The Study On Preparation, Characterization And Photodegradation Of Phenol Waste Water Of ABO₃ Perovskite Type Rare Earth Mixed Oxides

In most coal related chemical industries, vast amount phenol waste water will beproduced. High consistency phenol waste water can be recycled, but as to the lowconsistency phenol waste water, an ideal way to process it hasn't yet been found. Inthis paper, the perovskite type rare earth mixed oxides LaBO₃ photocatalyst and Bsite doped LaB_1-xB′_xO₃ photocatalysts were prepared by citrate-nitrate combustionmethod, and physical chemistry character and optical property and conductivity ofcatalysts were verified by powder X- ray diffraction, surface area, temperatureprogrammed reduction, FT infrared spectra, fluorescence spectrum, ultraviolet visiblediffuse reflectance spectroscopy, transmission electricity mirror and electricconductance testing technology. The photocatalytic activity of these catalysts hasbeen tested by photodegradation of phenol in aqueous solution. The emphasis is onthe effects of B site doping content on the photocatalytic property, and on therelationships between the structure and photocatalytic activity as well. Photocatalytic degradation mechanism and reaction kinetics of phenol degradation were discussedsimply.The current research indicate that catalyst LaAlO₃ shows high surface area,negative apparent activation energy, and better photo- catalyst under ultra violet ray,but narrower echo range to light, lower percentage of visible light use. After doping Bset with iron, the samples echo range to light increased. LaAl_0.6Fe_0.4O₃ shows the bestoptical function and photo-catalyst activity, not only under ultra violet ray but alsovisible light, and it will be ascendant photocatalyist for application. Direct lightdegradation, photo-catalyst and photo-oxidation co-exist and compete with each otherin the phenol photo-catalyst degradation process. After liner-fitting, reaction kineticsequation conforms to fist grade reaction kinetics law.