Photodegradation of Rhodamine B in Fe(III) Solutions

The effects of initial pH, Fe3+ and humic acid concentrations on the photodegradation of rhodamine B in Fe3+-containing solutions were studied. The distribution of Fe2+ photoformed in irradiated Fe3+ solution was studied to understand the significance of iron cycling on the removal of rhodamine B. pH has a great influence on the decolorization of dye and the process was most effective when the pH is 3.03. Increasing the dosage of ion (Fe3+) can improve the removal efficiency of rhodamine B. 99.6% of rhodamine B was photodegraded within one hour with a 6 mmol·L–1 of Fe3+. Addition of a certain dose of humic acid can facilitate the degradation of dyes and the photoformation of Fe2+.