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Photolytic degradation of dissolved compounds of 16 EPA-Listed PAHs in aqueous medium, exposed to ultraviolet/ titanium dioxide (UV-C/TiO2), xenon light/ titanium dioxide (Xe/TiO2), xenon light/ hydrogen peroxide (Xe/H2O2) and ultraviolet/ hydrogen peroxide (UV-C/H2O2) was studied. The compounds which detected above detection limit of applied analytical method and instrument include: naphthalene (Nap), acenaphthylene (Acy), acenaphthene (Ace), fluorene (Flu), fluoranthene (Fln) and pyrene (Pyr) survived. A time-course experiment (0, 1, 2, 5, 12 min) was performed to determine the fate of PAHs profile along treatments. After accomplishment of the removal process ∑6 PAHs ranked as follow: UV-C/TiO2 > Xe/TiO2 > UV-C > Xe > Xe/H2O2, and UV-C /H2O2 with estimated values of 76.38, 23.02, 22.55, 2.78, 0.00 and 0.00% of the concentration values at the beginning of the treatment, respectively. High efficiency of Xe/H2O2 treatment process (100.00%) at the end of treatment and the structure of residual PAHs which changed to the lighter compounds (2,3-ringed PAHs) before accomplishment of the removal process were proven. Generally, low resistance of Fln to all treatment conditions was observed. Total removal of Nap was considered to be a characteristic PAH compound for completion of the removal of PAHs. Mutate of parent PAH compounds and intermediates were analyzed by gas chromatography-mass spectrometry (GC-MS) and the results suggest the evaluating the toxicity of the treated water due to by-product formation concerns.

Optimization of photocatalytic degradation of two natural estrogenic compounds, estrone (E1) and 17β-estradiol (17β-E2) in aqueous medium was performed on TiO2 coated Pilkington ActivTM self-cleaning glass as a novel approach to eliminate free nano-TiO2 releasing to the intended environment after treatment. The active glass was characterized by Atomic Force Microscopy (AFM), X-ray diffraction (XRD), and Raman spectroscopy to characterize the TiO2 nanoparticles. The main purposes were mineralization of target compounds in the treated water during the photocatalytic reaction and also to investigate the oxidation by products. Response Surface Methodology (RSM) has been applied to optimize the photocatalytic degradation by changing time, pH, and light intensity as effective factors. According to the results, time was the more effective parameter. The maximum efficiency degradation was achieved in alkaline media. Due to interactive effects between variable factors, 1 mg/L aqueous solution of E1 and 17β-E2 in water was totally decomposed by TiO2 photocatalyzed reactions under UV-C irradiation of 10.08 W/m2 for 52.49 min at pH 9.42. Results of GC-MS analysis were introduced 17-deoxy Estrone and 2-Hydroxyestradiol as intermediate products for E1 and 17β-E2, respectively. All of the peaks finally disappeared after 170 min. Optimized conditions were applied for real sample of wastewater, presenting 30.40% and 56.84% in the efficiency degradation of E1 and 17β-E2, respectively.