Influence and Characterization of Acidity on Fine Silicon Powder Immobilized Photocatalyst

TiO2 photocatalyst was supported with tetrabutyl titanate sol as precursor and fine silicon powder obtained from ferroalloys factory as carrier to discuss the influence of pH value of gel precursor on microstructure and activity of photocatalyst in the process of synthesizing nano-TiO2 by using sol-gel method, the purpose of which is to provide fundamental data for the recycle of photocatalytic material.Under the irradiation of ultraviolet light, the photocatalytic degradation rate of methyl orange solution was used to characterize the photocatalytic activity of the sample.The specific surface area of the sample was tested by N2 desorption method, crystal form of TiO2 was analyzed by X-ray powder diffraction, and the microtopography of the sample wasobserved by scanning electron microscopy.The experimental results showed that the acidity of gel precursor could greatly affect the specific surface area and photocatalytic activity of the pho-tocatalyst, and the optimum pH value of the precursor was determined as 2.0, and at this time the specific surface area of photocatalyst could reach 34.0 m2/g.In the sample, the proporticn of anatase to futile is 7:3, which makes 10 mg·L-1 methyl orange solution fade after irradiation by 15Wultraviolet light for 24 h, and the degradation rate might be up to 98.1%.