Enhanced Naproxen Elimination in Water by Catalytic Ozonation Based on NiO Films

Claudia M Aguilar-Melo,Julia L Rodríguez,Isaac Chairez,Jorge Vazquez-Arenas,J A Andraca Adame,J A Galaviz-Pérez,Iván Salgado,Tatyana Poznyak

doi:10.3390/catal10080884

Abstract

This study evaluates naproxen (NP) degradation efficiency by ozonation using nickel oxide films (NiO(F)) as a catalyst. The NiO films were synthesized by chemical vapor deposition and characterized by X-ray diffraction, scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy. NP degradation was conducted for 5 min using 10 films of NiO(F) comparing against ozonation using 100 mg/L NiO powder in suspension (NiO(S)) and conventional ozonation (O3-conv). Total organic carbon analysis demonstrated a mineralization degree of 12% with O3-conv, 35% with NiO as powder and 22% with NiO(F) after 60 min of reaction. The films of NiO(F) were sequentially used 4 times in ozonation demonstrating the stability of the synthesized material, as well as its properties as a catalyst for ozonation. A proposed modeling strategy using robust parametric identification techniques allows the comparison of NP decomposition pseudo-monomolecular reaction rates.

Highlights

The growing interest in catalytic ozonation is a consequence of their remarkable advantages with respect to conventional ozonation whose benefits are (a) enhancing the recalcitrant pollutants removal in water, (b) reducing reaction period, and (c) increasing the mineralization degree [1,2]
The structural analysis was complemented with the X-ray diffraction (XRD) study
chemical vapor deposition (CVD) method allowed the synthesis of thin NiO films (240 nm thick) with relevant catalytic characteristics in NP degradation by ozone

Summary

Introduction

The growing interest in catalytic ozonation is a consequence of their remarkable advantages with respect to conventional ozonation whose benefits are (a) enhancing the recalcitrant pollutants removal in water, (b) reducing reaction period, and (c) increasing the mineralization degree [1,2]. The presence of suspended metallic oxides particles in a catalyst breaks down the ozone molecule leading to radical generation (·OH mainly). These radicals are more reactive than molecular ozone due to their higher oxidation potential [3]. Different catalysts have been used in the ozonation for decomposing a wide variety of pollutants in water, including suspended metal oxides [4], supported metal oxides [5,6], activated carbon [7], zeolites and clay minerals [8] are the most extended ones due to their fast and efficient radicals generations.

Methods

Results

Conclusion