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The electrogenerated chemiluminescence of highly fluorescent organic chromophores and nanoparticlesOmer, Khalid Mohammad 27 August 2010 (has links)
Electrogenerated chemiluminescence (ECL) of new, highly fluorescent molecules was studied. Six novel, highly fluorescent, green emitters were synthesized by incorporating an acceptor group like 2,1,3-Benzothiadiazole between different donor groups. The structural effects on the electrochemical, spectroscopic, and ECL behavior are shown in detail. Stable electrochemistry and high PL quantum yield were observed. Most of the ECL was visible by the naked eye. Well-known, fluorescent, polyaromatic hydrocarbons (PAH), like 9,10-diphenylanthracene derivatives, pyrene, and anthracene were incorporated between two bulky fluorene derivative groups. The fluorene substitutions block the active positions of the PAH cores, permitting the formation of stable radical ions upon electrochemical oxidation or reduction. Such a tailoring led to increase electrochemical reversibility and tuning of the ECL wavelength. Fluorene-based DPA (FDF) is characterized by a highly efficient and stable blue-cyan color. Another interesting type of molecules was star-shaped structures. The effects of structure on the electrochemistry and spectroscopy of a series of star-shaped, rigid molecules was examined. T1-T4 is composed of oligofluorene arms with truxene as a central core basically there were weak donor and weak acceptors. The ECL quantum efficiency was near 80% for the long-arm T4. One of the interesting goals in ECL is to find ECL emitters in aqueous media. Organic nanoparticles (ONPs) were chosen to achieve this goal. An organic nanoparticle (ONPs) is still challenging area in nanoscience. The key factor of such a challenge comes from the difficulty to control the size and shape of the prepared nanoparticles. ONPs of common hydrocarbon ECL emitters like rubrene and 9,10-diphenylanthracene (DPA) were prepared in aqueous solution using a reprecipitation method. ECL of rubrene NPs was observed when tripropylamine (TPrA) was used as a coreactant, and weaker ECL of DPA NPs was observed when the oxalate ion was used as a coreactant. The ECL of ONPs in aqueous media may open a new field in ECL, allowing the exploration of more phenomena in organic nanoscience. Organic nanoparticle ECL (especially if one able to make small size to be diffused easily) has potential application as a tag for the analysis of biologically interesting molecules. / text
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Electrochemical and electrogenerated chemiluminescence studies of the BODIPY dyesNepomnyashchii, Alexander Borisovich 03 January 2013 (has links)
Electrochemical and electrogenerated chemiluminescence properties of the BODIPY (boron dipyrromethene) dyes are presented. Some specific features of the BODIPY dyes are obtained and described in the current dissertation. Separation of around 1.0-1.2 V is noticed between two oxidation and reduction waves for one center which is very different from 0.5 V seen for the polycyclic hydrocarbons. Cathodic and anodic stability is shown to depend upon absence or presence of certain degree of substitution. Different ways of electrochemical dimerization are explored and compared with the chemical dimerization. Photophysical and electrochemical properties of monomer, chemically synthesized dimer, trimer and polymer are described and the characteristic features determined. / text
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Electrochemistry and electrogenerated chemiluminescence of unique organic chromophores and organic nanoparticlesSuk, Jung Don 27 June 2012 (has links)
Electrogenerated chemiluminescence (ECL) studies were performed on several interesting compounds. A series of BODIPY derivatives was examined to understand the structural effects on the electrochemical, spectroscopic, and ECL behavior. Stable electrochemistry and high fluorescence in the green to the red regions were observed. PB, MCPB, DCPB and PM580 produced intense ECL, strong enough to be seen with the naked eye in a lighted room. Unlike MCPB and DCPB, PB produced the multiple ECL peaks. Totally blocked BODIPY compound showed the improvement of fluorescence and ECL quantum yield due to the stability of radicals. Strong signal of EPR data during the oxidative electrolysis was obtained by simultaneous electrochemical-electron paramagnetic resonance technique with home-made cell. Several new antrhacene derivatives such as a variety of 2- and 4-fold anthracene-functionalized tetraarylbimesityls and a series of 9-naphthylanthracene based dimer and trimer were studied. They showed one wave on the oxidation and reduction because of a sequence, two or more electron transfers during the annihilation of the radical ions. Depended on the structure, some of them exhibited excimer formation on ECL spectra. Azide-BTA compound which consists of two triphenylamine and 2,1,3-benzothiadiazole groups at the ends bridged by a fluorene moiety was synthesized and examined. The compound is a newly synthesized D-A-[pi]-A-D molecule which had reversibility upon electrochemical oxidation and reduction, and also showed intense red fluorescence and stable red ECL emission. Using a simple reprecipitation method, well-dispersed and spherical organic nanoparticles of Azide-BTA and 9-naphthylanthracene based dimer were prepared in an aqueous solution. Controlling the preparation condition, the size of nanoparticles can be minimized to 15 nm. Especially we prepared the organic nanoparticles of 9-naphthylanthracene based dimer dispersed in organic solvent, MeCN, one of the preferred solvents for electrochemical studies and ECL. / text
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In situ reflection absorption spectroscopic techniques for the study of electrogenerated speciesZhao, Ming January 1993 (has links)
No description available.
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Development of wireless DNA microarray sensorsChow, Kwok-Fan 20 October 2011 (has links)
The development of wireless DNA microelectrochemical microarray sensors is described. The operational principles of these sensors are based on bipolar electrochemistry. Bipolar electrodes are used to fabricate the wireless microarrays in this work. The systems are configured so that DNA sensing is carried out at the cathodic end of a bipolar electrode (BPE) and the result of the sensing experiment is reported at the anodic end of the BPE.
There are two types of reporting platforms developed in this study. The first type relies on the emission of electrogenerated chemiluminescence (ECL). The system is configured so that ECL is emitted at the anodic end of the BPE when the target DNA is hybridized to the capture probe DNA immobilized on the cathodic end of the BPE. However, when there is no hybridization reaction occurs, there is no ECL emission on the electrode surface.
The second type of reporting platform developed is based on silver electrodissolution at the anodic end of a BPE. When a reduction reaction occurs at the cathodic end of a BPE, it triggers oxidation and dissolution of silver deposited at the anodic end of the BPE. The loss of silver can easily be detected by the naked eye. This detection principle is used for DNA detection: when the target DNA is hybridized to capture probe DNA on the BPE, the BPE becomes shorter. However, if target DNA does not hybridize to the electrode surface, the length of the BPE remains the same.
The BPE microarrays described in this work eliminate the need for complicated microfabrication procedures and instrumentation. For example, as many as 1000 BPEs can be simultaneously controlled using just two driving electrodes and a simple power supply. To fully utilize BPE microarrays for specific sensing tasks, a method based on robotic spotting was developed to modify the cathodic end of each BPE in the array. Because each BPE in a microarray is individually addressable, this development allows each BPE to perform a particular sensing operation. / text
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Réseaux nanostructurés de fibres optiques pour la réalisation de capteurs électrochimiques et luminescentsAdam, Catherine 29 November 2013 (has links)
La structuration et la fonctionnalisation de réseaux de fibres optiques ont été utilisées afin de réaliser différents capteurs électrochimiques et luminescents. Ce type de support permet de concevoir des capteurs capables de détecter à distance dans un milieu confiné, difficilement accessible ou dangereux. Deux capteurs pour la détection du mercure cationique (Hg2+) sont décrits dans cette thèse. Le premier utilise un dérivé de la rhodamine, qui est lié de façon covalente à la surface en verre du réseau, par silanisation. Le signal fluorescent de cette sonde est augmenté en présence de mercure ce qui permet de le quantifier. Le second capteur combine l’électrochimie sur ces réseaux de fibres optiques, grâce à une fine couche conductrice déposée à sa surface. Le réseau est ensuite modifié avec un complexe de Ruthénium(II), qui peut être électropolymérisé par l’intermédiaire de la fonction cyclopentadithiophène (CPDT). La détection du mercure est alors réalisée par électrochimiluminescence (ECL), qui est collectée à distance, grâce aux propriétés électro-modulables du film polymère. Les réseaux de fibres optiques nanostructurés ont également été utilisés pour la réalisation d’une sonde SECM, présentant un réseau dense de nanoélectrodes collectives. La réalisation d’un tel outil utilise le positionnement basé sur les forces de cisaillement et peut être utilisé pour la structuration de surfaces conductrices ou isolantes par SECM. / The structuration and the functionalisation of optical fiber bundles have been used to design different optical and electrochemical sensors. The use of these tools allows the realisation of sensors for remote detection in a confined environment, which may be dangerous or not easily accessible. Two sensors for the detection of inorganic mercury (Hg2+) are described in this thesis. The first sensor uses a rhodamine derivative, which is covalently functionalized on the surface of the glass optical fibers by silanisation. The fluorescent signal of this probe increases in presence of mercury, which allows its quantification. The second sensor uses the combination of electrochemistry on the optical fiber bundle, thanks to a thin conductive layer deposited on its surface. The bundle is then modified by electropolymerisation of a Ruthenium (II) complex through the cyclopentadithiophene (CPDT) moiety. The detection of mercury is then realised by elecrogenerated chemiluminescence (ECL), which is collected through the optical fiber bundle, thanks to the optical properties of the polymer film. The nanostructured array of optical fibers has also been used to create a new SECM probe composed of a dense nanoelectrode array. Such a tool is obtained through Shearforce positioning and can be used for the structuration of conductive or insulating surfaces by SECM.
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Transparent carbon electrodes for spectroelectrochemical studiesWalker, Erin Kate 13 November 2012 (has links)
This dissertation describes the assessment and use of carbon optically transparent electrodes (C-OTEs) based on pyrolyzed photoresist films (PPFs) as a platform for spectroelectrochemical investigations. C-OTEs are examined for use in UV-Vis spectroelectrochemistry and electrogenerated chemiluminescence and compared to non-transparent glassy carbon (GC) and the conventional transparent electrode indium tin oxide (ITO). Chapter 1 provides a general overview of transparent electrodes, carbon electrodes, and spectroelectrochemistry. Chapter 2 details a UV-Vis spectroelectrochemical investigation of electrogenerated graphitic oxides (EGO) on the surface of the C-OTE in the presence of KCl. X-ray photoelectron spectroscopy and time of flight secondary ion mass spectroscopy are used to determine EGO composition. Several supporting electrolytes are investigated to determine the mechanism of EGO formation. Chapter 3 details experiments to electrochemically access the exciton emission from self-assembled double-walled tubular J-aggregates via electrogenerated chemiluminescence (ECL). Optimization of ECL intensity with respect to the coreactant concentration and the supporting electrolyte pH is performed on opaque glassy carbon electrodes. ECL and fluorescence spectra are compared, and C-OTEs are utilized to determine the source of disagreement between the spectra. Chapter 4 describes the preparation and characterization (i.e. transparency, thickness, sheet resistance, rms roughness, and electroactive surface area) of C-OTEs and explores C-OTEs for general use in ECL under a variety of conditions. Simultaneous cyclic voltammograms and ECL transients are obtained for three thicknesses of PPFs and compared to non-transparent GC and the conventional transparent electrode ITO in both front face and transmission electrode cell geometries. Despite positive potential shifts in oxidation and ECL peaks, attributed to the internal resistance of the PPFs that result from their nanoscale thickness, the PPFs display similar ECL activity to GC, including the low oxidation potential observed for amine coreactants on hydrophobic electrodes. Overall, C-OTEs are promising electrodes for spectroelectrochemical applications because they yield higher ECL than ITO in both oxidative-reductive and reductive-oxidative ECL modes, are more stable in alkaline solutions, display a wide potential window of stability, and have tunable transparency for more efficient detection of light in the transmission cell geometry. Future directions for this research are discussed in Chapter 5, which outlines several approaches to designing and improving spectroelectrochemical sensors. / text
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Electrogenerated chemiluminescence : from mechanistic insights to bioanalytical applications / Electrochimiluminescence : de la compréhension mécanistique aux applications bioanalytiquesSentic, Milica 26 November 2015 (has links)
La chimiluminescence électrogénérée (ECL) est une technique analytique puissante exploitée pour la détection autant au niveau industriel que dans le domaine de la recherche scientifique ou du diagnostic clinique. La sensibilité élevée et la bonne sélectivité de cette technique font de l'ECL une méthode analytique de choix pour un large éventail d'applications, dont la plus importante est son utilisation commerciale dans un grand nombre de tests immunologiques à base de billes fonctionnalisées. Dans cette thèse, nous avons cherché à étudier le phénomène ECL et son application pour le développement de nouvelles techniques analytiques.Dans la première partie de ce travail, nous utilisons les techniques d'imagerie pour étudier les mécanismes ECL se produisant sur les billes utilisées pour les tests immunologiques. La cartographie de la réactivité au niveau d'une seule microparticule fonctionnalisée avec un complexe de ruthénium fournit une nouvelle stratégie visant à tester l'efficacité du co-réactif et montre des effets optiques associés de focalisation.Dans la deuxième partie, la conception d'un test immunologique pour la détection de l'anti-transglutaminase pour le diagnostic de la maladie coeliaque est présentée en utilisant des ensembles de nanoélectrodes comme plates-formes bioélectroanalytiques. Nous avons également étudié les caractéristiques de l'ECL générée par des réseaux de nanoélectrodes dopées au bore-diamant en tant que matériaux prometteurs pour des applications biologiques ainsi que l'efficacité ECL de deux co-réactifs sur ces réseaux.L'électrochimie bipolaire est un processus sans contact que nous avons exploité pour contrôler le mouvement d'objets conducteurs exposés à un champ électrique en l'absence de contact ohmique direct. Dans la troisième partie de ma thèse, nous présentons l'ECL couplée à l'électrochimie bipolaire pour le suivi d’objets autonomes luminescents. Nous avons élargi ce concept à la détection enzymatique dynamique de glucose en utilisant l'émission de lumière ECL comme signal analytique. / Electrogenerated chemiluminescence (ECL) is a powerful analytical technique exploited for clinical, industrial and research applications. The high sensitivity and good selectivity, makes ECL a tool-of-choice analytical method for a broad range of assays, most importantly for a large number of commercialized bead-based immunoassays. In the present thesis, we aimed to study the ECL phenomenon and its application in development of new analytical methods.In the first part of this work, we used an imaging technique to investigate the ECL mechanisms operating in bead-based assays. Spatial reactivity mapping at the level of a single functionalised bead provides a new strategy to test the co-reactant efficiency and shows associated optical focusing effects.In the second part, the design of a novel anti-transglutaminase ECL immunoassay for celiac disease diagnostic is shown using nanoelectrode ensembles as bioelectroanalytical platforms. We also studied the characteristics of ECL generated by arrays of boron-doped-diamond nanoelectrodes (BDD NEAs) as a promising materials for bioapplications. The ECL efficiency of two co-reactants at BDD NEAs was investigated.Finally, bipolar electrochemistry is a ‘‘wireless’’ process that was exploited for the controlled motion of conductive objects exposed to an electric field in the absence of direct ohmic contact. In the third part of the thesis, we report ECL coupled to bipolar electrochemistry for tracking the autonomous trajectories of swimmers by light emission. We further expanded this concept for dynamic enzymatic sensing of glucose concentration gradient using ECL light emission as an analytical readout.
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Immobilisation d'hydrogel redox pour la détection par électrochimiluminescence / Electrogenerated chemiluminescence detection based on advanced immobilised redox hydrogelMilutinovic, Miléna 16 December 2011 (has links)
Ce travail de thèse a pour objectif l’étude de l’électrochimiluminescence (ECL) et son application pour le développement de nouvelles techniques analytiques. De par son importante sensibilité, l’ECL est une technique performante pour des applications telles que les diagnostics cliniques ou la chimie environnementale (présence d’agents contaminants dans l’eau ou la nourriture). L’immobilisation du luminophore ECL est réalisée généralement sur une phase solide. Cette étape constitue une phase essentielle pour obtenir une méthode d’immobilisation rapide, simple, flexible et efficace de ces luminophores ECL, tout en permettant une utilisation pour des systèmes variés. La première partie de ce travail présente l’optimisation de la déposition électrochimique de films de métallopolymère de ruthénium et son application pour la détection enzymatique. Un film d'épaisseur micrométrique de cet hydrogel redox a été préparé par voltamétrie cyclique. Cet hydrogel immobilisé a permis la détection d’un substrat modèle (le glucose) en utilisant l'enzyme glucose déshydrogénase. La seconde partie se concentre sur le développement d’une nouvelle méthode de photodéposition d’un polymère. Celle-ci permet l’immobilisation de centres actifs sur des régions sélectives. En utilisant les techniques de photolithographie, les figures du masque sont projetées sur la surface des électrodes. Cela permet la réalisation de spots micrométriques dont la taille, forme et épaisseur sont modulables. Les propriétés électrochimiques des films nanométriques obtenus sont comparables à ceux obtenues par électrodéposition. De même, les spectres ECL réalisés avec polymères immobilisés par ces deux stratégies sont identiques. Ces résultats montrent que les états excités induits lors de l’ECL sont identiques avec les deux techniques d’immobilisation. Le développement d'un tel procédé constitue une alternative prometteus pour la réalisation de réseaux de spots ECL différenciés et permettant la détection multipléxée par imagerie ECL. Dans la troisième partie de ce travail, nous avons associé la spectroélectrochimie et l'imagerie ECL pour contribuer à l’étude des mécanismes ECL au niveau d'une bille micrométrique fonctionnalisée par des complexes de ruthénium. En combinant microscopie de fluorescence et imagerie ECL, la distribution des sites électroactifs et des sites ECL a pu être mise en évidence. A partir de cette étude, nous pouvons clarifier les mécanismes conduisant à l'émission ECL au niveau de ces billes fonctionnalisées. / The main goal of this thesis was to study electrogenerated chemiluminescence (ECL) and its application in development of new analytical techniques. Due to its high sensitivity, ECL presents a powerful method for applications in clinical diagnostic and environmental chemistry (presence of contaminants in water or food). The immobilisation of an ECL luminophore is usually performed on a solid phase. This step is an essential point to obtain a technique for fast, simple, flexible and effective immobilisation of ECL luminophores with possibility of applications in various configurations. The first part of this work presents the optimisation of the electrochemical deposition of a ruthenium metallopolymer and its application in enzymatic detection. A redox hydrogel film with micrometric thickness was prepared using cyclic voltammetry. This immobilised hydrogel allows the detection of model substrate (glucose) using enzyme glucose dehydrogenase. The second part of this thesis is focused on the development of a new photodeposition method for the ECL polymer immobilisation. This method allows region-selective immobilisation of active centres. Using photolithographic methods, the figures from the mask are projected on the electrode surface. This allows the formation of micrometric spots which size, shape and thickness is modulated. Electrochemical properties of obtained nanometric films are comparable with those of electrodeposited films. Also, ECL spectra recorded with both immobilisation strategies are identical. It shows that the ECL excited state is the same. The obtained photopatterns were imaged using ECL. The development of such process presents an alternative for realisation of different ECL spot arrays and allows multiplexed detection by ECL imaging. In the third part of this work we have associated spectroelectrochemistry and ECL imaging to study the ECL mechanisms at the level of a single microbead, functionalised with ruthenium complex. Combining fluorescence microscopy and ECL imaging, the distribution of electroactive and ECL sites have been highlighted. From this study we can clarify the mechanism that leads to ECL emission at the level of functionalised beads.
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Degradação eletroquímica/química dos corantes têxteis Reativo Azul 19 e Reativo Preto 5 utilizando eletrodos de diamante dopado com boro e H2O2 eletrogerado em eletrodo de carbono vítreo reticulado / Electrochemical/chemical degradation of textile dyes Reactive Blue 19 and Reactive Black 5 using boron doped diamond electrodes and H2O2 electrogenerated in reticulated vitreous carbon electrodeVasconcelos, Vanessa Moura 11 September 2015 (has links)
A problemática envolvendo os efluentes têxteis decorre principalmente da elevada coloração que apresentam, devido à presença de corantes que além de serem quimicamente estáveis, podem ser tóxicos e/ou carcinogênicos. Logo, quando são descartados in natura no meio ambiente causam problemas estéticos e, sobretudo, ambientais mesmo em baixas concentrações, além da possibilidade de serem nocivos à saúde humana e dos animais. Neste contexto, o objetivo deste trabalho foi estudar a degradação eletroquímica de dois corantes têxteis, Reativo Azul 19 (RA-19) e o Reativo Preto 5 (RP-5) via Oxidação Anódica (OA), utilizando ânodos de Diamante Dopado com Boro (DDB) suportados em titânio ou em nióbio, via processo Eletro-Fenton (EF) e pela combinação dos processos com H2O2 eletrogerado e OA (CP), usando um eletrodo de Carbono Vítreo Reticulado (CVR) como cátodo. As degradações foram realizadas em célula eletroquímica de um compartimento e em reator de fluxo do tipo filtro-prensa com dois compartimentos. A eficiência das degradações foi monitorada pelas técnicas de espectrofotometria no UV-VIS, Cromatografia Líquida de Alta Eficiência (CLAE) e análise do teor de Carbono Orgânico Total (COT). As variáveis estudadas foram densidade de corrente (10-100 mA cm-2 em célula e 4-41 mA cm-2 em reator), dopagem do eletrodo de DDB/Ti (5.000 e 15.000 ppm B/C), concentração inicial dos íons Fe2+ (0-0,10 mmol L-1) e dos corantes (10-250 mg L-1). As degradações dos corantes apresentaram uma cinética de pseudo ordem zero; exceto quando o corante RP-5 foi degradado pelo processo EF, sendo o melhor ajuste ao modelo de pseudo primeira ordem. Além disso, em iguais condições eletroquímicas o corante RP-5 foi degradado em menor tempo em relação ao RA-19; sendo que em todos os processos estudados os corantes foram totalmente removidos. Considerando a OA em célula com os eletrodos de DDB/Ti, a degradação foi positivamente influenciada pelo aumento da densidade de corrente e dopagem do eletrodo, especialmente em relação a cinética. Além disso, os corantes RA-19 e RP-5 foram completamente removidos em 35 e 50 min de eletrólise quando 100 mA cm-2 foi aplicada ao eletrodo de DDB/Ti dopado com 15.000 ppm relação B/C. Em 2 h, 37% em mineralização foi observado para ambos os corantes e a toxicidade do RA-19 diminuiu contra as bactérias Vibrio fischeri. Ainda nessa condição total mineralização foi alcançada após 8 h de degradação. A remoção de COT foi favorecida utilizando o reator contendo os eletrodos de DDB/Nb e CVR ao invés da célula eletroquímica, chegando a percentuais de 84 e 82% em 30 e 90 min para os corantes RA-19 e RP-5 que foram removidos em 7,5 e 5 min, respectivamente, quando a densidade de 41 mA cm-2 foi aplicada ao DDB/Nb durante a degradação via exclusivamente OA. Entre os processos realizados no reator, o EF foi o energeticamente mais favorável, promovendo remoção em COT de 60 e 74% para os corantes RA-19 e RP-5 com consumo energético de 204 e 208 kWh kg-1, além disso, a completa remoção dos corantes ocorreu em 15 e 7,5 min, respectivamente, quando o eletrólito continha íons Fe2+ na concentração de 0,10 mmol L-1 e aplicando-se -0,4 V vs Ag/AgCl ao eletrodo de CVR. Na degradação os corantes via CP o RA-19 e RP-5 foram completamente removidos em 30 e 15 min com mineralização de 72 e 82% em 90 min associada a consumos energéticos de 562 e 745 kWh kg-1, respectivamente, quando 41 mA cm-2 foi aplicada ao DDB/Nb. Por fim, concluiu-se que os resultados das degradações dos corantes foram promissores, já que rápida remoção dos corantes foi observada, além da parcial mineralização. Logo os processos propostos podem ser aplicados na remoção dos corantes em água; sendo necessários realizar mais estudos, principalmente em relação ao material eletródico e configuração do sistema eletroquímico visando a aplicação industrial. / The main problem involving the textile wastewater is theirs high coloration since they present dyes, which are chemically stable and can be toxic and/or carcinogenic. Therefore, when the textile wastewater are discarded in nature in the environment, even in low concentrations, they may cause not only aesthetic and environmental problems, but also can be harmful to human and animal health. In this context, the aim of the study was to evaluate the electrochemical degradation of two textile dyes, Reactive Blue 19 (RB-19) and Black 5 (RB-5) via Anodic Oxidation (AO) using as anodes Boron Doped Diamond electrodes (BDD) supported on titanium or niobium, via Electro-Fenton (EF) process and by combination of processes with electrogenerated H2O2 and AO (CP) using a Reticulated Vitreous Carbon electrode (RVC) as cathode. The degradations assays were carried out in an electrochemical cell with one compartment and in a filter-press flow reactor with two compartments. The efficiency of degradation was monitored by UV-VIS spectrophotometry, High Performance Liquid Chromatography (HPLC) and analysis of Total Organic Carbon (TOC). The variables studied were current density (10-100 mA cm-2 for cell and 4-41 mA cm-2 for reactor), doping of the BDD/Ti electrodes (5,000 e 15,000 ppm B/C), initial concentration of the Fe2+ ions (0-0,10 mmol L-1) and dyes (10-250 mg L-1). The kinetic results showed that the removal of dyes followed the model of pseudo zero order; except when the RB-5 dye was degraded by EF process, which the best fitted was to pseudo first order model. Furthermore, for equal conditions the RB-5 was degraded in less time in comparison to the RB-19. In addition, the dyes were fully removed in all the processes studied. Regarding the AO in cell with BDD/Ti, the degradation was positively influenced by the increasing in current density and doping of the electrode, primarily the kinetics parameters. In addition, total removal of RB-19 and RB-5 was achieved in 35 and 50 min of electrolysis when 100 mA cm-2 was applied to the electrode doped with 15,000 ppm ratio B/C. In 2 h, 37% in mineralization was attained for both dyes and the toxicity effect of the RB-19 decreased against the bacteria Vibrio fischeri. In this condition, total TOC removed was also reached after 8 h. The TOC removal was enhanced using the reactor fitted with BDD/Nb and RVC instead of the electrochemical cell, achieving TOC removal of 84 and 82% in 30 and 90 min for RB-19 and RB-5 which were removed in 7.5 and 5 min, respectively, when 41 mA cm-2 was applied to the BDD/Nb in the degradation exclusively via AO. Among the processes carried out in the reactor, the EF was the energetically most favourable since TOC removal of 60 and 74% for RB-19 and RB-5 with energy consumption of 204 and 208 kWh kg-1 were noted. In addition, the RB-19 and RB-5 were completely removed in 15 and 7.5 min, respectively, when the electrolyte containing 0.10 mmol L-1 of Fe2+ ions and -0.4 V vs Ag/AgCl was applied to CVR electrode. The combination of processes with electrogenerated H2O2 and AO for degradation of the dyes removed the RB-19 and RB-5 in 30 and 15 min with mineralization of 71.6 and 81.8% in 90 min associated to energy consumptions of 562 and 745 kWh kg-1 respectively, when 41 mA cm-2 was applied to BDD/Nb. Therefore, the degradation results of the dyes were promised since quickly removal of the dyes and partial mineralization were observed hence the proposed processes could be used to remove the dyes from water. However, more studies are needed to enable an industrial application, especially regarding the electrode material and configuration of the electrochemical system.
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