Sonochemical Treatment of Orange II Using Ultrasound at a Range of Frequencies and Powers

A range of methods are reported for the treatment of Orange II in aqueous solution with a variety of ultrasonic equipment in the absence of oxidants. The frequencies studied were 20 kHz (using a probe system) and a range of baths at 40, 380, 850, 1000 and 1176 kHz using different power inputs. Using ultrasound alone the higher frequencies were more efficient for the decolorization of Orange II. The most effective decolorization of Orange II in terms of power was achieved at 850 kHz and increased from 4.1% to 49.0% with increasing ultrasonic power from 2.04 W to 22.07 W over 2 hours. This trend was in good agreement with the corresponding production of H