The synthesis of titanium silicalite by two methods (gas-solid isomorphous substitution of Ti4+ for Si4+ and hydrothermal crystallization synthesis), aiming at decreasing its cost, and the characterization of the prepared catalyst are presented. In the hydrothermal crystallization synthesis method of titanium silicalite-1 (TS-1), TPABr can be used to replace TPAOH and the amount of TPABr can be decreased to 0.05 (TPA+/SiO2). Organic amine cannot act as a template in the presence of TPA+. It can only regulate the basicity of the gel. The order of the template effect of different templates is as follows: TPA+>TBA+>TEA+>>organic amine. In the preparation of titanium-containing zeolite by secondary synthesis, the nature of the precursor and the preparation conditions have great influence on the incorporation of titanium into the framework. The mechanism of gas-solid isomorphous substitution is proposed, and under its guidance, we have successfully prepared Ti-ZSM-5, Ti-ZSM-11, Ti-β, and Ti-mordenite. The synthesized titanium-containing zeolites have been evaluated through catalytic hydroxylation of phenol, oxidation of styrene and epoxidation of propylene with aqueous H2O2. Results show that the Ti-containing zeolites possess high activity both in hydroxylation, styrene oxidation and in epoxidation.

The direct synthesis of para-diethylbenzene (PDEB) was achieved commercially via ethylation of ethylbenzene over EA catalysts (modified ZSM-5 zeolites). The preparations of EA catalysts by modifying micron-sized ZSM-5 zeolites and the performances of EA catalysts in industrial units are discussed. It is observed, that the PDEB selectivity of HZSM-5 can be enhanced by strengthening the channels' geometric constraints, decreasing the amount of strong acid sites and eliminating the external surface acid sites of H-type zeolites. And that with combined modifications, an all-sided adjustment of said parameters of HZSM-5 zeolites could be reached, which favors the preparation of commercial catalyst by allowing good activity and durability. Combined modifications also works well in elevating the PDEB selectivity ofnano-sized ZSM-5 zeolite, the promising candidate for a new generation ofpara-selective catalyst.

The propylene epoxidation using supported titanium silicalite TS-1 catalyst was systematically investigated in a fixed bed reactor. Different supports such as SiO2 and Al2O3 were used and two molding methods were adopted to prepare the catalyst. Strip TS-1 catalyst of 1mm

The side-chain alkylation of toluene with methanol catalyzed by the modified binary zeolite catalysts of KX and Al2O3, KX, KY, KM, or KZSM-5 has been studied. It was found that the selectives of styrene increased with the partial charge on the (A104) tetrahedra in the second zeolite component. The KX/KZSM-5 binary zeolite catalysts had much higher activities than did the separate zeolite catalysts, and the catalytic properties were greatly improved after H3BO3 and KOH modifications. Comparing the alkylation data with the t.p.d, measurements of NH3 and C02, Sanderson's electronegativity, and the partial charge on the(A104) tetrahedra, it is concluded that the side-chain alkylation of toluene with methanol on the binary zeolite catalysts is an acid-base cooperative, selective reaction.