The mixture was then stirred
at 35 °C for 2 h, and distilled water (920 mL) was added The mixture was then stirred
at 35 °C for 2 h, and distilled water (920 mL) was added. In
15 min, the reaction was terminated by the addition of a large
amount of distilled water (2.8 L) and 30% H2O2 solution (50
mL), after which the color of the mixture changed to bright
yellow.