Preparation And Photocatalytic Properties Of TiO₂Nanocomposite Supported On Activated Carbon

With the development of economy and consumption of energy, environmentalproblems are severity, especially our country that mainly consume coal. Energyconsumption brings a lot of environmental problems, such as the treatment of wastewater,air purification, which raise concern. In recent years, the technology of membraneseparation is widely applied in treatment of wastewater, but it has disadvantage of selectiveseparation alone and pollution of membrane. These shortcomings give rise to effect oftreatment of water and consumption of energy significant change over time and restrict thedevelopment of membrane separation technology. At the same time, nanometersemiconductor photocatalytic technology applys to the treatment of wastewater and thedegradation of organic pollutants and shows good effect. Especially semiconductorphotocatalytic technology of TiO2as basal material. This technology shows considerablepotential application value of settlement of air pollution and degradation of organicpollutants in wastewater thoroughly.By using carbon adsorption method coupls with normal method technology to prepareBi2O3, Bi2O3/TiO2and Y2O3/TiO2catalysts, butyl titanate, Bi2O3and Y2O3as raw materia-ls. After calcining the crystalline phase, particle size, dispersivity and optical absorptionproperties of obtained powder were characterized by means of thermogravimetric analysis-differential thermal analysis(TG-DTA), X-ray diffraction(XRD), transmission electronmicroscope(TEM), UV-Vis spectroscopy and BET. The results showed the addition ofcarbon black can prevent the reunion and sintering during the preparation, drying andcalcination process. The particles had uniform size, high dispersion behavior andagglomeration was little. The average grain size was13nm, surface area was88.32m2/g at600℃calcination for the Bi2O3. The average grain size was18.8nm, surface area was86.52m2/g at600℃calcination for the Bi2O3/TiO2. The average grain size was15nm,surface area was80.25m2/g at600℃calcination for the Y2O3/TiO2. Methylene blue solution as target degradation substance, nanometer Bi2O3,Bi2O3/TiO2and Y2O3/TiO2composite powder as catalysts to estimate photocatalyticperformance of the catalysts. The results showed Bi2O3, Bi2O3/TiO2and Y2O3/TiO2prepared by carbon adsorption coupling method had good photocatalytic effects formethylene blue. The orders of degradation rate on methylene blue in50min wasBi2O3/TiO2>Y2O3/TiO2> Bi2O3.