多元改性二氧化钛的制备及其性能研究

Study on preparation of multi-element modified titanium dioxide and performances thereof

采用浸渍法制备了铁-钐-镱-二氧化钛改性光催化剂,以苯酚为目标降解物,讨论了影响光催化剂性能的因素和提高光催化剂性能的方法。通过FE-SEM、XRD、UV-Vis等表征手段初步探讨了共掺杂提高二氧化钛光催化活性的机理。实验结果表明:常温、常压下,质量浓度为20 mg/L的苯酚废水(pH=7),当催化剂加入量为2.5 g/L、焙烧温度为550℃、金属(铁、钐、镱)掺杂量各为0.5%(质量分数)时,经4 h紫外光照其对苯酚的去除率可达90%以上。改性后的二氧化钛光催化剂在可见光下也能够显示出很好的活性。

Fe-Sm-Yb-TiO2 photocatalysts were synthesized by immersion method.With phenol as degradation target, the in- fluencing factors of catalyst performance and the methods of improving the performance of catalyst were discussed.A prelimi- nary discussion about the mechanism of co-doping improving photocatalytic activity of TiO2 was also made by means of FE- SEM, XRD, and UV-Vis etc..Experiments showed that the most suitable conditions were as follow ： when the mass concentra- tion of phenol wastewater was 20 mg/L （normal temperature and pressure ）, the pH was 7, the dosage of catalyst was 2.5 g/L, the calcining temperature was 550℃, and the doping rate of Fe, Sm, and Yb were all 0.5% （mass fraction ）, the degradation rate was up to 90% under the UV light for 4 h.The modified titanium dioxide catalyst also demonstrated fine activity under the visible light.