Solar light-induced photocatalytic degradation of methylparaben by g-C3N4 in different water matrices

BACKGROUND In this study, graphitic carbon nitride (g-C3N4) photocatalyst was successfully synthesized via calcination of urea under argon flow and tested for methyl paraben (MeP) degradation in aqueous media under simulated solar light for the first time. Its structural, morphological, and optical properties were investigated with the use of X-Ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), and Brunauer-Emmett-Teller (BET) surface area analysis method. RESULTS The as-synthesized g-C(3)N(4)exhibited high photocatalytic performance towards the degradation of MeP in ultra-pure water (UPW), yielding a near-complete elimination after 90 min of irradiation. Experimental results revealed that the photocatalytic reaction followed pseudo-first-order kinetics. Furthermore, the photocatalytic degradation of MeP was found to be strongly pH-dependent. Experiments in real water matrices (bottled water (BW) and wastewater (WW)), as well as in UPW, spiked with inorganic and organic additives (bicarbonate ions, humic acid) affected the target compound degradation. For instance, the apparent rate constant of MeP in UPW was approximately 4 and 8 times greater than that of BW and WW, respectively. The addition of persulfate ions in the reaction mixture enhanced the performance of the present photocatalytic system. Trapping experiments revealed that photogenerated holes play a leading role in the photocatalytic degradation of MeP. CONCLUSION Our findings demonstrate that g-C(3)N(4)photocatalysis can be used as an efficient technology for the removal of hazardous organic micropollutants, such as parabens. (c) 2020 Society of Chemical Industry (SCI)