A heterogeneous catalyst containing tetraruthenium (IV)-substituted silicotungstate: Preparation, characterization and catalytic performance toward oxidation of n-tetradecane with air

•The heterogeneous catalyst SBA-15-Apts-SiW10Ru2 was first prepared.•The oxidation of n-tetradecane was first investigated under green conditions.•SBA-15-Apts-SiW10Ru2 was first used as catalyst for oxidation of n-tetradecane.•The catalyst SBA-15-Apts-SiW10Ru2 exhibits better catalytic activity.

Developing novel catalyst with better performance for n-tetradecane oxidation under environmentally friendly conditions is being extensively pursued in both industrial and academic research. Here we report the first study on the catalytic application of a tetraruthenium (IV)-substituted silicotungstate towards the oxidation of n-tetradecane with air alone without any additives and solvents. We employed a conventional method to synthesize the polyoxoanion [{Ru4O4(OH)2(H2O)4}(γ-SiW10O36)2]10− (SiW10Ru2). Subsequently, we anchored this anion on 3-aminopropyltriethoxysilane (Apts)-modified SBA-15 to prepare a heterogeneous catalyst SBA-15-Apts-SiW10Ru2 and characterized it using powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), N2-adsorption measurements, Fourier transform infrared reflectance (FT-IR) spectroscopy and Raman spectroscopy. Finally, the catalytic performance of SBA-15-Apts-SiW10Ru2 was investigated in the oxidation of n-tetradecane under the green conditions. The result indicates that the heterogeneous catalyst SBA-15-Apts-SiW10Ru2 exhibits the enhanced catalytic activity than SiW10Ru2 itself.

Graphical abstractThe tetraruthenium (IV)-substituted silicotungstate anion [{Ru4O4(OH)2(H2O)4}(γ-SiW10O36)2]10− was anchored on 3-aminopropyltriethoxysilane-modified SBA-15 to form a heterogeneous catalyst for solvent-free aerobic oxidation of n-tetradecane with air as the oxidant under mild conditions.Figure optionsDownload full-size imageDownload as PowerPoint slide