Mesoporous Titanium-Silica Composite Encapsulated γ-Fe2O3: Novel Magnetically Recyclable Heterogeneous Catalysts for Olefin Epoxidation Reactions

gamma-Fe2O3 microparticles encapsulated with silica and an outer layer of ordered mesoporous titanium-silica (gamma-Fe2O3@nSiO(2)@mTi-Si) were synthesized and used for the epoxidation of olefins. Characterization results showed that this material exhibits a typical core-shell structure with high surface area, narrow pore size distribution and high magnetization. Catalytic activity tests showed that this material presents high activity for the epoxidation of olefins, and the catalyst could be easily recycled and reused for several times.