典型非均相臭氧催化剂特性研究及催化氧化效能评估

Study on characteristics of typical heterogeneous ozone catalysts and evaluation of catalytic oxidation efficiency

采用SEM、XRF、XRD、BET和FT-IR等表征方法对四种常用臭氧催化剂的表面形貌、化学组分、晶体结构、孔隙结构、含氧基团等基本特性进行研究。臭氧催化剂多以球形分子筛(SiO_(2)/Al_(2)O_(3))为载体,负载的催化剂以多金属氧化物(如Fe、Mn、Cu、Ni、Ce和Ti的氧化物)为主,比表面积介于100~300 m^(2)/g,孔隙以5~12 nm的介孔为主,孔容积0.2~0.5 cm^(3)/g。针对化工园区废水、煤化工废水、染料废水的臭氧催化氧化试验研究表明,表面积大、负载Ni、Mn氧化物和拥有较高表面羟基基团的催化剂具有更高的催化效能,可有效提高臭氧氧化对COD、UV_(254)的去除效率。非均相催化剂性能评估系统和方法可用于实际工程的臭氧催化氧化工艺设计及催化剂选型。

The surface morphology,chemical composition,crystal structure,pore structure and oxygen-containing group of four commonly used ozone catalysts were respectively studied by the characterization methods of SEM,XRF,XRD,BET and FT-IR.The catalysts were supported by molecular size of SiO_(2)and Al_(2)O_(3).The catalytic compositions were mainly polymetallic oxides(such as Fe,Mn,Cu,Ni,Ce and Ti oxides),with specific surface area of 100~300 m^(2)/g,mesoporous pores of 5~12 nm and pore volume of 0.2~0.5 cm^(3)/g.The experimental study on ozone catalytic oxidation of wastewater from chemical industrial park,coal chemical industry and dye wastewater shows that the catalysts with larger surface area,higher contents of Ni and Mn oxides and higher surface of hydroxyl groups behave higher catalytic efficiency,and achieve effective removal of COD and UV_(254).The evaluation system and method of heterogeneous catalyst performance established in this paper can be used for the process design and catalyst selection of catalytic ozonation in practical engineering.