Preparation And Photocatalytic Properties Of LaAlO₃ And Its Doped Modified Materials

In order to alleviate the shortage of water resources and the serious water pollution in industrialized cities,the research on water treatment and reusing technology has been developing continuously.As a new green water treatment technology,photocatalytic oxidation technology has been widely concerned.In this paper,self-made fulvic acid solution was used as a simulated wastewater.LaAlO₃ and B-doped modified photocatalysts were prepared by sol-gel method.The highest catalytic activity was prepared under the best conditions and optimal photocatalytic reaction conditions.XRD,laser particle size analyzer and other means to characterize the lattice and morphology of the self-made catalyst,and further catalyze the degradation of dye wastewater,investigate the treatment capacity of various wastewater,and provide a theoretical reference for solving the water pollution problem.The main results are as follows:?1?LaAlO₃ catalyst prepared by sol-gel method?volume ratio of metal salt ion to citric acid is 1:2.5,and the calcination temperature is 800??had the highest activity for degrading the FA solution.,the average particle diameter in aqueous solution was188.3?m,the particle purity was high and the surface was dense and porous.?2?When the photocatalytic reaction was carried out with dark reaction for 30 min,the UV lamp turning on for 210 min,using 10 mg/L FA solution as simulated wastewater.,The photocatalytic degradation efficiency under different conditions showed that When the condition is that the dosage of LaAlO₃ is 0.3 g/L,the amount of aeration is 0.8 L/min,and the intensity of ultraviolet light is 30 W,the reaction activity of was the highest and the reaction rate was the fastest.The UV₂₅₄54 removal rate was98.7%,the TOC degradation rate was 38.9%.At the end of the reaction,the fulvic acid fluorescence peak had substantially disappeared,and no other fluorescent substance was produced.?3?When LaAl_0.9Fe_0.1O₃ was doped with iron ions by B-position aluminum ions(volume ratio of Al?NO₃?₃ to Fe?NO₃?₃ is 0.9:0.1,the XRD pattern diffraction peak intensity of LaAl_0.9Fe_0.1O₃ was the largest,the average particle size was reduced to118.5?m,and the porosity was increased.The UV₂₅₄54 and TOC removal rates of the FA solution are 98.8%and 60.3%,respectively.The reactivity and the reaction rate were higher than that of LaAlO₃.At 180 min,the UV₂₅₄54 degradation rate of FA has stabilized,and there is no characteristic fluorescence peak in the water sample taken at 180 min,and no other fluorescent substance was produced.?4?The UV₂₅₄54 and TOC removal rates of used LaAlO₃ to FA solution gradually decreased to 85.9%,29.8%,while the removal rates of used LaAl_0.9Fe_0.1O₃ degraded FA solution were 92.3%and 53.4%.The stability of LaAl_0.9Fe_0.1O₃ after modification was enhanced,and the UV₂₅₄54 and TOC degradation effects during cyclic use were maintained at 90%?50.0%above.The regeneration performance is significantly improved.?5?LaAlO₃ and LaAl_0.9Fe_0.1O₃ can effectively decolorize the dye wastewater under the optimal reaction conditions.The modified catalyst LaAl_0.9Fe_0.1O₃ still showed higher reactivity and reaction rate.The decolorization rate of LaAl_0.9Fe_0.1O₃?98.4%and86.0%?was higher than the decolorization rate of LaAlO₃?95.0%and 71.5%?.