TiO_2纳米带制备及光催化降解气相甲苯研究  

Photocatalytic Degradation of Toluene by TiO_2 Nanobelts:an Experimental Research

作　　者：吴淑娜[1] 蒋燕 陈清华[1] 辛言君[1] WU Shuna;JIANG Yan;CHEN Qinghua;XIN Yanjun(College of Resources and Environment,Qingdao Agricultural University,Qingdao 266109,China)

机构地区：[1]青岛农业大学资源与环境学院,山东青岛266109

出　　处：《环境科学与技术》2018年第9期12-16,21,共6页Environmental Science & Technology

基　　金：山东省自然科学基金青年基金项目(ZR2014EEQ007)

摘　　要：文章利用阳极氧化法制备Ti O2纳米带(Ti O2NBs),采用扫描电镜(SEM)、透射电镜(TEM)和能谱仪(EDX)对Ti O2NBs微观形貌和表面成分进行表征,并对其紫外可见漫反射光谱(UV-vis)和X射线衍射(XRD)进行了检测。以甲苯为目标污染物研究了Ti O2NBs对中低浓度(2.17~21.67 mg/L)甲苯气体的光催化降解,考察了甲苯初始浓度、催化剂用量、气体流速和光照条件4个因素对甲苯降解效果的影响,并考察了催化剂的稳定性。结果表明:甲苯降解率随着初始浓度的增大先增大后减小,当初始浓度为17.34mg/L时,降解时间为100 min时,降解率达到93.72%,为最佳降解效果;实验装置条件下,催化剂有效面积为32 cm2时为最佳;随着气体流速增大(0.5~3 L/min),甲苯降解效率呈现先上升后下降趋势,当流速为1.5 L/min时,甲苯的降解效率最高;紫外灯为光源时甲苯降解率显著高于可见光为光源时的降解率,前者比后者降解效率高50%。Laboratory experiment was carried out aiming at degradation of toluene by use of photocatalytic technology, for which TiO_2 nanobelts（TiO_2 NBs） were prepared by anodization. And then the micromorphology and elemental composition of TiO_2 NBs were characterized by SEM, TEM（transmission electron microscopy） and EDX（energy dispersive X-ray spectroscopy）, respectively; and the UV-vis absorption spectra（UV-vis） and X-ray diffractometer（XRD） were detected. Photocatalytic degradation of toluene in gas phase with concentration range 2.17-21.67 mg/L was conducted investigating effects of the factors including inlet concentration, catalyst dosage, gas velocity and light intensity, at the same time, stability of the TiO_2 NBs was studied. Results of the experiment showed that degradation rate of toluene increased firstly and then decreased with the increase of initial concentration; when the initial toluene concentration was 17.34 mg/L and illumination time 100 min the degradation rate attained the optimal value as 93.72%; and the optimal catalyst area was 32 cm-2 under the condition of the experiment system. Furthermore, with the increase of toluene gas flow-rate（up from 0.5 to 3 L/min）, toluene degradation rate rose at first but fell later; the optimal toluene degradation rate appeared when the flow rate was set at 1.5 L/min; and remarkably toluene degradation rate was 50% higher under ultraviolet light irradiation, higher than under visible light.

关 键 词：TiO2NBs 光催化降解 甲苯 

分 类 号：X701.7[环境科学与工程—环境工程]