SHENFang?fang,LIUYong?ze,MAJun,et al.Development and Application of Evaluation Method for Hydroxyl Radical Formation during Heterogeneous Catalytic Ozonation[J].China Water & Wastewater,2023,39(13):25-31.
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Development and Application of Evaluation Method for Hydroxyl Radical Formation during Heterogeneous Catalytic Ozonation

China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU] volume: 第39卷 Number: 第13期 Page: 25-31 Column: Date of publication: 2023-07-01
Author(s):
SHEN　Fang?fang1; 2;  LIU　Yong?ze1; 2;  MA　Jun3;  JIANG　Jin4;  ZOU　Jin?ru1; 2;  GENG　Nan?nan1; 2;  FENG　Li1; 2;  ZHANG　Li?qiu1; 2
（1. Beijing Key Laboratory for Source Control Technology of Water Pollution， Beijing Forestry University， Beijing 100083， China； 2. Engineering Research Center for Water Pollution Source Control & Eco?remediation， College of Environmental Science and Engineering， Beijing Forestry University， Beijing 100083， China； 3. School of Environment， Harbin Institute of Technology， Harbin 150090， China； 4. Institute of Environmental and Ecological Engineering， Guangdong University of Technology， Guangzhou 510006， China）
Keywords:
heterogeneous catalysts;  catalytic ozonation;  chain reactions;  hydroxyl radical yield;  hydroxyl radical formation rate
Abstract:
Heterogeneous catalytic ozonation technology is widely used in the advanced treatment of wastewater. Heterogeneous catalysts can induce ozone (O3) decomposition into hydroxyl radical (·OH), thus enhancing the oxidation of ozone-resistant organic matters. Nowadays, there are many kinds of catalysts and their catalytic performance are uneven in practical applications. Thus, it is urgent to establish an evaluation method to comparatively evaluate their catalytic performance, so as to provide a basis for the selection and optimization of catalysts in engineering application. In this study, based on the chain reaction of ·OH formation during catalytic ozonation, an evaluation method (taking both ·OH formation rate and ·OH yield into account) was developed and verified. Subsequently, catalytic performance of two classes of six catalysts were evaluated, including carbon materials such as carbon nanotubes (CNTs) and N-doped carbon nanotubes (N-CNTs), and metal oxides, such as Fe-Mn-, FeOx-Al2O3, NiOx-Al2O3 and CuMn2O4. The results showed that, at about 3.8 mg/L O3 dose, N-CNTs (0.01-0.06 g/L) induced fast ·OH formation [i.e., 2.52-8.61 μmol/(L·min)] while the ·OH yield was low (i.e., 50.20%-59.66%). Fe-Mn-Al2O3, FeOx-Al2O3 and NiOx-Al2O3 (0.05-0.4 g/L) had higher ·OH yield (i.e., 72.51%-89.50%), but with relatively slow ·OH formation rate [i.e., 0.66-3.68 μmol/(L·min)]. CuMn2O4 had the best performance with highest ·OH yield (i.e., 76.61%-89.46%), and fast ·OH formation rate [i.e., 1.10-5.87 μmol/(L·min)] and ·OH production rate increased rapidly along with the catalyst dosage [i.e., 0.014 6 μmol/(min·mg)]. The developed method and the results in this study are helpful for heterogeneous catalysts selection and can provide technical guidance for the practical application of catalytic ozonation process.
Last Update: 2023-07-01