Titanium Dioxide - Material for a Sustainable Environment最新文献_第3页

Factor Affecting Geometry of TiO2 Nanotube Arrays (TNAs) in Aqueous and Organic Electrolyte 水电解质和有机电解质中TiO2纳米管阵列几何形状的影响因素

Titanium Dioxide - Material for a Sustainable Environment Pub Date : 2018-02-13 DOI: 10.5772/INTECHOPEN.74193

K. A. Saharudin, S. Sreekantan, R. Mydin, N. Basiron, Warapong Krengvirat

引用次数: 3

Photocatalytic Degradation of Selected Organophosphorus Pesticides Using Titanium Dioxide and UV Light 二氧化钛与紫外光光催化降解部分有机磷农药的研究

Titanium Dioxide - Material for a Sustainable Environment Pub Date : 2017-12-20 DOI: 10.5772/INTECHOPEN.72193

A. Petsas, M. Vagi

{"title":"Photocatalytic Degradation of Selected Organophosphorus Pesticides Using Titanium Dioxide and UV Light","authors":"A. Petsas, M. Vagi","doi":"10.5772/INTECHOPEN.72193","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.72193","url":null,"abstract":"The photocatalytic degradation of five selected organophosphorus pesticides (OPPs), azinphos methyl, azinphos ethyl, disulfoton, dimethoate, and fenthion, has been investigated using TiO 2 (photocatalyst) and UV irradiation. The addition of H 2 O 2 (oxidant agent) into the illuminated aquatic suspensions was also surveyed. The degradation kinetics was studied under different experimental conditions such as pesticides’ and catalyst’s concentration. Experiments were performed in a Pyrex UV laboratory-constructed photoreactor equipped with 4 × 18 W low-pressure Hg lamps emitting at 365 nm (maximum intensity 14.5 mW cm −2 at distance 15 cm). The concentration of pesticides was determined by GC-NPD means. The extent of pesticide mineralization was assessed through TOC measurements. The results demonstrated that photolysis of target organophosphates in the absence of catalyst or oxidant is a slow process resulting in incomplete mineralization. Contradictory, studied pollutants were effectively degraded in the presence of TiO 2 ; evolution of inorganic hetero- atoms (SO 4 2− , PO 4 3− , NO 2 − , NO 3 − , and NH 4 + ) as final products provided evidence that pesticide deterioration occurred. The photolysis efficiencies decreased in the order: disulfoton > azinphos ethyl > azinphos methyl > fenthion > dimethoate. Furthermore, a synergistic effect was observed with the addition of H 2 O 2 in the pesticide-TiO 2 suspensions. In all cases examined, reduction process appeared to follow pseudo first-order kinetics (Langmuir-Hinshelwood model). In conclusion, both catalytic systems investigated (UV-TiO 2 and UV-TiO 2 -H 2 O 2 ) have good potential for small-scale applications. into","PeriodicalId":23104,"journal":{"name":"Titanium Dioxide - Material for a Sustainable Environment","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90944438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Influence of the Synthesis Method on the Preparation Composites Derived from TiO2-LDH for Phenol Photodegradation 合成方法对制备TiO2-LDH光降解苯酚复合材料的影响

Titanium Dioxide - Material for a Sustainable Environment Pub Date : 2017-12-20 DOI: 10.5772/INTECHOPEN.72279

J. C. Contreras-Ruiz, S. Martínez-Gallegos, J. L. García-Rivas, J. C. González-Juárez, E. Ordoñez

{"title":"Influence of the Synthesis Method on the Preparation Composites Derived from TiO2-LDH for Phenol Photodegradation","authors":"J. C. Contreras-Ruiz, S. Martínez-Gallegos, J. L. García-Rivas, J. C. González-Juárez, E. Ordoñez","doi":"10.5772/INTECHOPEN.72279","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.72279","url":null,"abstract":"Three different TiO2 catalysts are prepared using different methods. MgAl-CO3 layered double hydroxides (LDH) were obtained by the sol-gel method. In the preparation of the composites, the three photocatalysts were combined with LDH following different methodologies. The composites were characterized using X-ray diffraction (XRD), specific surface area (SA), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The influence of the synthesis method on the preparation of the composites was evaluated by analyzing their photocatalytic activity against phenol as a model organic pollutant under UV irradiation. The photocatalytic activity of the composites improves when the chemical interaction, determined by XPS, between the TiO2 and the LDH decreases. The same happens when the ratio of the anatase-rutile phases, determined by XRD, approaches optimum (80:20%). The effect of the composite concentration in the solution (0.5–2.0 g/L) was investigated, and the light-shielding phenomenon due to high composite concentration decreases the phenol photodegradation. The reduction of photocatalytic activity in reuse cycles is due to loss and partial deactivation of the material. The elimination of phenol is attributed primarily to the photocatalytic process due to the generation of ●OH radicals and to a lesser extent the adsorption process also present in the samples.","PeriodicalId":23104,"journal":{"name":"Titanium Dioxide - Material for a Sustainable Environment","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73005399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Luminescence from TiO2 Nanotubes and Related Nanostructures Investigated Using Synchrotron X-Ray Absorption Near-Edge Structure and X-Ray Excited Optical Luminescence 利用同步加速器x射线吸收近边结构和x射线激发光学发光研究TiO2纳米管和相关纳米结构的发光

Titanium Dioxide - Material for a Sustainable Environment Pub Date : 2017-12-20 DOI: 10.5772/INTECHOPEN.72856

Lijia Liu, T. Sham

引用次数: 2