Heterogeneous catalytic ozonation of ciprofloxacin in aqueous solution using a manganese-modified silicate ore.

Lisha Luo,Ming Zhou,Bingjing Xin,Dongwei Lu,Donglei Zou,Xuedong Zhai,Jun Ma

doi:10.1039/c8ra06880a

Lisha Luo, Ming Zhou + Show 5 more

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https://doi.org/10.1039/c8ra06880a

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Abstract

Manganese modified silicate ore (MnSO) prepared using an impregnation method was used as a heterogeneous ozonation catalyst, and the catalytic activity was evaluated by the degradation of ciprofloxacin (CIP). The results showed that the manganese oxide was successfully loaded onto natural silicate ore (SO). The degradation and mineralization efficiencies of CIP were considerably improved in the presence of MnSO. Under optimal conditions, the CIP removal process followed the pseudo-first-order reaction model well. The degradation rate constant of MnSO/O3 was 1.7 times and 3.3 times higher than those of SO/O3 and only O3, respectively. During the ozonation of the CIP aqueous solution in the presence of MnSO, the TOC removal rate reached 61.2% at 60 min, but was only 30.8% using ozonation alone. The addition of tert-butanol (TBA) significantly inhibited the degradation efficiency of CIP, which indicated that catalytic ozonation of MnSO followed a hydroxyl radical (·OH) reaction mechanism. Furthermore, MnSO showed great stability and durability over several reaction cycles.

Highlights

In recent years, antibiotics have been widely developed and increasingly used in the aquaculture, animal farming, and human pharmaceutical industries.[1,2] Most antibiotics enter aquatic systems and lead to chemical pollution and resistant gene pollution.[3]
Manganese modified silicate ore (MnSO) prepared using an impregnation method was used as a heterogeneous ozonation catalyst, and the catalytic activity was evaluated by the degradation of ciprofloxacin (CIP)
XRD of the SO and MnSO sample is shown in Fig. S2.† In the pattern of the SO, the diffraction peaks matched with the published XRD pattern of the cristobalite (JCPDS no. 89-3607) and a-quartz (JCPDS no. 851054)

Summary

Introduction

Antibiotics have been widely developed and increasingly used in the aquaculture, animal farming, and human pharmaceutical industries.[1,2] Most antibiotics enter aquatic systems and lead to chemical pollution and resistant gene pollution.[3]. Heterogeneous catalytic ozonation, which combines ozone with a solid catalyst, is an effective advanced oxidation technology for the degradation and mineralization of CIP.[8,9,10,11] The solid catalyst can accelerate the decomposition of ozone to hydroxyl radical ($OH) and can adsorb organic pollutants

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