TS-1分子筛的合成及其催化丙烯环氧化反应工艺条件的优化

以纳米硅分子筛(S-1)悬浮液为晶种，在水热体系中合成TS-1分子筛。经过碱后处理和成型，得到成型的TS-1分子筛催化剂。通过XRD、ICP和XPS等表征手段研究了催化剂的性能。采用固定床反应器考察了该催化剂对低n(CH3OH)/n(H2O2)比下丙烯环氧化反应的条件及运行稳定性的影响。结果表明：经过碱后处理的TS-1分子筛表面具有较好的疏水性，且成型前后催化剂的性能不变，进而成型的碱后处理TS-1分子筛，在n(CH3OH)/n(H2O2)=4.9、反应温度为43℃、丙烯的质量空速为0.64 h-1、反应液pH值为9.10、n(C3H6)/n(H2O2)=2.1的条件下，H2O2的转化率和有效利用率均达到98%，并且此反应过程连续稳定的运行超过了1700 h。

Synthesis of TS-1 Zeolite and Its Optimal Catalytic Conditions for Propylene Epoxidation

TS-1 zeolite was synthesized with using nanosized S-1 suspension as the seed in a hydrothermal system. Then, the extruded TS-1 zeolite was obtained after alkali post-treatment and molding, and the prepared catalyst performance were further studied by different characterization techniques including XRD, ICP, XPS. In addition, with using a fixed-bed reactor, propylene epoxidation with using the prepared TS-1 catalyst under low molar ratio of methanol and hydrogen peroxide was investigated. Experimental results showed that the alkali-treated catalyst surface has good hydrophobicity, and catalyst performance did not change before and after molding. Under the reaction conditions of n(CH3OH)/n(H2O2)=4.9, temperature 43 ℃, propylene MHSV 0.64 h-1, pH value of reaction solution 9.10 and n(C3H6)/n(H2O2)=21, the conversion and utilization of H2O2 both could reach 98%. Especially, this catalyst demonstrated excellent stability during over 1700 hours test time.