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1.
采用搅拌式光催化反应器,以中压汞灯作光源,甲基橙为模型化合物,考察了Cu^2 对TiO2光催化活性的影响。研究发现,在此反应体系中甲基橙的降解为一级反应,甲基橙的光催化降解速率与光强度成正比,TiO2光催化剂的投加量为150mg/L、Cu^2 的加入量为200μg/L时光催化效果最佳。  相似文献   

2.
负载型TiO2固定相光催化降解含酚废水的试验研究   总被引:6,自引:0,他引:6  
以20W紫外灯为光源,研究了将TiO2粉末负载在硅胶颗粒上,对含酚废水进行光催化降解。由试验得出光催化反应过程中的工艺条件,在此基础上添加H2O2、Fe^3 、Cu^2 ,反应1h后,苯酚的降解率达95%以上。  相似文献   

3.
以太阳能固定膜光催化中试装置,研究了光解、初始浓度和平均光强等对双酚A(BPA)光催化去除的影响及BPA的矿化和在自来水中的处理效果.试验结果表明,BPA在日光照射下很难光解,其光催化降解呈表观一级反应,在平均光强介于5.7~23.5 W/m2时,表观反应速率常数和平均光强呈线性关系.太阳能光催化对BPA具有良好的矿化作用,但其降解与以UV254为光源的降解有不同的机理.太阳能光催化对自来水中BPA也具有较好的处理效果.  相似文献   

4.
磷钨酸季铵盐-β-环糊精包合物光催化降解甲基橙   总被引:2,自引:0,他引:2  
制备了磷钨酸季铵盐-β-环糊精包合物,并进行了初步表征,用正交实验优化了包合物的制备条件。在光催化反应仪中,以紫外灯为光源,以包合物为光催化剂,研究了其对模拟染料废水甲基橙溶液的光催化降解脱色的影响。讨论了影响光催化降解效果的溶液初始酸度、催化剂投加量和甲基橙的初始浓度等几个重要因素。  相似文献   

5.
以TiO2为催化剂、紫外灯为光源对乳酸进行光催化降解实验,考察了乳酸初始浓度、TiO2用量、反应时间、曝气方式等因素对乳酸降解率的影响,并在此基础上应用正交实验对降解条件进行优化,同时对乳酸的降解机理进行了探索研究。实验结果表明:以300 W紫外汞灯为光源,在乳酸初始浓度为0.5 g/L、TiO2量为0.20 g/L、反应时间120 min、持续通入空气鼓泡的条件下,乳酸降解效果最佳,乳酸降解率为99.9%;降解12 h总有机碳去除率达91.2%。乳酸光催化降解的反应途径为:乳酸脱羧生成乙醇,乙醇被氧化生成乙醛,进而氧化为乙酸,所有的中间产物被继续降解,最终矿化为CO2和H2O等小分子物质。  相似文献   

6.
自制TiO2光催化涂料,重点对所制备的涂料在室内进行降解甲醛研究,考察了在不同分散剂、不同光催化剂以及不同甲醛初始浓度、不同光源、不同温度和不同湿度等环境因素下涂料对甲醛降解率的影响。结果表明,选用聚丙烯酸钠离子型分散剂,铜金属掺杂TiO2光催化剂制备的光催化涂料对甲醛降解率达80%以上且具有良好的耐久性,在室温(20℃左右)湿度50%日光灯照射下,甲醛初始浓度5μL时效果最佳。  相似文献   

7.
自行设计了气固相光催化实验系统。以铝材为担载体,TCM和TCE为模拟污染物,在常温,常压下,对辐射光源,气体相对湿度,污染物反应浓度等因素对TCM和TCE的光催化降解反应的影响进行了研究。结果表明,在研究所采用的实验条件下,辐射光源采用254nm时的降解效率要比采用365nm时高10%左右。气体相对湿度为40%时光催化降解效率最高;随着污染物反应浓度的增加,TCM的降解效率降低,而TCE的降解效率增加,初步的反应动力学研究结果表明,TCM和TCE在二氧化钛表面的光催化降解反应可采用Langmuir-Hinshelwood动力学方程来表征。  相似文献   

8.
以玻璃纤维为载体,将TiO2负载到其表面形成了空间玻璃纤维反应器,引入Fe3+作为掺杂改性离子,形成了负载TiO2/Fe3+的空间玻璃纤维光催化反应器,并以高压汞灯为光源进行了光催化降解水中苯酚的实验研究,考察了影响苯酚光催化降解的因素,确定了在UV365~250 W光源照射下,pH为3~5,O2通入量1.0 L/(min.L),反应器内上升流速为0.7 m/min等实验条件下,初始浓度为30 mg/L的苯酚废水经120 min光催化反应后,降解率可达到85%,矿化率可达80%。  相似文献   

9.
以玻璃纤维为载体,将TiO2负载到其表面形成了空间玻璃纤维反应器,引入Fe3+作为掺杂改性离子,形成了负载TiO2/Fe^3+的空间玻璃纤维光催化反应器,并以高压汞灯为光源进行了光催化降解水中苯酚的实验研究,考察了影响苯酚光催化降解的因素,确定了在UV365-250 W光源照射下,pH为3-5,O2通入量1.0 L/(min.L),反应器内上升流速为0.7 m/min等实验条件下,初始浓度为30 mg/L的苯酚废水经120 min光催化反应后,降解率可达到85%,矿化率可达80%。  相似文献   

10.
负载型TiO2固定相光催化降解含酚废水的试验研究   总被引:1,自引:0,他引:1  
以20W紫外灯为光源,研究了将TiO2粉末负载在硅胶颗粒上,对含酚废水进行光催化降解.由试验得出光催化反应过程中的工艺条件,在此基础上添加H2O2、Fe3+、Cu2+,反应1 h后,苯酚的降解率达95%以上.  相似文献   

11.
铂铈共掺杂纳米TiO2的制备、表征及光催化性能   总被引:1,自引:1,他引:0  
杜鹏  赵振波  陈刚 《环境工程学报》2013,7(10):3933-3938
以钛酸四丁酯为前驱体,过氧化氢为氧化剂,采用简单易行的低温氧化法制备出晶粒尺寸较小(平均尺寸25 nm)的二氧化钛纳米粒子。通过贵金属Pt掺杂TiO2(Pt-TiO2)、稀土元素Ce掺杂TiO2(Ce-TiO2)和Pt、Ce共掺杂TiO2(Pt/Ce-TiO2)的掺杂的方法对二氧化钛进行改性。通过XRD,XPS,TEM,紫外漫反射等表征手段对制备的样品进行表征。通过可见光下降解罗丹明B来测试其光催化活性。实验结果表明,由Ce掺杂的TiO2光催化剂对有机污染物的最大降解能力略大于Pt掺杂的TiO2,2种元素进行共同掺杂时对应的TiO2光催化剂降解能力最大。  相似文献   

12.
活性炭纤维负载TiO2光催化降解甲醛的影响因素   总被引:1,自引:0,他引:1  
利用自制光催化气体反应器体系,以活性炭纤维负载TiO2作催化剂,在紫外光照射下模拟降解室内污染气体甲醛,测试了活性炭纤维负载TiO2催化剂的催化活性,探讨了紫外光光强、催化剂的酸度、反应器内湿度及反应时间等控制反应的主要因素对甲醛降解率的影响。结果表明,活性炭纤维与TiO2的协同作用大大提高了对甲醛的降解效果;紫外光强增倍对甲醛降解率有一定提高,但提高幅度仅为11.71%;活性炭纤维用pH=5的TiO2溶胶浸泡做催化剂对甲醛的降解效果最好,60 min内降解率达到68.37%;反应器内的湿度为81%甲醛降解率最高,反应60 min后达82.2%;随着反应时间的延长,甲醛降解率的上升幅度不断减小,最高只能达到94.59%。  相似文献   

13.
为了消除甲醛气体对人类的危害,对甲醛气体的光催化降解行为进行了研究。采用沉淀-胶溶法制得了具可见光活性的纳米TiO2溶胶,然后将其负载于经过预处理的泡沫镍板上,置于自置的光催化反应器中,考察了在可见光照射下对密闭空间里面一定浓度的甲醛气体的降解情况。采用乙酰丙酮分光光度法,在最佳的检测条件下检测气相中甲醛气体经不同光照时间后的浓度。研究发现,负载了氮掺杂改性的TiO2的泡沫镍板在可见光照射下能够有效降解气相中的甲醛,反应240 min后对甲醛气体的降解率为93%;而同样条件下反应器中只有处理过的泡沫镍板时,甲醛气体浓度基本保持不变。  相似文献   

14.

The present work mainly deals with photocatalytic degradation of a herbicide, erioglaucine, in water in the presence of TiO2 nanoparticles (Degussa P-25) under ultraviolet (UV) light illumination (30 W). The degradation rate of erioglaucine was not so high when the photolysis was carried out in the absence of TiO2 and it was negligible in the absence of UV light. We have studied the influence of the basic photocatalytic parameters such as pH of the solution, amount of TiO2, irradiation time and initial concentration of erioglaucine on the photodegradation efficiency of erioglaucine. A kinetic model is applied for the photocatalytic oxidation by the UV/TiO2 system. Experimental results indicated that the photocatalytic degradation process could be explained in terms of the Langmuir–Hinshelwood kinetic model. The values of the adsorption equilibrium constant, K, and the second order kinetic rate constant, k, were 0.116 ppm? 1 and 0.984 ppm min? 1, respectively. In this work, we also compared the reactivity between the commercial TiO2 Degussa P-25 and a rutile TiO2. The photocatalytic activities of both photocatalysts were tested using the herbicide solution. We have noticed that photodegradation efficiency was different between both of them. The higher photoactivity of Degussa P-25 compared to that of rutile TiO2 for the photodegradation of erioglaucine may be due to higher hydroxyl content, higher surface area, nano-size and crystallinity of the Degussa P-25. Our results also showed that the UV/TiO2 process with Degussa P-25 as photocatalyst was appropriate as the effective treatment method for removal of erioglaucine from a real wastewater. The electrical energy consumption per order of magnitude for photocatalytic degradation of erioglaucine was lower with Degussa P-25 than in the presence of rutile TiO2.  相似文献   

15.
以陶瓷为载体,采用溶胶-凝胶法制备了银离子和铈离子共掺杂TiO2的负载型光催化剂——T-AC/陶瓷,研究了pH值、双氧水用量、催化剂用量、紫外灯强度、废水的初始浓度等因素对T-AC/陶瓷光催化剂降解甲基橙染料废水的影响。结果表明,当pH为2、双氧水用量为0.5 mL/100 mL、催化剂用量为3 g/L、紫外灯功率为20 W、废水初始浓度为10mg/L时,甲基橙的降解率可达85.9%,并且甲基橙的光催化降解属于一级动力学方程,T-AC/陶瓷催化剂有较高的活性和稳定性,在废水处理中具有较好的应用前景。  相似文献   

16.
Noble metal Ag-decorated, monodisperse TiO2 aggregates were successfully synthesized by an ionic strength-assisted, simple sol–gel method and were used for the photocatalytic degradation of the antibiotic oxytetracycline (OTC) under both UV and visible light (UV–visible light) irradiation. The synthesized samples were characterized by X-ray diffraction analysis (XRD); UV–vis diffuse reflectance spectroscopy; environmental scanning electron microscopy (ESEM); transmission electron microscopy (TEM); high-resolution TEM (HR-TEM); micro-Raman, energy-dispersive X-ray spectroscopy (EDS); and inductively coupled plasma optical emission spectrometry (ICP-OES). The results showed that the uniformity of TiO2 aggregates was finely tuned by the sol–gel method, and Ag was well decorated on the monodisperse TiO2 aggregates. The absorption of the samples in the visible light region increased with increasing Ag loading that was proportional to the amount of Ag precursor added in the solution over the tested concentration range. The Brunauer, Emmett, and Teller (The BET) surface area slightly decreased with increasing Ag loading on the TiO2 aggregates. Ag-decorated TiO2 samples demonstrated enhanced photocatalytic activity for the degradation of OTC under UV–visible light illumination compared to that of pure TiO2. The sample containing 1.9 wt% Ag showed the highest photocatalytic activity for the degradation of OTC under both UV–visible light and visible light illumination. During the experiments, the detected Ag leaching for the best TiO2-Ag photocatalyst was much lower than the National Secondary Drinking Water Regulation for Ag limit (0.1 mg L?1) issued by the US Environmental Protection Agency.  相似文献   

17.
氮掺杂二氧化钛可见光催化降解曙红Y溶液   总被引:2,自引:1,他引:1  
采用溶胶凝胶法制备了氮掺杂二氧化钛光催化剂,用XRD、SEM、FTIR和粒度分析仪对催化剂进行了表征,并且在可见光作用下对曙红Y溶液进行了光催化降解实验。研究了催化剂的投加量、曙红Y的初始浓度、光照时间和pH对曙红Y溶液的光降解效果。结果表明,以可见光作光源,催化剂的投入量为0.4 g,曙红Y溶液的初始浓度为20 mg/L,光照时间为50 min,pH=4条件下,曙红Y溶液的降解率达98.87%。  相似文献   

18.
Coupled Bi2O3/TiO2 photocatalysts were fabricated by sol–gel and hydrothermal methods and characterized using various spectroscopy techniques. Photocatalytic reduction of Cr(VI) in aqueous solution, together with the synergistic effect of photodegradation of bisphenol A (BPA), was investigated using these coupled Bi2O3/TiO2 under visible-light irradiation. Coupling of Bi2O3 inhibited the phase transformation from anatase to rutile and extended absorption region to visible light. Bi ions did not enter TiO2 lattice and were more likely to bond with oxygen atoms to form Bi2O3 on the surface of TiO2. Photovoltage signals in visible range revealed the effective interfacial charge transfer between Bi2O3 and TiO2. Two percent Bi2O3/TiO2 exhibited the highest photocatalytic activity of visible-light-induced reduction of Cr(VI). The addition of BPA effectively increased the photocatalytic reduction of Cr(VI). Simultaneously, the presence of Cr(VI) promoted the degradation of BPA, which was demonstrated by the investigation of TOC removal yield and generated intermediates. A possible mechanism of photocatalytic reduction of Cr(VI) and degradation of BPA in Bi2O3/TiO2 system was proposed. The synergistic effect, observed between reduction of Cr(VI) and degradation of BPA, provides beneficial method for environmental remediation and purification of the complex wastewater.  相似文献   

19.
综合光催化氧化苯的动力学过程、光辐射场模型和质量守恒定律,采用平板型反应器建立了碳纳米管/二氧化钛/壳聚糖(CNTs/TiO2/CS)催化薄膜光催化氧化气相苯的数学模型;该模型考虑了光强、相对湿度、初始浓度与气体流速对气相苯光降解的影响。结果表明,建立的数学模型与实验结果吻合较好。  相似文献   

20.
利用自制光催化气体反应器体系,以活性炭纤维负载TiO2作催化剂,在紫外光照射下模拟降解室内污染气体甲醛,测试了活性炭纤维负载TiO2催化剂的催化活性,探讨了紫外光光强、催化剂的酸度、反应器内湿度及反应时间等控制反应的主要因素对甲醛降解率的影响。结果表明,活性炭纤维与TiO2的协同作用大大提高了对甲醛的降解效果;紫外光强增倍对甲醛降解率有一定提高,但提高幅度仅为11.71%;活性炭纤维用pH=5的TiO2溶胶浸泡做催化剂对甲醛的降解效果最好,60 min内降解率达到68.37%;反应器内的湿度为81%甲醛降解率最高,反应60 min后达82.2%;随着反应时间的延长,甲醛降解率的上升幅度不断减小,最高只能达到94.59%。  相似文献   

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