Effect Of Seeding On The Low-cost Synthesis Of TS-1 Molecular Sieve

Since titanium silicalite TS-1 was successfully prepared in 1983, it has exhibited the unique catalytic performance in many selective oxidation reactions involving H2O2 as the oxidant. TS-1 has a promising perspective of industrial for the special catalytic perfor-mance under mild conditions and little pollution to the environment.In the classical synthesis of TS-1, high cost TPAOH is used as template. The repl-ace of TPAOH with TPABr in the low-cost method results in longer crystallization tim-e than the former. The micro-TS-1 was used as seeds to short the crystallization time in this paper, TS-1 combined well stability was successfully synthetized. The dependen-ce of nano-seeds in the low cost synthesis was extricated. Through the SEM technolo-gy, the guide function of crystal seeds was investigated in the low-cost method, the eff-ect of Na2SO4 and Tween 20 introduction on the catalytic performance of propylene e-poxidation was studied. The following results have been obtained:1. In the processing of micro-TS-1 seed-transferring, the TS-1 with stable performa-nance was got.2. The seeds were dissolved to crystal nucleus attached on the gel at the beginning of the synthesis of TS-1, the cumulate crystal cells were dispersed to laminal crystals aft-er the gel turned to cumulate crystal cells. Crystallization time of synthesis with seeds was shorter than that of without seeds. And TS-1 with seeds showed well catalytic perf-ormance in the propylene liquid phase epoxidation reaction.3. The introduction of Na2SO4 and Tween 20 in the phase of gel increased the sel-ectivity of PO, the conversion of H2O2 enhanced at the beginning and then fell down. TS-1 showed well catalytic performance with the molar ratio of Na2SO4 and Si is 0.1.