The effect of nitrate, Fe(III) and bicarbonate on the degradation of bisphenol A by simulated solar UV-irradiation

The photoinitiated degradation of bisphenol A (BPA, 520μmol/L) was investigated using a solar simulator in the absence/presence of NO3-, Fe(III), and HCO3-. The concentrations of NO3-, Fe(III), and HCO3- were 0–160, 0–10, and 0–820μmol/L, respectively, and were chosen to simulate a natural aquatic environment. The experimental region was explored using a Box–Behnken design for three factors, extended to experimentally include all eight possible combinations of presence/absence of the factors studied. The results show that, after 7 h of irradiation, photolysis occurs only to a minimal degree (2%) in the absence of NO3- and HCO3-. Increasing the concentration of NO3- and HCO3- gives rise to up to 24% degradation after 7 h of irradiation. The concentration of Fe(III) was found to play no active role under the conditions studied. A simple linear model is given that very well describes the results obtained.