Ferrite-based catalysts for peroxymonosulfate activation: comparative study of RB KN-R degradation

Ferrite-based catalysts are promising for enhancing peroxymonosulfate (PMS) activation to degrade refractory organic pollutants such as synthetic dyes. This study evaluated the catalytic performance of CuFe 2 O 4 , CoFe 2 O 4 , ZnFe 2 O 4 , MnFe 2 O 4 , and NiFe 2 O 4 for reactive brilliant blue KN-R degradation. The novelty of this work lies in CuFe 2 O 4 ’s use as a superior PMS activator, leveraging Cu 2+ /Cu + and Fe³ + /Fe 2+ redox cycling to enhance SO 4 • − generation, offering superior efficiency, cost-effectiveness, and catalyst recovery. CuFe 2 O 4 demonstrated the highest degradation efficiency (99.10%) within 5 min under optimized conditions (catalyst dosage: 50 mg/L, PMS: 400 mg/L, dye: 120 mg/L, pH: 6.4, and temperature: 25°C), supported by the highest rate constant (k = 0.9512 min −1 ). Comparative results showed CoFe 2 O 4 , MnFe 2 O 4 , ZnFe 2 O 4 , and NiFe 2 O 4 achieving lower efficiencies of 82.00%, 67.31%, 43.80%, and 16.57%, respectively. Characterization (X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy) confirmed the structural and surface properties driving CuFe 2 O 4 ’s performance, including its stability and reusability, maintaining over 90% activity after five cycles. This study establishes CuFe 2 O 4 as a highly efficient, scalable, and sustainable catalyst for PMS activation, offering a promising solution for wastewater treatment and environmental remediation.