TiO2-SiO2-Fe2O3的表征及其光催化降解染料废水

第5卷�第1期环境工程学报Vol.5,No.12011年1月ChineseJournalofEnvironmentalEngineeringJan.2011TiO2/SiO2/��Fe2O3的表征及其光催化降解染料废水储金宇1�姜�玲1�李�宁1�刘松峰2(1.江苏大学环境学院城市水资源与水环境国家重点实验室江苏大学研究中心,镇江212013;2.中石油大港油田供水公司,天津300280)摘�要�以��Fe2O3为磁性核心,通过溶胶�凝胶法制备出三层结构的复合光催化剂TiO2/SiO2/��Fe2O3。通过X射线衍射、扫描电镜、透射电镜、振动样品磁强计和紫外�可见分光光谱分析进行表征。SiO2包覆膜可以减弱内层��Fe2O3对光催化效果的不利影响,有效地阻隔高温时��Fe2O3磁核与TiO2之间的熔结。以亚甲基蓝为目标反应物评价其光催化活性。结果表明:在紫外光照射4h内对亚甲基蓝(10mg/L)的降解率达到98�8%。TiO2/SiO2/��Fe2O3的吸收光强不但在紫外光区有所增加,而且在可见光区的响应范围也大幅增加,提高了光能利用率。催化剂具有的磁性使其易于被分离回收,在紫外光照射4h时TiO2/SiO2/��Fe2O33次使用后对亚甲基蓝的降解率仍可达95%。关键词�光催化�染料废水�磁性�降解�亚甲基蓝中图分类号�O643��文献标识码�A��文章编号�1673�9108(2011)01�0043�05CharacterizationofTiO2/SiO2/��Fe2O3andphotocatalyticdegradationofdyewastewaterChuJinyu1�JiangLing1�LiNing1�LiuSongfeng2(1.ResearchCenterofStateKeyLabofUrbanWaterResourceandEnvironment,SchoolofEnvironment,JiangsuUniversity,Zhenjiang212013,China;2.PetroChinaDaGangOil�fieldWaterSupplyCompany,Tianjin300280,China)Abstract�ThecompositephotocatalystTiO2/SiO2/��Fe2O3withathree�tierstructurewassynthesizedviasol�geltechnology,��Fe2O3asthemagneticcore.Themagneticcorewas��Fe2O3.Thecatalystwascharacter�izedbyX�raydiffraction,scanningelectronmicroscope,trasmissionelectronmicroscope,vibratingsamplemag�netometerandultraviolet�visiblespectroscope(UV�vis).SiO2resultedinreducingtheadverseeffectsbetweentheinnerlayerandtheexternalTiO2.ItalsoplayedanimportantpartinpreventingsinterofTiO2and��Fe2O3athightemperature.Thephotocatalyticactivitieswereevaluatedtakingmethyleneblue(MB)astargetreactan.tTheexperimentalresultsshowthat98�8%ofMB(10mg/L)wasphotodegradatedunderUVlightirradiationfor4h.TheintensityoflightabsorptionofTiO2/SiO2/��Fe2O3increasednotonlyintheUVregion,butalsoinvisi�blelightrange.Thisdirectlyleadstheimprovementoflightutilization.Themagneticphotocatalystparticleswereeasilyseparatedandrecoveredusingmagneticseparation.Thedegradationrateofmethyleneblueremainedat95%afterusingthreetimes.Keywords�photocatalysis;dyewastewater;magnetic;degradation;methyleneblue基金项目:江苏省创新基金资助项目(12230000