TiO_2光催化降解甲醛的数值模拟

介绍了TiO2光催化降解甲醛的方法,建立了光催化降解甲醛的数学模型,并选择L-H动力学方程来描述光催化反应的降解过程.提出了一种新型反应器——插入光纤的直孔陶瓷反应器,并采用数值模拟的方法,用UDF编写反应过程,计算甲醛的降解过程,研究温度、净化风速和光照强度对甲醛降解速率的影响.发现光强越大,反应速率越大;净化风速太高或太低都会使反应速率减小;在一定的范围内,温度的升高会使光催化氧化反应速率增大,但是当温度进一步增加,光催化氧化反应速率就会呈下降的趋势.     

TiO2光催化降解甲醛气体的研究

以玻璃纤维为载体,用溶胶-凝胶法自制锐钛矿型TiO2光催化材料,分别对400℃、450℃、500℃不同温度下制备的纳米TiO2进行X衍射(XRD)、电镜扫描(SEM)分析,并用在不同温度下制备的TiO2光催化材料进行降解甲醛的实验,结果表明450℃下制备的TiO2光催化材料具有最佳的光催化活性。     

光催化对洁净厂房循环风单元中甲醛净化参数的优化研究

为了探讨洁净厂房循环风单元回风净化装置中光催化剂种类、用量、光照强度等参数对降解甲醛效率的影响,以确定光催化净化网参数配置的方案。采用酚试剂分光光度法测定甲醛浓度,在60 m~3的模拟洁净厂房内,通过正交试验筛选回风净化装置中光催化净化网对甲醛15 min降解效率的最优参数组合。试验结果表明,光催化剂用量对甲醛降解效率有显著性差异。直接分析发现净化参数对甲醛降解效率的影响大小顺序为光催化剂用量光照强度光催化剂种类。综合分析得出光催化净化网最佳参数配置为纳米TiO_2、光催化剂用量三遍(30 g/m~2)、紫外灯20 W。光催化净化网的最佳参数配置能够提高光催化净化网对洁净厂房中甲醛的降解效率。     

颜色对粉石英/纳米TiO_2涂料甲醛净化性能的影响

研究颜色对粉石英/纳米Ti O2涂料甲醛净化性能的影响。与未加颜色的对比样96%甲醛净化性能相比,有色涂料甲醛净化率都有所降低,红、橙、绿、兰、紫甲醛净化性能基本一致,为93.2%左右,降低了3%,黄色和黄绿色的甲醛净化性能降低较多,在90%左右,降低6%。黄绿色和黄色对近紫外光的吸收相对要强一些,对涂料甲醛净化率的影响要大一些;颜料点位占据涂膜表面,减少纳米Ti O2光催化的点位,会一定程度降低涂膜的光催化氧化效果。另一方面涂料的颜色越深,吸收可见光越多,涂膜温度也会略微升高,有助于提高光催化反应速度,共同作用的结果使有色涂料的甲醛净化性能有所降低。     

颜色对粉石英/纳米TiO2涂料甲醛净化性能的影响

研究颜色对粉石英/纳米TiO2涂料甲醛净化性能的影响.与未加颜色的对比样96％甲醛净化性能相比,有色涂料甲醛净化率都有所降低,红、橙、绿、兰、紫甲醛净化性能基本一致,为93.2％左右,降低了3％,黄色和黄绿色的甲醛净化性能降低较多,在90％左右,降低6％.黄绿色和黄色对近紫外光的吸收相对要强一些,对涂料甲醛净化率的影响要大一些;颜料点位占据涂膜表面,减少纳米TiO2光催化的点位,会一定程度降低涂膜的光催化氧化效果.另一方面涂料的颜色越深,吸收可见光越多,涂膜温度也会略微升高,有助于提高光催化反应速度,共同作用的结果使有色涂料的甲醛净化性能有所降低.     

净醛内墙乳胶漆的研制

介绍了除甲醛材料,着重论述了能与甲醛发生反应的祛醛乳液、光催化降解甲醛的纳米TiO_2、祛甲醛生物助剂的除醛效果,并通过优化配方,实现了净醛内墙乳胶漆高品质与环保完美结合。     

纳米光催化材料消除空气中低浓度甲醛的实验研究

通过与活性碳纤维吸附性能的对比,分析了纳米光催化材料消除甲醛的性能。实验研究了甲醛初始体积分数、TiO2质量分数和外界条件（温度、相对湿度和气流速度）对光催化性能的影响。实验结果表明,纳米光催化材料比单纯的活性碳纤维对甲醛的消除性能有一定程度的提高;单因素影响下温度对光催化性能影响较大;多因素交互作用下温度和甲醛的初始体积分数对光催化性能的影响较大。     

纳米TiO2-ACF光催化净化室内空气污染物试验

本文提出了纳米TiO2-ACF复合光催化净化室内空气技术,分析了不同条件下复合光催化净化网的净化效率,对ACF吸附网、纳米TiO2光催化净化网和纳米TiO2-ACF复合光催化净化网净化甲醛的净化性能进行了对比分析.复合光催化净化网在高风速且污染物质量浓度较低时净化效率高于其他两种净化网的净化效率近15%.该净化网对无机和有机污染物具有较强的吸附氧化能力、较小的空气阻力、无中间副产物生成,实现了ACF的原位再生,延长了净化网的使用周期.     

Cu-TiO2光催化降解甲醛气体的研究及应用

采用环境测试舱模拟可见光下的室内环境,以甲醛气体的光催化降解为探针反应,评价了通过纳米杂化和溶胶-凝胶技术制备的Cu-TiO2纳米晶体对甲醛气体的降解效果.用X射线衍射和紫外-可见分光光谱表征了掺杂纳米TiO2的晶体结构与光学性能.结果表明,Cu-TiO2在可见光源下具有比纯TiO2更好的光催化降解甲醛气体能力,并探讨了其在新型环保建材方面的应用.     

TiO_2/Fe-TiO_2复合材料的制备及其对甲醛降解性能的研究

采用水热合成法制备纯TiO_2和Fe-TiO_2光催化材料,然后将n型TiO_2半导体与p型Fe-TiO_2半导体复合,制备出具有p-n结的TiO_2/Fe-TiO_2复合光催化材料。实验表明,当铁掺杂量为0.5%(Fe/Ti摩尔比),制备的TiO_2/Fe-TiO_2光催化材料对甲醛降解性能最佳,其禁带宽度为3.02 eV,在甲醛浓度为0.08 mg/m3的环境条件下进行测试,紫外光照射3 h对甲醛气体的降解率达到30.3%。     

去除海水中TOC的新型药剂试验研究

为了验证LY-K01新型药剂在TOC去除率上的高效性,拟定了该药剂与传统药剂对海水TOC处理的对比实验,并对其实验方法与实验步骤进行了介绍,结合该药剂的药剂机理得出该处理药剂可真正做到将氧化、吸附、混凝结合为一体,效果良好,值得推广使用。     

O3/H2O2 treatment of methyl-tert-butyl ether (MTBE) in contaminated waters

The kinetics and efficiency of oxidation of methyl-tert-butyl ether (MTBE) in contaminated water employing O3/H2O2 advanced oxidation process is presented in this paper. Kinetic simulation is based on the model mechanism published in literature (Staehelin and Hoigne, Environ. Sci. Technol. 16 (1982) 676; Glaze and Kang, Ind. Eng. Chem. Res. 26 (1989) 1573) indicates that the oxidation of MTBE is primarily induced by the hydroxyl radical. The degradation of MTBE can be described by a pseudo-first-order kinetics in two phases. The first-phase covers MTBE concentrations greater than 10 mg L(-1) and the second-phase covers MTBE concentrations below 10 mg L(-1). The rate of oxidation of MTBE (at least in the first-phase) is limited by ozone mass transfer and increases with increasing ozone gas flow rate. The pseudo-first-order reaction rate constant varies from 2.0 x 10(-3) to 5.4 x 10(-3) s(-1) over the range of ozone gas flow rate employed in this investigation. An efficiency index is defined and its value for the oxidation of MTBE in different water is provided. The data provided show that remediation of MTBE-contaminated groundwater by O3/H2O2 process is more efficient and less costly than by the UV/H2O2 process.     

二氧化钛膜光催化氧化苯酚的影响因素研究(二)

研究了二氧化钛膜固定相光催化氧化苯酚水溶液的诸多影响因素（苯酚起始浓度、自来水中常见的无机阴离子和阳离子、自来水中苯酚的光催化氧化等）,为今后研究提高固定相光催化氧化效率的途径提供了依据。     

氧化沟系统除磷效果的提高途径

介绍了氧化沟技术的发展现状，通过分析生物除磷效果的影响制约因素以及氧化沟系统除磷效果差的症结，从加设厌氧池、减小硝态氮的影响等方面，提出了提高氧化沟系统除磷效果的有效途径。     

新型电气火灾消烟剂的研制

针对电气火灾中产生的大量有毒烟雾，研制一种细水雾型消烟剂，能够通过润湿、凝并、粘结等物理作用以及化学反应沉降烟尘，去除有毒气体，达到快速消烟目的，平均消烟效率达85％以上。该消烟剂为绿色无污染产品，不会造成消烟范围内设备、装置的短路和腐蚀，火灾现场容易清洁。     

O3／H2O2艺去除饮用水中2-MIB的效能与机制

以2-甲基异莰醇（MIB）为嗅味物质的代表物,采用过氧化氢／臭氧氧化（O3／H2O2）工艺去除水中嗅味物质,考察了O3／H2O2工艺对水中2一MIB的去除效能与主导作用机制。研究表明,投加H2O2显著提高了单独0,氧化对2-MIB的去除效能,H2O2与O3最佳物质的量比为0．3：1,且2-MIB去除效果随pH值的升高而升高。叔丁醇对2-MIB的去除表现出显著的抑制作用,在O3氧化2-MIB过程中,除O3分子氧化2-MIB外,O3在水中自分解产生的强氧化性的羟基自由基（HO·）也具有协同氧化作用。不同浓度的天然有机物（NOM）对2-MIB去除效果的影响不同,较低浓度的NOM促进了2-MIB的去除,但随着其浓度的升高,2-MIB去除率明显降低。O3／H2O2工艺对水中2-MIB表现出良好的去除效果,是强化去除水中2-MIB等致臭微量有机物的重要工艺。     

生物载体与曝气方式对氧化池氧转移特性的影响

对比研究了不同曝气量条件下,分别采用穿孔曝气和微孔曝气时,装填不同载体的接触氧化池的氧转移特性。结果表明,在试验范围内,各接触氧化池的氧总传质系数均随曝气量的增加而增大,但增加速度逐渐变缓。当曝气量为3.5 m3/h时,网格载体池的氧转移效率和动力效率达到最大值,分别为5.25%和3.22 kgO2/(kW.h),是竖管载体池和悬浮球载体池的1.14倍,是无载体池的1.22倍。当处理对象为生活污水时,接触氧化池内可采用微孔曝气+竖管(或悬浮球)载体;而当处理对象为高浓度有机废水时,可采用穿孔曝气+网格载体+悬浮球载体。     

Catalyzed UV oxidation of organic pollutants in biologically treated wastewater effluents

A batch reactor was used to evaluate the efficiency of advanced oxidation process of the organic pollutants in biologically treated wastewater effluents with UV/H2O2. A 450-W high-pressure mercury vapor lamp was used as the light source. During the degradation process, the concentration of the dissolved organic compounds could be increased by more than twofold due to the decomposition of microorganisms. This increase of the dissolved organic compounds was eliminated if the water was filtered before the photodegradation experiments. It is observed that the UV alone could play a role for the oxidation of the organic pollutants; however, the addition of a small amount of hydrogen peroxide promotes the degradation efficiency of organic compounds in wastewater. The best oxidation efficiency was obtained when the water samples were under acidic conditions (pH 5), and the rate of degradation was not enhanced with the increasing H2O2 dosages. The optimum H2O2 dose was between 0.01% and 0.1% for the oxidation processes in this study. The presence of the carbonate/bicarbonate ions in water inhibits the degradation of the organic compounds.     

UV-TiO2联用去除饮用水中阴离子表面活性剂的研究

采用UV-TiO2催化氧化联用工艺去除饮用水中低含量阴离子表面活性剂LAS.试验考察了玻璃纤维网膜数目、涂敷次数和LAS的初始浓度对LAS去除效果的影响,在LAS浓度为1 mg/L,紫外光强度为4 mw/cm2,3张玻璃纤维网膜分别涂敷3次条件下,反应100 min后,LAS的去除率超过90%.并建立了UV-TiO2催化氧化联用工艺降解LAS的动力学方程.     

Optimizing linear alkyl benzene sulfonate removal using Fenton oxidation process in Taguchi Method

Linear alkyl benzene sulfonate (LAS), which is the most common used anionic surfactant in detergents manufacturing, can discharge onto water resources through wastewater and causes change in taste and odor, disruption in water treatment processes, aquatics death, and oxygen transfer limitation. Accordingly, this article investigates to optimize LAS removal using Fenton oxidation process in Taguchi Method for the first time. LAS removal using Fenton oxidation was perused experimentally in a lab-scale reactor. In order to save relevant costs, 25 runs were qualified to specify the optimum conditions of Fenton oxidation using Taguchi method by Minitab 16 software. Sampling and testing procedures were executed based on the standard methods for the examination of water and wastewater. The optimum conditions included 900 mg/L hydrogen peroxide, 170 mg/L ferrous ion, pH of 4 and the reaction time of 20 min. Fenton oxidation, as a second order reaction with the rate coefficient of 0.0152 L/mg?min, provided 86.5% efficiency for LAS removal in the optimum conditions. Despite Fenton oxidation appeared as a high efficiency process in LAS removal, low removal efficiency of chemical oxygen demand corresponding with LAS affirmed its partial degradation.