Enhancement of the advanced Fenton process by ultrasound for decolorisation of real textile wastewater

Successful decolorisation of real textile wastewater was achieved by means of the advanced Fenton process in conjunction with ultrasound technology. A synergy factor of 6.9 for this combined method was determined. The decolorisation followed zero-order kinetics, and the rate increased with increasing zero-valent iron dose and decreasing pH and hydrogen peroxide concentration. The optimum conditions for an American Dye Manufacturers Institute decolorisation value of 1638 ADMI was found to be a pH of 3.0, an ultrasound frequency of 47kHz, a zero-valent iron dose of 1.0g l(-1), and a hydrogen peroxide concentration of 1.03x10(-2)m. Under these conditions, the estimated operating cost to decolorise 96% true colour was estimated to be $US 4.51m(-3). The study demonstrated that the given combined method could be applied to decolorise textile wastewaters.