Preparation of Mn-Ce oxide-loaded Al_(2)O_(3) by citric acid-assisted impregnation for enhanced catalytic ozonation degradation of dye wastewater  

作　　者：Shaopeng Li Weichao Li Yun Wu Xianming Zheng Xuehui Zhao Ning Nan Hongwei Zhang 

机构地区：[1]School of Environmental Science and Engineering,TianGong University,Tianjin 300387,China [2]State Key Laboratory of Separation Membranes and Membrane Processes,TianGong University,Tianjin 300387,China [3]School of Material Science and Engineering,TianGong University,Tianjin 300387,China

出　　处：《Chinese Journal of Chemical Engineering》2024年第12期237-250,共14页中国化学工程学报（英文版）

基　　金：supported by the National Key Research and Development Program(2023YFC3207003);the National Natural Science Foundation of China(51878448).

摘　　要：The performance of supported catalysts is significantly affected by the dispersion degree of the active components on the support.In this study,citric acid(CA)was used as a modifier to prepare Al_(2)O_(3)supported Mn-Ce oxides(Mn-Ce/CA-Al_(2)O_(3))by the impregnation-calcination method.The characterization results showed that adding citric acid enhanced the dispersion of Mn-Ce oxides on the support,rendering Mn-Ce/CA-Al_(2)O_(3)with a larger specific surface area and abundant surface hydroxyl groups,thereby providing more reaction sites for catalytic ozonation.The Mn-Ce/CA-Al_(2)O_(3)exhibited excellent catalytic ozonation performance in degrading Reactive Black 5(RB5)dye.It achieved nearly complete decolorization of RB5 within 60 min,with a COD removal efficiency of 60%,which was superior to the sole ozonation(30%).Furthermore,the Mn-Ce/CA-Al_(2)O_(3)system demonstrated significant degradation of RB5 over a wide pH range of 3e11.Based on the XPS and EPR analysis results,a preliminary mechanism of catalytic ozonation over the Mn-Ce/CA-Al_(2)O_(3)was proposed.The redox cycle of Mn^(3+)/Mn^(4+)and Ce^(3+)/Ce^(4+)effectively accelerated the electron transfer process,thus promoting the generation of reactive oxygen species(ROS)and improving the degradation of RB5.Meanwhile,the Mn-Ce/CA-Al_(2)O_(3)exhibited superior catalytic stability and effective treatment capabilities for real dye wastewater.

关 键 词：Catalytic ozonation Alumina-based catalyst Mn-Ce oxides Reactive Black 5 Reaction mechanism 

分 类 号：X703[环境科学与工程—环境工程] O643.36[理学—物理化学]