Preparation of Cu-Ce@γ-Al2O3 and Study on Catalytic Ozone Oxidation for the Treatment of RO Concentrate Water

Abstract

In this paper, a high-efficiency and stable Cu-Ce@γ-Al2O3 catalyst was prepared by taking the reverse osmosis (RO) concentrated water of a sewage treatment plant as the treatment object and activated alumina as the carrier. The preparation factors that affected the catalytic activity of Cu-Ce@γ-Al2O3 were investigated. SEM, EDS, XRD, BET, XRF, and XPS techniques were applied to characterize the catalyst. Optimal working conditions, and degradation mechanism of RO concentrated water were researched. In comparison with the ozone oxidation alone, the Cu-Ce@γ-Al2O3 catalytic ozonation has more reactive groups, significantly improving the treatment effect. Characterization results show that Cu and Ce are successfully supported on the surface of the activated alumina support and mainly exist in the form of oxides (e.g., CuO and CeO2). The loading of metal led to a larger specific surface area and pore volume. The repeated use had an insignificant effect on the peaks of Cu2p and Ce3d energy spectra and caused a small loss of active components. Under these conditions, the removal rate of COD from RO concentrated water by Cu-Ce@γ-Al2O3 catalyst was 85.2%. The stability and salt tolerance of Cu-Ce@γ-Al2O3 catalysts were investigated by catalyst wear rate and repeated use times, respectively. The degradation of organic matter and residual tryptophan-like organic compounds were observed through UV absorption spectroscopy and 3D-EEM. Hydroxyl radicals participated in organic pollutants degradation. Finally, a multi-level-fuzzy analysis evaluation model was developed to quantitatively assess the catalytic ozone oxidation system of the Cu-Ce @γ-Al2O3 catalyst for the treatment of RO concentrated water.

Preparation of catalyst of cobalt‐ and/or iron‐doped strontium zirconate and its performance in removal of m‐cresol using ozone as oxidant

“…4 AOPs show faster removal rates and the potential to completely remove pollutants, with superiority in treating refractory organic compounds. [5][6][7][8] AOPs, including the Fenton method, 5 photocatalytic method, 9,10 and ozone oxidation method, [11][12][13] have been applied to treat m-cresol in wastewater. The Fenton method is a homogeneous catalytic treatment method that uses hydrogen peroxide or persulfate as an oxidant and ferrous salt as a catalyst.…”

“…11 Compared with single ozone treatment, ozone catalytic oxidation can quickly produce reactive oxygen species during the reaction process, thereby more effectively degrading water pollutants. 12 Compared with homogeneous ozone catalytic oxidation, the heterogeneous ozone catalytic oxidation method avoids the problems of waste of resources and secondary pollution, which limit the application of the homogeneous ozone catalytic oxidation method in practical water treatment. [11][12][13] At present, the heterogeneous catalysts mainly include transition metals and their oxides, rare earth metal oxides, and composite oxides.…”

“…12 Compared with homogeneous ozone catalytic oxidation, the heterogeneous ozone catalytic oxidation method avoids the problems of waste of resources and secondary pollution, which limit the application of the homogeneous ozone catalytic oxidation method in practical water treatment. [11][12][13] At present, the heterogeneous catalysts mainly include transition metals and their oxides, rare earth metal oxides, and composite oxides. 14,15 Perovskites are a type of composite metal oxide with unique physical structures.…”

“…AOPs, including the Fenton method, 5 photocatalytic method, 9,10 and ozone oxidation method, 11‐13 have been applied to treat m ‐cresol in wastewater. The Fenton method is a homogeneous catalytic treatment method that uses hydrogen peroxide or persulfate as an oxidant and ferrous salt as a catalyst.…”

The Effect of Magnetic Composites (γ-Al2O3/TiO2/γ-Fe2O3) as Ozone Catalysts in Wastewater Treatment

“…Certain precious metals have been shown to have the best effect, but it has also been found that the transition metals (Mn, Fe, Cu and Zn) [ 17 ], although not producing the best effect, still produce a good effect compared with many other metals, and transition metals are easily obtained [ 18 ]. Since many metal oxides can effectively decompose ozone in the gas and water phases, many researchers have considered the application of activated alumina-supported metal oxide catalysts in the field of wastewater treatment [ 19 , 20 ]. The improvement in catalytic ozonation efficiency is mainly due to the increase in hydroxyl radicals in the ozonation reaction [ 21 ].…”