Improved Catalytic Performance for 1-Butene Epoxidation over Titanium Silicalite-1 Extrudates by Using SBA-15 or Carborundum as Additives

A nanosized titanium silicalite-1 (TS-1) was synthesized in a tetrapropylammonium hydroxide hydrothermal system and was then extruded with silica and different additives (carborundum and SBA-1.5). The obtained TS-1 extrudates were characterized and evaluated in the epoxidation of 1-butene in a fixed-bed reactor. The catalytic performances are enhanced when carborundum and SBA-15 are introduced to the shaped catalysts, especially when using carborundum. The reasons for the deactivation of TS-1 and improvement of catalytic performance were studied. The mesopores in SBA-15 improve the diffusion property of substrates, leading to a higher catalytic activity. The high heat conductivity property of carborundum removes the exothermal rapidly, eliminating the side reactions and resulting in a higher stability.