Easy route for the synthesis of Fe-SBA-16 at weak acidity and its catalytic activity in the oxidation of cyclohexene

Abstract

The synthesis of Fe-SBA-16 with isolated framework Fe species was achieved by simple adjustment of molar ratio of co-surfactant n-butanol, TEOS, n H 2 O / n HCl ratio, Si/Fe ratio, and aging condition, respectively. The extent of mesopore structural ordering and the coordination of iron are confirmed by X-ray diffraction, N 2 physisorption, 29Si-MAS NMR, SEM, TEM, electron spin resonance (ESR), and NH 3-TPD analysis. The material obtained constitutes micro- (∼316 m 2/g) and mesopore surface area (∼1000 m 2/g), with high-mesopore sizes (∼9.8 nm). The micropore volume present up to 0.28 cm 3/g, while the total pore volume range ∼0.90 cm 3/g at the maximum. Among various Si/Fe ratios synthesized, Fe-SBA-16 with Si/Fe ratio 19 exhibited good catalytic activity for the oxidation of cyclohexene at the optimized reaction condition.