Kinetics of Ozone Oxidation of Acid Red 131 Monoazo Dye in Aqueous Solution

Abstract

The synthetic dye solution of Acid Red 131 monoazo dye was ozonated in a semibatch reactor. The effect of ozone dose, initial dye concentration in the solution, and solution pH on the rate of decolorization was studied and the results were analyzed in terms of color-removal efficiency (CRE), which was found to increase with an increase in the ozone dose. Alkaline pH of the synthetic solution was found suitable for ozonation and 100% CRE was obtained after 23 min of ozone treatment at pH 11. The CRE was found to decrease with an increase in initial dye concentration of the synthetic dye solution, but the quantity of the dye removal was greater at higher concentrations. The results of decolorization kinetic research showed that ozonation of the reactive dye were a pseudo-first-order reaction with respect to the dye concentration in the solution. Experiments were performed to remove dye from the textile industry effluent by oxidation with ozone and 100% CRE was obtained. The quantities of ozone and power consumption were determined.