Catalytic Activity and Structure Properties of Doped VOHPO<SUB>4</SUB>·0.5H<SUB>2</SUB>O with Nanosized Ru, Au, Fe and Mn in Benzene Hydroxylation

Abstract

The promotional effect of nanosized Ru, Fe, Au, and Mn particles on VOHPO4 x 0.5H2O (VHP) catalytic properties was investigated in benzene hydroxylation reaction using hydrogen hydroperoxide (H2O2) as oxidant. Catalytic results indicated a profound effect of the nanoparticle dopants on VHP catalyst activity and products distribution. Amongst the promoted VHP catalysts, Au/VHP exhibited high catalytic effect with benzene conversion of 76% at a combined 85.5% selectivity toward the formation of phenol and hydroquinone achieved in 6 h under optimised reaction conditions. The extended scope application of nanosized doped Au-VHP showed to provide an effective catalyst for activation of the aromatic hydrocarbons C-H bonds into oxygenate derivatives. The catalyst could be re-used for several cycles with insignificant loss of activity. The doped nanosized Au-VHP catalyst provide a clean promising catalytic route based on heterogeneous catalysis for transformation of aromatics into value-added oxygenates.

Metal and Metal Oxide Nanoparticles: A Lever for C–H Functionalization

“…In particular, the doped Ru- and Au-VHP nanocatalysts displayed remarkable catalytic performance and reusability (up to 5 consecutive runs). Benzene conversion of up to 76% at 85.5% total selectivity toward the formation of phenol and hydroquinone was obtained using Au-VHP nanocatalyst …”

“…At present, commercial processes involve high temperatures, high pressures, low yields, and low selectivity. AuNPs supported on VOHPO 4 ·0.5H 2 O (VHP) were applied in cyclohexane oxidation under relatively low temperatures (70 °C), using hydrogen peroxide as the oxidant and acetonitrile as the solvent . Conversion was up to 68% with a cyclohexanol/cyclohexanone combined selectivity of 84% (cyclohexanol/cyclohexanone ratio ≈ 2:1); the nanosized catalyst could be recycled five times with negligible activity loss.…”

Synthetic utility of metal catalyzed hydrogen peroxide oxidation of C-H, C-C and C=C bonds in alkanes, arenes and alkenes: Recent advances

“…Among the promoted VHP catalysts, Au/VHP exhibited a high catalytic effect with benzene conversion of 76% at a combined 85.5% selectivity, toward the formation of phenol and hydroquinone achieved in six hours, under optimized reaction conditions. 101 Among different metal-doped graphitic carbon nitride catalysts (Cu-, Fe-, V-, Co-, and Ni-mpg-C 3 N 4 ), the vanadium-doped graphitic carbon nitride catalyst V-mpgg-C 3 N 4 was found to be the most efficient. Pyridine(Py)-modified vanadium substituted heteropoly acid (Py 3 PMo 11 V) with Keggin structure was applied for direct oxidation of benzene to phenol.…”