纳米TiO_2光催化降解水溶性染料溶液的研究

研究了纳米ＴｉＯ２光催化剂对活性黄Ｘ６Ｇ、活性红Ｘ３Ｂ、活性蓝ＸＢＲ、碱性绿、碱性紫５ＢＮ、碱性品红等６种染料溶液的光解脱色效果。结果表明，在ｐＨ２的酸性溶液中，对浓度为６０ｍｇ／Ｌ的６种染料溶液的脱色率均超过９３．３％；即使对浓度达２００ｍｇ／Ｌ的活性蓝溶液，其脱色率仍可达７８．８％。染料溶液的ｐＨ值对纳米ＴｉＯ２光催化脱色效果影响较大     

载钛活性炭纤维的制备及其对水中罗丹明B的光催化降解

通过溶胶凝胶法制备载钛活性炭纤维(TiO2-ACF)复合材料,采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、紫外-可见吸收(UV-Vis)、傅里叶红外分光光度计(FT-IR)、X射线光电子能谱(XPS)对TiO2-ACF进行了表征,并研究了TiO2-ACF对水中罗丹明B的光催化性能.结果表明,煅烧温度为400—600℃时,负载在ACF上的TiO2为锐钛矿型,当煅烧温度上升到700℃时,TiO2开始出现金红石型,600℃时煅烧制备的TiO2-ACF对水中罗丹明B的降解效果最佳;TiO2-ACF对罗丹明B的吸附能力比ACF低;但是在紫外光条件下,60 min后TiO2-ACF对罗丹明B的降解率比ACF、TiO2对罗丹明B的降解率分别高8.6%和16.2%,TiO2-ACF表现出较高的光催化活性.     

TiO_2纳米管修饰电极处理反渗透浓水研究

研制了新型的TiO2纳米管修饰电极,应用于反渗透膜浓水的电化学氧化处理;利用扫描电镜和线性极化曲线对电极进行了表征;考察了电解时间、电流密度和pH值因素对电化学氧化处理反渗透膜浓水的影响;并分析了电极对反渗透浓水中各有机物组分的去除效果。实验结果表明TiO2纳米管修饰电极对反渗透浓水具有较高的电催化性能。     

贵金属负载TiO_2光催化降解甲苯研究

采用Degussa P25 TiO2粉末,利用光沉积法制备贵金属负载光催化剂M/TiO2(M分别为Pt、Pd、Ag和Au)。通过气相甲苯光催化降解实验考察M/TiO2的光催化活性。实验结果表明:负载1.0 wt%的Pt、Pd、Ag和Au四种贵金属均可提高TiO2光催化降解甲苯的效率,其中Pt/TiO2的光催化活性最佳。循环伏安法(CV)、塔菲尔(Tafel)和Mott-Schottky电化学测试证明Pt的负载抑制光生电子和空穴的复合,提高载流子浓度,进而增强TiO2光催化活性。     

Preparation and characteristics of high performance paper containing titanium dioxide photocatalyst supported on inorganic fiber matrix

A novel paper-based material containing titanium dioxide (TiO₂) photocatalyst was successfully prepared by a papermaking technique with the internal addition of inorganic fibers on which TiO₂ particles were supported. Photodegradation performance of acetaldehyde gas, an indoor pollutant, and the durability of the TiO₂-containing papers were investigated under UV irradiation. Ceramic fiber suspension and polydiallyldimethylammonium chloride as a cationic flocculant were mixed, followed by the addition of TiO₂ suspension and anionic polyacrylamide. Subsequently, the inorganic mixture was poured into a pulp suspension, and TiO₂ handsheets then prepared by a papermaking method. The tensile strength of TiO₂-containing paper without a ceramic carrier decreased by more than 30% after 240-h UV irradiation (2 mW/cm²), although the strength of the TiO₂ sheet with ceramic fibers remained reasonably stable. The efficiency of acetaldehyde decomposition by the TiO₂ paper containing an inorganic carrier was nearly equal to that of the carrier-free TiO₂ paper. Scanning electron microscopic observation suggested that most TiO₂ particles were predominantly supported on the inorganic fiber matrix, and were mostly out of contact with organic pulp fibers. The TiO₂ paper with an inorganic carrier demonstrated both excellent photocatalytic performance and durability, which before had been mutually incompatible for organic materials containing TiO₂ photocatalyst. The two-stage mixing procedure for TiO₂ sheet-making is promising for the simple manufacture of high performance paper with photocatalytic ability.     

TiO2光催化性能及其降解污染物影响因素的研究进展

在简要介绍了TiO2光催化降解机理的基础上，综述了影响纳米TiO2光催化性能的因素及提高其光催化能力的途径。     

阳离子艳红染料的光催化降解

本文研究了以沉淀法制备的TiO2为催化剂，紫外杀菌灯为光源，对阳离子艳红染料进行光催化降解的可行性，结果表明，在实验条件下，本系统对阳离子艳红染料有明显的降解效果，浓度为10mg/L的阳离子艳红染料经过30min的处理，其降解率＞88％，此外，还探讨了溶液初始pH值，催化剂的投加量，光照距离和液层高度等因素对光降解反应的影响。     

水泥固定TiO2光催化降解苯酚水溶液的研究

以高压汞灯为光源。研究水泥固定TiO2在光反应器内光催化降解苯酚水溶液。通过正交试验，探讨了TiO2含量、初始溶液pH值，流速以及Fe3 浓度对光催化的影响。试验结果表明，在该固定床光催化反应器内，载体型TiO2对苯酚水溶液有明显的光解作用，最高光降率可以达到80％以上。在此基础上，提出了较为合理的处理工艺参数。另外，负载型光催化剂光照使用70h后，未见有TiO2脱落，且光催化活性无明显变化。这为制备负载型TiO2光催化剂提供了新的途径。     

超声-紫外光协同催化体系降解水中菲

以纳米TiO_2为催化剂,采用超声-紫外光协同催化体系降解水中菲,并考察了菲降解率的影响因素。实验结果表明:不同类型TiO_2对菲降解率的大小顺序为锐钛矿型TiO_2P25型TiO_2金红石型TiO_2;超声-紫外光协同催化体系对菲的降解率大于单独超声体系或紫外光催化体系,且均遵从一级反应动力学规律;在超声频率为60k Hz、声强为0.233 W/cm2、TiO_2投加量为0.06 g/L、pH为4.0、H_2O_2浓度为19.59 mmol/L的条件下降解75 min后,超声-紫外光协同催化体系对初始质量浓度为0.96 mg/L的菲的降解率可达76.78%。     

掺铁TiO2对庚烷气相光催化活性的研究

以乙酰丙酮铁和钛酸四丁酯为前驱体,制备掺铁TiO2复合光催化剂,以光催化降解正庚烷为反应模型,测定掺铁对TiO2光催化剂的结构、光吸收和光催化活性的影响．XRD的表征结果显示,焙烧温度升高,锐钛矿型TiO2转化成金红石型,且在700℃下有铁板钛矿生成;UV-Vis的结果表明,TiO2掺铁后增强了在可见光区的吸收,并且随着含铁量的增大,红移增大,提高了对可见光的利用率．相同掺铁量(Fe／Ti=0．07)下,500℃焙烧的光催化剂对庚烷的光催化降解活性最高,300℃次之,700℃最差．相同焙烧温度下,掺铁量在0．007-0．07范围内,光催化活性随掺杂量的增大而下降．