Efficient catalytic degradation of bisphenol A by novel Fe0- vermiculite composite in photo-Fenton system: Mechanism and effect of iron oxide shell

Novel Fe 0 -vermiculite (Fe-Ver-C-H 2 ) composite was synthesized by thermal reduction and acted as catalysts to remove bisphenol A (BPA) in photo-Fenton system. In term of activation ability toward H 2 O 2 , separation ability and stability, Fe-Ver-C-H 2 presented obvious advantages over other kinds of Fe 0 -vermiculite composite (Fe-Ver-NaBH 4 ), which obtained by traditional liquid reduction. The reason was that iron oxide shells on the surface of Fe 0 were α-Fe 2 O 3 and Fe 3 O 4 for Fe-Ver-NaBH 4 and Fe-Ver-C-H 2 , respectively. And for Fe-Ver-C-H 2 , the synergistic effect between iron core (Fe 0 ) and iron oxide shell (Fe 3 O 4 ) is beneficial to catalytic performance. The mechanism and plausible pathway of BPA degradation were also proposed according to the results of radical scavenger studies and gas chromatography-mass spectrometry (GC-MS), respectively. In addition, factorial effects for Fe-Ver-C-H 2 in photo-Fenton system were also investigated and optimized as: pH of 5, dosage of 0.2 g L −1 and H 2 O 2 concentration of 20 mM. This study presented a facile method to synthesize novel Fe 0 -vermiculite composite and provided a new sight to investigate the effect of iron oxide shell on the catalytic performance when Fe 0 -vermiculite composite acted as catalyst to remove contaminants from the environment in photo-Fenton system.