Effluent from a cow breeding base was remediated via a catalytic ozonation process that used Mn–Fe–Ce/γ-Al2O3 as the catalyst, which was prepared by the impregnation roasting method. The catalyst was found to significantly influence the treatment effects for hydroxyl radical generation. HO• generation was qualitatively and quantitatively investigated using 5,5-dimethyl-1-pyrroline-n-oxide (DMPO) reagent, electron paramagnetic resonance (EPR), and coumarin fluorescence techniques, and scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM–EDX), Brunauer–Emmett–Teller (BET) method, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) tests were performed to illustrate the structure and physical chemistry properties of the catalyst. The results showed that the modified Mn–Fe–Ce/γ-Al2O3 ternary catalyst has excellent catalytic performance and that the introduction of Mn, Fe, and Ce promotes the formation of abundant oxygen defects on the catalyst surface, which is assumed to be responsible for HO• generation. The conversion of Ce­(III)/Ce­(IV) and electron transfer/ejection due to the substitution of Ce­(III)/Ce­(IV) for Mn­(II)/Fe­(II)/Fe­(III) were considered the fundamental intrinsic reasons underlying oxygen defect formation. In addition, the conditions for HO• quenching in the system were studied with the reaction time and catalyst dosage as parameters. The results supply a new technique for treatment of dairy farming wastewater and offer guidance for understanding the reaction mechanism of ternary supporting transition-metal catalysts.

This study examines the specific effect of Tween 80 on the conversion of anthracene (ANT) in laccase medium system regarding surfactant chemical changes and mechanism. The conversion rate and degradation products of ANT were investigated in different concentrations of Tween 80 solution. Between Tween 80 concentration 0–40 critical micelle concentrations (CMC), the kinetic parameter-k (h−1) and corresponding half-life T1/2 decreased with increasing concentration. When Tween 80 was above 20 CMC the laccase-medium system converted > 95% of ANT to anthraquinone within 12 h. During the entire enzymatic reaction, the laccase activity in the system increased with increasing Tween 80 concentration. Combined with GC/MS analysis of the product, it was speculated that hydrogens belonging to the ether-oxygen bond and carbon–carbon double bond α-CH of Tween 80, were removed by the laccase-media system, promoting its degradation. Additionally, enhanced activity caused by oxygen free radicals (ROS) such as RO• and ROO•, continuously oxidized Tween 80, which in turn produced free radicals while converting ANT. This study provides new theoretical support toward the application of surfactants in the elimination of polycyclic aromatic hydrocarbons.