Heterogeneous activation of peroxymonosulfate for bisphenol A degradation using CoFe2O4 derived by hybrid cobalt-ion hexacyanoferrate nanoparticles

A facile coprecipitation-thermal method is reported to prepare spinel cobalt ferrites CoFe2O4 nanoparticles (NPs) with a well-defined mesoporous dominated structure using hybrid cobalt-ion hexacyanoferrate (CoFeHCF) NPs as a template. The properties of the synthesized catalysts are evidenced by various characterization methods. And the effects of time, pH, catalyst/oxidant/BPA dosage, coexisting ions and natural organic matter (NOM) on catalytic degradation of bisphenol A (BPA) are investigated. The as-prepared CoFe2O4 shows a high catalytic performance of 97% elimination for 45 mu M BPA in 40 min. The excellent catalytic performance could be attributed to the large specific surface area (66.18 m(2)/g) and high content of cobalt (the atomic ratio of Fe/Co is 1.86) of CoFe2O4 NPs. Slightly alkaline pH, higher catalyst dosage and anions including Cland CO32-/HCO3 are favorable for BPA degradation. Especially, 81.57% mineralization of BPA could be achieved in 60 min under the optimization system. The catalytic capacity of CoFe2O4 could be regenerated by simple washing and drying at 200 degrees C, which is much lower than the crystal temperature. SO4 center dot- and HO center dot are the primary reactive species responsible for BPA oxidation while SO4 center dot(-) might play a dominant role. This work provides a novel method to produce CoFe2O4 nanocatalysts for contaminant degradation and encourage the extended application of CoFeHCF in the environment.