Supported PdSn catalysts are highly effective for the direct synthesis of hydrogen peroxide showing significantly higher selectivity to comparable PdAu catalysts.
The oxidation of cyclohexane via the in-situ production of H2O2 from molecular H2 and O2 offers an attractive route to the current industrial means of producing cyclohexanone and cyclohexanol (KA oil), key materials in the production of Nylon. The in-situ route has the potential to overcome the significant economic and environmental concerns associated with the use of commercial H2O2, while also allowing for the use of far lower reaction temperatures than those typical of the purely aerobic route to KA oil. Herein we demonstrate the efficacy of a series of bi-functional Pd-based catalysts, which offer appreciable concentrations of KA oil, under conditions where limited activity is observed using O2 alone. In particular the introduction of V into a supported Pd catalyst is seen to improve KA oil concentration by an order of magnitude, compared to the Pd-only analogue. In particular we ascribe this improvement in catalytic performance to the development of Pd domains of mixed oxidation state upon V incorporation as evidenced through X-ray photoelectron spectroscopy.
The oxidation of cyclohexane via the in-situ production of H2O2 from molecular H2 and O2 offers an attractive route to the current industrial means of producing cyclohexanone and cyclohexanol (KA oil), both key materials in the production of Nylon. Herein we demonstrate that through the in-situ production of H2O2 supported AuPd nanoparticles catalyse the formation of KA oil under conditions where activity is limited when using molecular O2, with no loss in catalytic activity observed upon re-use. The effect of key reaction parameters, including reaction temperature, catalyst mass and H2:O2 ratio are evaluated.