Preparation and Characterization of Cu-Mn-Ce@γ-Al2O3 to Catalyze Ozonation in Coal Chemical Wastewater-Biotreated Effluent

Abstract

Cu-Mn-Ce@γ-Al2O3 was prepared by incipient wetness impregnation and used to catalyze ozonation in a coal chemical wastewater-biotreated effluent. The preparation factors that considerably affected the catalytic performance of Cu-Mn-Ce@γ-Al2O3, specifically metal oxide loading percentage, calcination temperature, and calcination time, were examined. The catalyst was characterized by scanning electron microscopy, energy dispersive spectrometry, X-ray diffraction, and Brunauer-Emmett-Teller analysis. The optimal catalytic ozonation operating parameters, such as ozone dosage, catalyst dosage, pH, and reaction time, were also investigated. Results showed that an optimized catalyst consisted of 17.0% CuO, 3.0% MnO2, and 2.0% CeO2 (wt.%). The optimal calcination temperature and calcination time were 600 °C and 5 h. The optimal catalytic ozonation operating parameters, including ozone dosage, catalyst dosage, pH, and reaction time, were 7, 80.0 mg/L, 20.0 mg/L, 7 and 50 min, respectively. The COD removal of biotreated effluent increased to 61% under these optimal operating conditions. Meanwhile, ozonation alone resulted in only 20% removal. This work proposes the use of easily available Cu-Mn-Ce@γ-Al2O3 catalyst and might drive the advancement of catalytic ozonation for chemical wastewater purification.

Combining ozone and ultrasound technology to remove S2− in Bayer liquor

“…Namely, O 3 as an oxidant, reacts with sulfur directly and rapidly with acidic conditions. While, O 3 is induced by the hydroxide ions in alkaline conditions to produce hydroxyl free radicals and other active radical [26] , [27] . The decomposition of O 3 in the alkaline system produces a series of chain reactions and active radical formation reactions, as shown in Eqs.…”

Metals as Catalysts for Ozonation

“…The heterogeneous catalytic ozonation uses solid catalysts (e.g., metal oxides and metals on supports). There are two ways for O 3 to be decomposed in this system: at the catalyst surface and/or react with organics adsorbed on the catalyst surface to produce HO • [41][42][43]. Many noble metals and metal oxides, immobilized or not on supports, have been used for heterogeneous catalytic ozonation [44,45], being the order of catalytic activity for the decomposition of ozone following one [46]:…”

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

“…To further improve the catalytic effect, γ-Al 2 O 3 has been used as a carrier to load some metal oxides, and its catalytic effect on ozone has been studied [ 11 , 12 ]. Among these, the active components generally include transition metals [ 13 ], precious metals [ 14 ], rare earth elements [ 15 ], and some metal oxides [ 16 ]. 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 ].…”