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1.
针对室内装修带来的室内甲醛污染的问题,阐述了TiO2纳米材料光催化降解甲醛的现状,并对TiO2纳米材料光催化降解甲醛中存在的问题进行了讨论,提出了制备SnO2纳米颗粒修饰的TiO2纳米管(SnO2/TiO2纳米管)的必要性.  相似文献   

2.
探讨了可见光照射下,甲醛气体的光催化降解行为.结果表明,催化剂用量增加,甲醛气相光催化降解速率增加,当催化剂达到一定量后,甲醛气相光催化降解速率不再增加;甲醛气体初始浓度增加,光催化反应速率亦增加,但过高的初始浓度会使光催化反应速率或甲醛降解率降低;甲醛气相光催化反应过程中氧气O2和水H2O对于反应的进行都是必不可少的,但过多的水分却对光催化反应有抑制作用;甲醛气相光催化反应符合Langmuir-Hinshelwood(L-H)动力学模型.  相似文献   

3.
制备了纳米复合催化剂TiSiW12O40/TiO2,利用IR、XRD和TEM对其进行了表征.研究了钨硅酸的负载量、溶液pH值、溶液浓度、光照时间等对TiSiW12O40/TiO2光催化降解亚甲基蓝的影响.TiSiW12O40/TiO2光催化降解亚甲基蓝的反应符合一级反应动力学.  相似文献   

4.
选取镍镉网为基体,利用硫酸氧钛和醋酸锰合成了一种锰钛光催化剂,XRD分析其主要由锐钛矿型的TiO2晶体及α-MnO2构成,根据Scherrer方程计算晶粒尺寸约为20nm和30nm。以甲醛为污染物,研究了污染物初始浓度、催化剂用量、反应相对湿度和光能量等反应条件对甲醛降解效率的影响,通过实验得出了最佳的反应条件。  相似文献   

5.
以紫外灯为光源、纳米TiO2为催化剂,探讨了光催化反应降解咖啡因废水的影响因素,获得光催化降解咖啡因的最佳条件:咖啡因初始质量浓度为10 mg/L,纳米TiO2用量为1 g/L,pH为10.89,H2O2质量浓度为1.0 g/L.  相似文献   

6.
以纳米TiO2为催化剂,紫外灯为光源,对X-3B溶液的光催化降解动力学进行了研究。降解反应动力学拟合结果表明,降解动力学规律符合Langmuir-Hinshelwood一级反应动力学模型。  相似文献   

7.
用传统的溶胶-凝胶法、改进的溶胶-水热法制备了纳米TiO2和掺杂纳米TiO2,通过对甲基橙有机废水的光催化降解模拟实验,比较不同产品的光催化性能,发现改进的溶胶-水热法优于传统的溶胶-凝胶法,掺杂纳米TiO2优于纯纳米TiO2.  相似文献   

8.
概述了TiO_2光催化降解制药废水的机理,对制药废水光催化降解速率的影响因素、提高降解效率的途径以及纳米TiO_2光催化技术的研究应用进行了综述.并提出TiO_2光催化技术处理制药废水的需要重点解决的研究工作.  相似文献   

9.
以四氯化钛为前驱体,用溶胶一凝胶法制备了TiO2纳米膜,并进行了炼焦厂废水的光催化降解实验,考察了制备条件对其光催化降解性能的影响。结果表明最佳工艺条件为:四氯化钛:乙醇:水=30:400:25,溶胶体系pH=7,掺铁量Fe:Ti=0.16,干凝胶在450℃煅烧2h,由此制成的TiO2纳米膜光催化降解炼焦厂废水的降解率超过79%。  相似文献   

10.
本文设计一个半开放式综合性实验项目,运用自制的小体积密闭试验舱来检测纳米TiO_2材料对甲醛光催化降解性能。实验设计中,对舱体进行综合评价后,选取水热法制备的铁掺杂纳米TiO_2和氮掺杂纳米TiO_2作催化剂降解甲醛,比较了其在可见光下对甲醛的降解效果,最后通过动力学研究可知甲醛在纳米TiO_2表面氧化反应符合一级动力学方程。该综合性实验项目设计覆盖了多学科交叉的综合训练,有助于把学生培养成"具有创新精神和实践能力的高级专门人才"。  相似文献   

11.
The crystal form of TiO_2 is a crucial focus of research on the photocatalytic degradation of gaseous pollutants by TiO_2-based composite photocatalysts. To explore the synergistic effect of mixed crystalline TiO_2 on gaseous organic-pollutant photocatalytic degradation, we synthesized a series of TiO_2 nanoparticles with controllable phase ratios. We explored the role of the TiO_2 phase ratio on the photocatalytic activity and degradation pathway in the photodegradation of 2-propanol(IPA). We estimated the crystallite size and crystal proportions of anatase and rutile by X-ray diffraction. We used the Brunauer-Emmett-Teller method to calculate the specific surface area and Fourier transform infrared spectroscopy to characterize the surface chemistry of the samples. Our results show the photocatalytic activities of pure anatase and the sample with 8.6% rutile to be much better than those of the samples with a phase junction and pure rutile. As such, anatase is the better option for the study of photodegradation design and preparation of gas-phase organic pollutants.  相似文献   

12.
以Ti(OC4H9)4为原料,采用溶胶-凝胶法制备出光催化剂纳米TiO2和TiO2-Fe2O3复合粉体,并用制得的样品在紫外光催化条件下对刚果红、碱性品红、酸性蓝等三种水溶性染料溶液进行降解实验,讨论了两种催化剂对染料的光催化降解脱色效果。结果表明TiO2-Fe2O3复合粉体对酸性蓝和刚果红的降解效果好于纳米TiO2,两者对碱性品红的降解效果相当。  相似文献   

13.
An efficient visible-light-responsive BiOBr/TiO_2 heterojunction nanocomposite was fabricated successfully using in-situ depositing technique at room temperature by introducing Bi OBr onto the surface of TiO_2 nanobelts pre-prepared by hydrothermal reaction and etched with H_2SO_4. The obtained particles were characterized by XRD, SEM, TEM, XPS, UV-Vis DRS and PL techniques. BiOBr/TiO_2 heterojunction nanocomposites with different mass ratios of m(Bi OBr)/m(TiO_2) were discussed in order to get the best photocatalytic activity, and BiOBr/TiO_2-1.0 was proved to be the optimal mass ratio. BiOBr/TiO_2-1.0 exhibited excellent photocatalytic activity in the degradation of Rh B compared with TiO_2 nanobelts, pure Bi OBr and the mechanical mixture of TiO_2 nanobelts and Bi OBr. At last, a possible mechanism of photocatalytic enhancement was proposed.  相似文献   

14.
以钛酸丁酯为前躯体,采用溶胶-凝胶法制备TiO2粉体,并通过TEM和XRD分析方法对其结构性能进行表征.检测结果表明:TiO2粉体由5-10nm的球形颗粒组成,晶型为锐钛矿型.通过在不同光源下催化降解水杨酸溶液,对其光催化活性及影响因素进行了分析.实验结果表明:紫外光下此TiO2纳米粉体的光催化活性较高.  相似文献   

15.
纳米Ti0_2光催化氧化法处理碱性紫5BN染料废水的研究   总被引:2,自引:0,他引:2  
以脱色率为主要考察指标,研究了纳米TiO2光催化氧化法处理三苯甲烷染料碱性紫5BN的最佳工艺条件。试验结果表明,采用紫外光源为20 W的KL-1型光催化反应器,在平均粒径为30 nm的TiO2悬浮体系中,TiO2能够高效脱除碱性紫5BN的色度。纳米TiO2光催化降解碱性紫5BN、活性艳红K-2BP,在KL-1型紫外光实验装置上的最佳工艺条件为:碱性紫5BN在初始浓度80 mg/L时,TiO2用量1.0 g/L,pH值为3,外加催化剂H2O2加入量为2.5 ml/L,反应2.5 h,碱性紫5BN最大脱色率为98%。本试验为进一步进行碱性紫5BN的工业化处理提供了科学依据,并为纳米TiO2光催化氧化法处理其他染料废水提供借鉴。  相似文献   

16.
This paper studies the adsorption of diethyl phthalate (DEP,an environmental hormone) on the surface of nanoscale TiO_2, effects of pH value of solutions, initial concentrations of DEP and additive surfactant on photocatalytic degradation and dynamics of DEP. Under ultra violet illumination, the interaction between DEP and surfactants including DBS (sodium dodecylbenzenesulfon-ate), CTAB (cetyltrimethylammonium bromide), and OP-10 (nonylphenol polyoxyethylene ether) was exploited from the perspective of degradation speed calculated by the data of high pressure liquid chromatography (HPLC) and UV-Vis spectra, respectively. Photocatalytic degradation of DEP followed pseudo first-order reaction kinetics. DEP as substrate degraded fast when its initial concentration was 130 mg/L. TiO_2 had certain adsorption ability of DEP. TiO_2 could adsorb the most DEP at the approximately neutral pH of 6.91. Degradation of DEP was not affected obviously by additives OP-10 and DBS. Degradation rate of DEP was not enhanced greatly in the presence of surfactants, but degradation of DBS was sped up. Degradation rate of DEP was depressed in the presence of additive CTAB. The more CTAB was added, the less DEP was degraded. Degradation rate of CTAB became slow with the increase of initial CTAB concentration. The possible adsorption models among TiO_2, DEP and surfactants were given.  相似文献   

17.
以Ti(SO4)2为原料,采用氨水水解法制备氮掺杂二氧化钛前驱体,煅烧得到氮掺杂二氧化钛纳米粉体,作为功能活性组分.利用FT-IR红外光谱和激光粒度等方法对所制备的活性组分进行表征.将功能活性组分分散到水性乳胶涂料体系中,通过高速搅拌使其均匀分散,制得改性乳胶涂料.以30w日光灯管为光源,用甲醛降解反应考察了复合乳胶涂料的光催化活性.结果表明,复合了该活性组分的乳胶涂料具有优良的光催化净化空气的性能.N掺杂量对其光催化活性有较大的影响,当氮的掺杂量为0.7wt%,七天后光催化甲醛降解率达到最高92%.  相似文献   

18.
通过调整反应的pH以及给予不同的后处理方式,以水热法合成了不同形貌的氯氧化铋,采用XRD、SEM、紫外可见分光光度计等手段对其组成、形貌和光催化性能进行了表征,考察不同合成条件下的氯氧化铋对罗丹明B和甲醛的降解性能。拓展了氯氧化铋在液相污染体系和气相污染体系中对有机污染物降解的应用。实验表明:BiOCl(9U)和BiOCl(6)均获得了最好的光催化效果,其对罗丹明B的降解率在10 min和20 min时均达到了99%,而氯氧化铋则在120 min时对高质量浓度甲醛的降解率达到67%。  相似文献   

19.
ZiO2 was prepared by the hydrolyzation method in (NH4)2SO4-modified TiCl4 solution, and TiO2 photocatalysts were obtained by accelerating the precipitation of TiO2 powder in a high-temperature water bath. The photocatalysts were characterized by Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), Raman spectrum and UV-Vis (Ultraviolet-Visible) spectrometry techniques, and the photocatalytic activity in phenol-contaminated water was investigated. The results showed that photocatalysts calcined at 400 ℃ had a specific surface area of 138.2 m^2/g and an average particle size of 9 nm, and a significant increase in thermal stability of anatase phase. At the calcination temperature of 700 ~C, the crystal form of TiO2 started to change into rutile (anatase: 97%, rutile: 3%). The activity of TiO2 photocatalysts prepared with (NH4)2SO4-modified TIC14 solution was markedly stronger than that without (NH4)2SOg-modified TIC14 solution. Maximal photocatalytic activity was observed at the mole ratio of Ti:(NH4)2SO4= 1:2, the water-bath temperature of 90℃ and the calcination temperature of 700 ℃.  相似文献   

20.
利用酸催化的溶胶-凝胶法制备掺锌的纳米二氧化钛复合材料.采用亚甲基蓝分光光度法对S2-浓度进行测定.通过对纳米复合材料催化剂的不同用量和反应物起始浓度等因素的考察,研究了该催化剂在处理废水中S2-的光催化性能.  相似文献   

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