Catalytic ozonation of di-n-butyl phthalate degradation using manganese ferrite/reduced graphene oxide nanofiber as catalyst in the water.

Graphene oxide doping MnFe2O4 (rGO-MnFe2O4) nanofibers were synthesized via electrospinning method and applied to degrade refractory Di-n-butyl Phthalate (DBP) by catalytic ozonation in the water. Characterizations and effect of various conditions on DBP removal were investigated. Meanwhile, the mechanism of enhanced DBP degradation after rGO incorporation was explored intensively. Results showed that 5 wt% GO doping into MnFe2O4 improved the concentration of surface hydroxyl sites (SHSC), the oxidation potential, material diffusion and charge electronic transfer ability in contrast to MnFe2O4 nanofibers, resulting in significantly enhanced DBP degradation compared with ozonation alone. Chemisorbed oxygen groups (MnOH, COH or COOH) on the surface of rGO-MnFe2O4 played a key role in generating radicals, which was the origin of catalytic ozonation reaction. Moreover, a good positive linear relation between SHSC and DBP removal was found. The electrons cycle between Mn2+ and Mn3+ induced the ozone decomposition to produce hydroxyl radicals, which was the major impetus for DBP degradation in 5%rGO-MnFe2O4/O3 system. Composite nanofiber of 5%rGO-MnFe2O4 had a good stability and removal rate only decreased for 4% after five times reuse.