H202 97.4%, U H202=94.6%, S P0 =92.4%.) .But it is difficult to separate between the powder of TS-i and the products and the process of the production is discontinuous. This process is inapplicable to industry. The molding of the powder TS-i is one of the most important steps in the industry of propylene epoxidation. Strip TS-l was prepared using traditional extruding method of molding. On strip TS- 1, the effect of the reaction condition and the condition of impregnation with Na2SO4 was studied. Besides, the lamina TS-i catalyst, a new kind of molding TS-l having good performance in propylene epoxidation was exploited. And the performance of lamina TS-l treated with acid was studied. The experiment and the result were as following: 1.. The effect of the reaction condition of propylene epoxidation on strip IS-i was studied and the best reaction condition was that under 4Q0 C, the ratio between H202 and CH3OH is 1 :80(mol), the ratio between H202 and C3H6 is 1:4 and the quantity of liquid raw material is 6mIIhr.Under this condition, X 11202= 88.9%, U 11202=86.5%, S P0=44.5%. 2.. On strip IS-i, the condition of impregnation with Na2SO4 was studied. Impregnated by 0.imolJL Na2SO4 under 200 C for 8hr and then dried under 200 C, the catalyst has good performance in propylene epoxidation. Compared with strip IS-i, the selectivity of propane oxide of this kind of impregnated IS-i raised 20%. 3.. Lamina IS-I was male by spraying the IS-i on the support which was a small inert ball about 2mm diameter and the lamina was just about 0.1mm. Because of the good diffusibility of Lamina TS-1 for raw material and products, the process of deep oxidation of propane oxide was difficult to take place. At the same time, propylene epoxidation is an exothermic reaction, which is a negative effect on the selectivity of propane oxide. The support in laniina IS-i is a good radiator and it will prevent the increase of the temperature in catalyst bed. Thus, the selectivity of propane oxide was much higher than strip IS-i. From this aspect, laniina IS-i is a kind of promising catalyst in propylene epoxidation. 4.. Treated with acid, the distribution of acid of the zeolite can be changed. Simultaneity, some metal ion was delete from the catalyst. Compared with strip IS-i and lamina TS-1, the selectivity of propane oxide catalyzed by acid-treated strip IS-i and lamina IS-i reduced 36% and 46.6% respectively. Thus, acid-treated IS-i has a negative effect on propylene epoxidation.
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