UV/Fenton/杂多酸体系对染料曙红Y的光解作用研究

为改善Fenton反应的氧化效率,选择杂多酸为活化剂,建立了一种新的光催化体系。在光化学反应器中,以紫外灯为光源,以磷钨酸为光催化助剂,研究了UV/Fenton/杂多酸体系对曙红Y模拟染料废水的光催化降解的影响,并就杂多酸辅助光催化降解染料的机理,影响染料光催化降解速率的因素,提高染料光催化降解效率的途径进行了初步探讨。结果表明,溶液中H2O2投加量、Fe2+浓度、溶液pH值是影响催化光解效果的重要因素。实验得出反应的适宜条件是:pH为5～6,30%H2O2的投加量为2 mL,FeSO4的剂量约为0.02 g/L。     

印染废水的光催化氧化研究

以活性炭负载TiO2薄膜为催化剂,采用光催化氧化法分别处理靛蓝类染料、三苯甲烷类染料和偶氮类染料模拟废水以及某印染厂的出水。研究了光化时间、废水pH值及COD对处理效果的影响。结果表明：光催化氧化处理印染废水的最适光化时间为240min,最适pH值为4,且在这几种染料中,靛蓝类染料最易降解,而偶氮类染料最难降解。     

二氧化钛平推流光催化反应器降解染料过程中氮素的变化

研究了在平推流光化学反应器中采用纳米TiO2光催化降解水中染料化合物。结果表明:染料化合物能被光催化有效地降解为NH+4-N、NO-3-N和其他无机离子,不同结构类型染料的降解速率不同,但均符合准一级动力学模型;通过监测降解过程中无机氮产物的含量,发现染料类化合物在光催化过程中有机氮先降解成NH+4-N,再被继续氧化成NO-3-N,由于强氧化环境的作用,NH+4-N向NO-3-N转化过程中,不经过中间价态的NO-2-N。     

水中活性艳红K-2BP光催化分解机理初探

本文用金属卤素灯作光源,用TiO2作催化剂,研究水中活性艳红染料K-2BP的光催化分解机理。发现,光催化分解属动力学一级反应;强碱、强酸条件下有利于催化分解;提高水中溶解氧量可使光解速率增大;光解过程有消耗OH-或生成H+;盐酸、醋酸中的Cl-、Ac-参与了光催化反应竞争,使染料的光解速率下降;光解过程中,染料中的发色基团-N=N-被氧化断裂,芳环较难被破坏。      

偶氮染料4BS光催化降解的特性研究

在二相流化床光催化反应器中 ,研究了染料 4BS光催化降解的特性 ,试验结果表明 :难生物降解染料 4BS光催化降解后 ,可提高其可生化性 ,且BOD5/CODCr值显著提高。     

悬浮TiO_2-铂电极体系光电催化降解染料

文章采用悬浮TiO2-铂电极体系,以悬浮TiO2作为光催化剂,在两片铂电极间施加一定的电压,研究了染料Procion Red MX-5B在NaCl和Na2SO4电解质溶液中的光电催化降解。光电催化的效率与NaCl溶液的浓度和外加电压密切相关,在0.3mol/L的NaCl溶液中,外加电压8V的条件下,10min内染料的脱色率达到95%,而同时间内光催化脱色率只能达到35%。当外加电压超过5V时,电降解几乎与光电催化具有相同的染料脱色率,然而电降解并不能使染料降解的中间物矿化。光电催化能够在反应的最初一个小时去除溶液中80%的TOC,相同时间内光催化能够去除50%。光电催化与光催化都不能完全矿化所处理的染料,原因在于溶液中生成了非常稳定的降解产物。在Na2SO4溶液中,外加电压只能轻微的提高染料的脱色率,但却不能促进中间产物的分解。     

钙钛矿CaFeO_3光催化降解大红染料废水性能的研究

用柠檬酸络合法制备钙钛矿型复合氧化物CaFeO3,并以其为光催化剂对水溶性染料进行光催化降解实验。讨论了光催化反应时间、催化剂投加量、光照强度、pH值、以及外加氧化剂(H2O2)等因素对光催化活性的影响。实验结果表明:在催化剂投加量0.4g,降解时间180min,pH值2,光照强度200W,H2O2的投加量5mL时,大红染料的降解率可达99.83%。     

二氧化钛催化剂的制备及其催化性能研究

TiO₂光催化剂具有光催化活性高,吸收紫外光性能强,无毒等特点。本文主要采用溶胶-凝胶法合成TiO₂溶胶,分析反应条件对二氧化钛溶胶形成的影响,研究合成所得TiO₂的光催化性能。为了改进二氧化钛的光催化性能,将二氧化钛分散于壳聚糖体系中,以提高二氧化钛的光催化效果,通过对甲基橙这种较难降解的染料化合物的催化降解实验,探究二氧化钛在降解印染废水方面的光催化性能。     

纳米ZnO光催化剂的制备及性能研究

以Zn(CH3COO)2·H2O和NH4HCO3为原料,以室温固相反应和微波辐射技术相耦合的方法制备出粒径在19nm左右的ZnO光催化剂,同时以活性艳兰KN-R为模拟染料废水考察了所制备纳米ZnO的光催化性能。结果表明,所制备纳米ZnO具有良好的光催化活性,在适宜的操作条件下,活性艳兰KN-R的脱色率在96%以上,COD的去除率在69%以上。此外,在染料的浓度为30～100mg/L时,ZnO/UV体系光催化降解活性艳兰KN-R符合一级反应动力学模型。     

轻工业三废处理与综合利用

X791.3 9703049太阳能光催化降解法去除水中罗丹明染料的研究/陈非力(中科院广州能源研究所卜·//化工环保/化工部北京化工研究院环保所一1997,17(l)一3~6环信X一32 在太阳光的紫外线辐射下,应用载有TIOZ薄层的平板式光催化反应器,进行了光催化降解法去除水中罗丹明染料的试验。结果表明,当紫外线辐射强度平均为33w/mZ、反应时间为18min时,水中罗丹明染料浓度由lomg/lJ降至。.olmg/IJ,达到国家排放标准。探讨了太阳能光催化反应系统的改进方向及工业化应用的有关问题。图2参5X791.3 9703050气浮一厌氧一好氧工艺处理高浓度印染废水/戚…     

Detection of intermediates in the TiO2-assisted photodegradation of Rhodamine B under visible light irradiation

The photocatalytic degradation of dye Rhodamine B （RhB） in the presence of TiO2 nanostdpe or P25 under visible light irradiation was investigated. The degradation intermediates were identified using Infrared spectra （IR spectra）, ^1H nuclear magnetic resonance （^1HNMR） spectra, and gas chromatography-mass spectroscopy （GC-MS）. The IR and the ^1HNMR results showed that the large conjugated chromophore structure of RhB was efficiently destroyed under visible light irradiation in both the photocatalytic systems （TiO2 nanostfipe or P25 and Rhodamine B systems）. GC-MS results showed that the main identified intermediates were ethanediotic acid, 1,2-benzenedicarboxylic acid, 4-hydroxy benzoic acid and benzoic acid, which were almost the same in the TiO2 nanostdpes and P25 systems. This work provides a good insight into the reaction pathway（s） for the TiO2-assisted photocatalytic degradation of dye pollutants under visible light irradiation.     

混晶纳米TiO_2的制备及其光催化降解有毒有机污染物

以无定形TiO2沉淀为前驱体,在水热条件下得到了含板钛矿(121)相混晶纳米TiO2,考察了水热反应的温度和时间等因素对含板钛矿型TiO2光催化活性的影响.采用XRD、TEM对制备的TiO2进行初步表征,并结合光催化(λ≤387 nm)降解有机染料的光活性探针反应.结果表明,水热温度为150℃,时间为24 h时,可制得具有较高光催化活性的纳米TiO2,其纳米尺寸为14.20 nm,板钛矿相含量63.6%,锐钛矿含量为36.4%.光催化实验中跟踪研究了其对染料酸性桃红(sulforhodmineB,SRB)的褪色及2,4-DCP的降解情况,并对降解中间产物H2 O2、.OH进行跟踪测定,实验结果表明板钛矿相混晶TiO2的光催化主要涉及.OH氧化历程,光照射9 h对SRB和2,4-DCP的矿化氧化分别达到89%和78%,循环5次光催化降解SRB实验,催化剂表现出较好的稳定性,催化性能无明显变化.     

流化床光催化反应器处理偶氮染料4BS废水中试研究

采用 3 0～ 40目负载型光催化剂 ,以高压汞灯为紫外光源 ,研究了偶氮染料 4BS废水在流化床光催化中试反应器中的降解 ,针对有关工艺参数和反应动力学进行了考察。结果表明 :所用中试反应器对 4BS具有较好的降解效果 ;催化剂浓度存在最佳值 ;适当增加光强及溶解氧浓度均有利于光催化降解效率的提高 ;染料 4BS溶液的光催化降解过程符合表现一级反应动力学规律 ,并且表观反应速率常数与 4BS初始浓度之间具有近似负一级的动力学关系     

Photocatalytic degradation of the dye sulforhodamine-B： A comparative study of different light sources

The photocatalytic degradation of dye pollutant sulforhodamine-B （SRB） in aqueous titanium dioxide （TiO2） dispersions was examined under three lighting regimes： UV light （330 nm〈λ〈 380 nm）, sunlight, and visible light （λ〉450 nm）, all investigated at pH=2.5. Total organic carbon （TOC） and chemical oxygen demand （CODer） assays show that the degradation rate of SRB is much higher when irradiated with UV and sunlight compared with visible light. The temporal concentration changes of SRB illustrated a first-order reaction and the rate constant, k, is 0.197 min^-1, 0.152 min^-1, 0.027 min^-1, respectively, under the three lighting conditions. The final mineralized products were amine compounds identified by infrared spectrophotometry. When irradiated with visible light, the photocatalytic degradation rate could be improved by lowering the H2O2 concentration and inhibited by increasing the H2O2 concentration, but results contrary to the above were obtained when UV light was used for irradiation.     

TiO2/beads as a photocatalyst for the degradation of X3B azo dye

The feasibility of photocatalytic degradation of X3B azo dye by TiO2/beads photocatalyst was studied.The effects of parameters such as the amount of TiO2/beads,airflow ,as well as the concentrations of H2O2,Fe^3 ,Mg^2 and Na^ on the photocatalytic degradation of X3B azo dye were also studied.The results showed that 25mg/dm^3 X3B azo dye can be photocatalytically degraded completely by 30 min illumination with a 375W medium pressure mercury lamp.Adding a small amount of H2O2 or Fe^3 ,the efficiencies of photocatalytic degradation of X3B azo dye were increased rapidly.The mechanisms of the reaction and the role of the additives were also investigated.After 120 hours TiO2/beads showed no significant loss of the photocatalytic activity.     

TiO_2/beads as a photocatalyst for the degradation of X_(3B) azo dye

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Recent advances based on the synergetic effect of adsorption for removal of dyes from waste water using photocatalytic process

The problem of textile dye pollution has been addressed by various methods,mainly physical,chemical,biological,and acoustical.These methods mainly separate and/or remove the dye present in water.Recently,advanced oxidation processes(AOP)have been focused for removal of dye from waste water due to their advantages such as ecofriendly,economic and capable to degrade many dyes or organic pollutant present in water.Photocatalysis is one of the advance oxidation processes,mainly carried out under irradiation of light and suitable photocatalytic materials.The photocatalytic activity of the photocatalytic materials mainly depends on the band gap,surface area,and generation of electron–hole pair for degradation dyes present in water.It has been observed that the surface area plays a major role in photocatalytic degradation of dyes,by providing higher surface area,which leads to the higher adsorption of dye molecule on the surface of photocatalyst and enhances the photocatalytic activity.This present review discusses the synergic effect of adsorption of dyes on the photocatalytic efficiency of various nanostructured high surface area photocatalysts.In addition,it also provides the properties of the water polluting dyes,their mechanism and various photocatalytic materials;and their morphology used for the dye degradation under irradiation of light along with the future prospects of highly adsorptive photocatalytic material and their application in photocatalytic removal of dye from waste water.     

Photocatalytic degradation of Acid Blue 62 over CuO-SnO2 nanocomposite photocatalyst under simulated sunlight

The novel CuO-SnO2 nanocomposite oxide photocatalysts were prepared by simple co-precipitation method, and characterized by X- ray diffraction, transmission electron microscopy, N2 adsorption-desorption measurement and UV-Vis diffuse reflectance spectroscopy. The photocatalytic activities of CuO-SnO2, evaluated using the photodegradation of Acid Blue 62 as a probe reaction under the irradiation of Xenon light, were also found to be related to the calcination temperature and the molar ratio of Cu to Sn. The maximum photocatalytic activity of the CuO-SnO2 photocatalyst was observed to be calcined at 500~C for 3 h （the molar ratio of Cu to Sn was 1：1） due to the sample with good crystallization and high surface area. It also showed much higher photocatalytic activity in treatment dye wastewater under simulated sunlight irradiation compared to Degussa P25 TiO2.     

CNT/CdS/壳聚糖-H2O2可见光光催化甲基橙脱色研究

利用共沉淀法制备了具有可见光响应的CNT/CdS复合薄膜光催化材料.以氙灯模拟日光光源,并以双氧水辅助氧化,对甲基橙进行光催化降解,探讨了不同工艺、催化剂用量、双氧水用量、甲基橙初始浓度、溶液pH值、无机阴离子对光催化降解脱色的影响以及催化剂的重复使用性.实验结果表明:双氧水对CNT/CdS光催化甲基橙脱色产生协同作用...     

Rubber sheet strewn with TiO2 particles:Photocatalytic activity and recyclability

A new method for the preparation of rubber sheet strewn with titanium dioxide particles (TiO₂-strewn sheet) is presented. This simple and low cost method is based on the use of TiO₂ powder (Degussa P25) being strewn onto the sheet made from rubber latex (60% HA) through a steel sieve. The characteristic of the TiO₂-strewn sheet was studied by using scanning electron microscopy/energy dispersive X-ray spectrometer (SEM/EDS) and X-ray diffractometer (XRD) techniques. The photocatalytic activity of TiO₂-strewn rubber sheet was evaluated using Indigo Carmine (IC) dye as a model for organic dye pollutant in water. The results showed that the TiO₂-strewn sheet could degrade IC dye solution under UV light irradiation. The effects of pH, initial concentration, and the intensity of UV light on the photodegradation were also investigated. Kinetics of the photocatalytic degradation was of the first-order reaction. The used TiO₂-strewn sheet can be recovered and reused. The recycling uses did not require any cleaning between successive uses and no decline in the photodegradation efficiency was observed compared with freshly prepared TiO₂-strewn sheet.