Nano gold catalyst preparation and it’s <italic>p</italic>-nitrophenol catalytic degradation properties.

<italic>Cacumen platyclade</italic> extracts were utilized as the reducing agent to prepare Au/Al2O3 composites. XRD, BET, SEM, TEM were employed to characterize the properties of the catalyst. The catalytic activity of Au/Al2O3 was studied by using NaBH4 as the reducing agent and nitrophenol as the pollutant. The results showed that the Au/Al2O3 catalyst, calcinated at 400 °C, exhibited the highest catalytic activity. With a catalyst dosage of 1 g L−1, 2 mL NaBH4 of 0.15 mol L−1 could degrade 96.5 % nitrophenol in 21 min at 298 K, with a reaction constant of 0.16 min−1. Furthermore, the <italic>p</italic>-nitrophenol degradation ratio decreased by 0.8 % after ten cycles. [ABSTRACT FROM AUTHOR]