Efficient removal of estradiol using MnFe₂O₄ microsphere and potassium persulfate complex salt

Area of Science:

• Environmental Chemistry
• Materials Science
• Catalysis

Background:

• 17β-estradiol (17β-E2) is a persistent endocrine-disrupting compound in aquatic environments.
• Effective degradation methods are crucial for mitigating 17β-E2 pollution.
• Advanced oxidation processes offer promising solutions for pollutant removal.

Purpose of the Study:

• To synthesize MnFe₂O₄ microspheres for activating potassium persulfate (Oxone).
• To investigate the degradation efficiency of 17β-E2 using the MnFe₂O₄/Oxone system.
• To elucidate the degradation mechanism and identify reactive species.

Main Methods:

• Synthesis of MnFe₂O₄ microspheres.
• Characterization using XRD, XPS, and SEM-EDS.
• Degradation experiments with varying conditions (temperature, concentration, dosage, pH).
• Free radical quenching and electron paramagnetic resonance (EPR) analysis.

Main Results:

• MnFe₂O₄ microspheres effectively activated Oxone for 17β-E2 degradation.
• Pseudo-first-order kinetics described the degradation process.
• Optimal conditions yielded 82.9% 17β-E2 removal within 30 minutes.
• Sulfate radicals (SO₄^-•) were identified as the primary reactive oxygen species (ROS).
• The catalyst showed a 24.1% decrease in efficiency after four cycles.

Conclusions:

• MnFe₂O₄/Oxone is an efficient system for 17β-E2 degradation.
• The mechanism involves heterogeneous phase activation producing sulfate radicals.
• Further research is needed to improve catalyst stability for practical applications.