Ce_xMn_(1-x)O_2复合氧化物的制备及催化湿式氧化降解高浓度有机酸的应用

利用水热法制备CeO_2和一系列不同Ce/Mn原子比的Ce_xMn_(1-x)O_2复合氧化物的纳米球,对其进行XRD、XPS、SEM、H_2-TPR和N_2吸附-脱附的表征,并通过催化湿式氧化降解丁酸对催化活性进行测试,结果表明Ce_(0.2)Mn_(0.8)O_2对丁酸的降解呈现出优异的催化性能.该催化剂对高浓度的醋酸、丁酸以及两者混合酸的降解也具有高的催化活性,在185℃、0.9 MPa O_2条件下反应2 h,醋酸、丁酸以及两者混合酸COD(化学需氧量)的去除率分别高达89.8%、99.5%和99.4%.最后,对该催化剂催化湿式氧化降解丁酸、醋酸以及丁酸和醋酸的混合酸进行了动力学和稳定性方面的研究.

The Preparation of CexMn1-xO2 Mixed Oxides and the Applications for Catalytic Wet Air Oxidation of High Concentration Organic Acids

CeO2 nanospheres and CexMn1-xO2 nanospheres were prepared by PVP-assisted hydrothermal method and characterized by SEM,XPS,XRD,H2-TPR and N2 absorption-desorption.The catalytic wet air oxidation (CWAO) behavior of high concentration organic acids,including acetic acid,butyric acid and the mixture of ace tic acid and butyric acid,is tested over the Ce0.2Mn0.8O2 nanosphere,which turns out to be an efficient catalyst for the activation and degradation of high concentration organic acids.When the reaction operated at 0.9 MPa partial pressure of O2,185 ℃ for 2 h,the chemical oxygen demand (COD) removal can reach up to 89.8％,99.5％ and 99.4％ for acetic acid,butyric acid and the mixture of acetic acid and butyric acid,respectively.Noticeably,the kinetic studies of CWAO for three kinds of organic acids over the Ce0.2Mn0.sO2 reveal that the degradation of sole acid is easier than that of mixture acid.In addition,the Ce0.2 Mn0.8O2 oxides perform a good reusability during the cycle experiment even after six cycles.