Synergistic improving photo-Fenton and photo-catalytic degradation of carbamazepine over FeS2/Fe2O3/organic acid with H2O2 in-situ generation

Herein, a heterogeneous photo-Fenton and photo-catalytic system was constructed using oxide pyrite (FeS 2 /Fe 2 O 3 ) mineral and organic acids including tartaric acid (TA), ascorbic acid (AA), and citric acid (CA). In the proposed system, FeS 2 /Fe 2 O 3 can be successfully activated through irradiation to generate photogenerated carriers, which generated H 2 O 2 in-situ through the reduction reactions between e - and O 2 . The addition of organic acids enhanced the dissolution of iron from FeS 2 /Fe 2 O 3 . Based on the iron and in-situ generated H 2 O 2 , •OH was produced through a photo-Fenton reaction. Furthermore, h + , e - , and •O 2 − , which were generated through the photo-catalytic activation of FeS 2 /Fe 2 O 3 , also played a certain role in the degradation of carbamazepine (CBZ). Therefore, the synergistic photo-Fenton and photo-catalytic reaction improved the degradation of CBZ, with the degradation efficiencies of 86%, 62%, and 68% in FeS 2 /Fe 2 O 3 /TA, FeS 2 /Fe 2 O 3 /AA, and FeS 2 /Fe 2 O 3 /CA systems, respectively. This investigation provides an innovative strategy for the removal of organic pollutants using natural minerals.