| Propylene oxide (PO) is a kind of important chemical product. In China, the old PO manufacture method is chlorhydrin method ,so it will fall into disuse facing the pressure of environment because of using chlorine as raw-material and producing vast CaCl2 byproduct .The epoxidation of propylene using hydrogen peroxide as the oxidant catalyzed by TS-1 offers a clean and economically viable alternative to existing chlorhydrin method. But the oxidation of propylene to PO is one of the most challenging subjects in catalyst. Both slow rates and competing side reactions usually resulted in poor yields in metal oxide-catalyzed epoxidation with hydrogen peroxide. The invention of titanium silicalite (TS-1) opened a new route for the manufacture of PO.Titanium silicalite (TS-1) is one kind of novel type molecular sieve, appearing in 1980's. It gives new chance for the studies of the catalytic oxidizing reactions and the developing of the environment-friendly chemical engineering progress. Its application for the catalytic reaction was regarded as 1980's milestone in zeolite catalysis. Many reactions using TS-1 as the catalyst, such as the hydroxylation of phenol and the epoxidation of propylene have been investigated recently, which exhibit a vast potential application in industry. But the application of TS-1 in the industry was hindered seriously by many defects of the classical synthesis such as the high cost of the raw material, the severe preparation condition and the pinch of molding method about TS-1.In the classical synthesis of TS-1 alkali free TPAOH is used as the template and TS-1 is produced at the severe condition and high cost , which makes the synthesis difficult to be industrialized. The synthesis of cheap titanium silicalite (TS-1) using self-made TPABr as the template, silica colloidal as the silica source,n-butylamine as the base, TBOT as the titanium source was enlarged step by step. Cheap TS-1 was synthesized in a 100L autoclave high productivity and as-synthesized TS-1 exhibited high crystallinity and good performance in propylene epoxidation, which decreases the cost of TS-1 largely.In autoclave reactor, it is difficult to separate between the powder of TS-1 and the products and the process of the production is discontinuous. Thus autoclave is inapplicable to industry. Fixed-bed reactor can overcome these above shortcoming of autoclave reactor, which is applicable to industry. But TS-1 powder must be molded before it is used in fixed-bed. The molding of the powder TS-1 is one of the most important steps in the industry of propylene epoxidation.TS-1 synthesized by cheap system in 100L autoclave was used to investigate the effects on the epoxidation. Strip TS-1 catalyst was prepared using traditional extruding method of molding. Lamina TS-1 catalyst was prepared by spray molding method. Their catalytic performances were tested in fixed-bed. Effects of the molding parameters were systematically discussed. A better molding method was selected , which was fit for application of industry. As-obtained Strip or Lamina TS-1 were used to catalyze propylene into propylene oxide (PO). Effect of the reaction parameters on the epoxidation result was investigated, and the optimal reaction condition was selected. And the optimal result in lab was successfully magnified in monotube fixed-bed reactor in factory. All the above work has afforded valuable information to industrialize the application of propylene oxide (PO) from propylene and hydrogen peroxide using TS-1 as the catalyst.From the systematical studies in this paper, the following results have been obtained.1. Titanium silicalite-1 (TS-1) with different crystal size was synthesized in the system of TPABr-n-butylamine by adjusting the formation of gel and the method of crystallization. The synthesized materials were characterized by IR,XRD, SEM, UV-Vis, XRF and 27A1 MAS NMR. The effect of crystal size on epoxidation of propylene with dilute H2O2 was investigated. The results show that, when b axis of TS-1 is less than l?m,...
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