Decolorization of a simulated wastewater using ozonation

Ozonation process is a useful procedure for industrial wastewater treatment. The aim of the present work is to investigate the ozonation treatment for the oxidation of a simulated wastewater that contains Rhodamine B. At first, wastewater containing Rhodamine B with different pHs (0.9, 3.9 and 10) and concentrations (12.5, 25 and 50) exposed to ozone gas at different times. Then, to obtain the remaining concentration of Rhodamine B in the samples, the absorption of light with a wavelength and specific energy measured using a spectrophotometer. Then, with having the absorption rate, the concentration was calculated. Based on the obtained data, an empirical correlation that shows the decolorization percent versus time is proposed. The tests showed that the decolorization rate would decrease by increasing the initial concentration of Rhodamine B from 12.5 to 50 mg/L and adding NaOH would increase the decolorization rate. Finally, it was concluded that ozonation with almost complete decolorization in a short time is an effective way for color removal from wastewaters containing Rhodamine B.

Keywords:

Ozone , Decolorization , Rhodamine B , Spectrophotometer , Empirical correlation