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• CuFe 2 O 4 was uniformly anchored on kaolinite to activate peroxymonosulfate (PMS). • Sulfate radicals are the primary radical species in CuFe 2 O 4 /kaolinite/PMS system. • CuFe 2 O 4 /kaolinite exhibited high catalytic activity and low leaching of metal ions. • More hydroxyl groups and accessible reactive sites enhanced its catalytic activity. • Low leaching of metal is ascribed to Fe O Al bond between CuFe 2 O 4 and kaolinite. In this study, CuFe 2 O 4 /kaolinite catalysts were fabricated through a facile citrate combustion method and were evaluated for their efficiency to activate peroxymonosulfate (PMS) towards the destruction of bisphenol A (BPA). The prepared catalysts were systematically characterized to explore the relationship between their characteristics and catalytic activities. In general, higher specific surface area, larger pore volume, more hydroxyl groups, and more accessible reactive sites of 40%-CuFe 2 O 4 /kaolinite contributed to the greater catalytic activity in peroxymonosulfate activation for BPA degradation compared to bare CuFe 2 O 4. Monodispersed CuFe 2 O 4 nanoparticles were uniformly anchored on the surface of kaolinite with Fe O Al bond, which prevented leaching of metal ions and contributed to the excellent reusability. The sulfate radicals produced in the CuFe 2 O 4 /kaolinite/PMS system were proved as the predominant radical species through electron spin resonance (ESR) and radical quenching experiments. Based on the results of X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance – Fourier transform infrared spectra (ATR-FTIR), two main possible pathways of sulfate radicals generation were proposed: the generation and decomposition of Cu(II)-(HO)OSO 3 − (Cu(II)/Cu(III) and Cu(III)/Cu(II) redox reaction) and the oxidation of Fe(II). Moreover, the BPA degradation pathway was proposed through the identification of transformation products. This work provides an interesting insight for PMS activation by the high-efficient natural mineral-based catalysts for wastewater reclamation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel γ-FeOOH/g-C 3 N 4 /kaolinite composite was fabricated via two-step strategy. • Efficient electron transfer induced by γ-FeOOH and N vacancies promote the separation and migration of photo-generated carriers. • γ-FeOOH/g-C 3 N 4 /kaolinite catalyst possessed good bisphenol A removal efficiency. • The potential synergistic enhancement mechanism was well proposed. A novel ternary composite with the flower-like structure was synthesized by integrating of γ-FeOOH and g-C 3 N 4 /kaolinite containing N vacancies (FNGK). The FNGK-10 composite exhibited the superiority of bisphenol A (BPA) degradation in the presence of peroxymonosulfate (PMS) under the visible-light irradiation with the outstanding reusability and universal applicability, in which the degradation rate constant of FNGK-10/PMS/Vis system was about 3.25 and 8.42 times higher than that of FNGK-10/PMS and FNGK-10/Vis system, respectively. Moreover, the introduction of kaolinite leads to the accelerated consumption of PMS. The FTIR, EPR and XPS spectra proved that the formation of Fe-N and cyano (C≡N) bonds induced the enhancement of the efficiency of electron transfer. The photo-generated carriers could be trapped by N vacancies and γ-FeOOH, which was favorable for the separation potency of photoexcited charge carriers and reduction efficiency of Fe(III) to Fe(II). This paper gave a new perspective on the coupling application of PMS activation and photocatalytic technology to efficiently degrade organic contaminants. [ABSTRACT FROM AUTHOR]