摘要
以弱酸性红RN染料为目标降解物,分析纳米TiO2对其光催化降解的机理.采用XRD表征自制纳米TiO2光催化剂的晶相结构.通过单因素实验,研究光催化剂投加量、染液初始pH值等因素变化对纳米TiO2光催化降解弱酸性红RN染液的影响.结果表明,纳米TiO2受光照激发在其表面生成了具有高活性和强氧化能力的羟基自由基(·OH),将弱酸性红RN染料催化降解为N2、H2O、CO2、Na2SO4等无害物质.采用溶胶凝胶法制备的纳米TiO2晶粒均为锐钛矿相,粒径大小为19.2nm.在300W金卤灯照射下,光催化反应240min时,0.25g纳米TiO2对100mL质量浓度为5mg/L、pH=5的弱酸性红RN染料溶液的降解率达94.2%.
The main degradation mechanism of weak acid red RN dye target degradation pollutant by the photocatalytic degradation of nano-TiO2 photocatalyst was studied .The crystal phase structure of self-made nano-TiO2 was characterized by X-ray diffraction （XRD） .The effects of different dosing quantity of photocatalyst and initial pH value on photocatalytic degradation were investigated by single factor method .The results show that high active and strong oxidizing hydroxyl radical （ ？ OH） is generated on the surface of nano-TiO2 by light irradiation .The weak acid red RN dye is finally degraded to N 2 ,H2 O , CO2 and Na2 SO4 .Nano-TiO2 fabricated by a sol-gel method has single anatase ,the crystallite size of which is 19.2nm .When the dosing quantity of photocatalyst is 0.25g /100mL ,and the initial concentra-tion and pH value of the solution are 5mg/L and 5 ,respectively ,the degradation rate of weak acid red RN dye solution is 94.2% under 300W metal halide lamp irradiation for 240 min .
出处
《西安工程大学学报》
CAS
2014年第1期35-39,共5页
Journal of Xi’an Polytechnic University
基金
陕西高校省级重点实验室科研项目(2010JS007)
陕西省科学技术研究发展计划项目(2013K09-04)
关键词
纳米TIO2
光催化
降解机理
弱酸性红RN染料溶液
nano-titanium dioxide
photocatalysis
degradation mechanism
weak acid red RN dye solu-tion
