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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Desenvolvimento e validaÃÃo de um mÃtodo analÃtico (SPEâHPLC) para determinaÃÃo de compostos emergentes em Ãguas superficiais. / Development and validation of an analytical method (SPE- HPLC) for determination of emerging compounds in surface waters

Sarah de Abreu Moreira AraÃjo 31 January 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Poluentes orgÃnicos emergentes (POEs) ou simplesmente contaminantes emergentes referem-se a qualquer composto quÃmico presente numa variedade de produtos comerciais como medicamentos, produtos de uso veterinÃrio, embalagens de alimentos, produtos de higiene, agrotÃxicos, ou alguns microrganismo. Os POEs podem ser encontrados em matrizes ambientais e biolÃgicas, nÃo sÃo usualmente monitorados ou ainda nÃo possuem legislaÃÃo regulatÃria correspondente, e apresentam risco potencial à saÃde humana e ao meio ambiente. Neste trabalho, foi desenvolvido e validado um mÃtodo para a determinaÃÃo de cafeÃna, ciprofloxacina, 17β-estradiol, 17α-etinilestradiol e dietilestilbestrol, considerados interferentes endÃcrinos. O mÃtodo desenvolvido utilizou extraÃÃo em fase sÃlida (SPE) e cromatografia lÃquida de alta eficiÃncia acoplada a um detector de arranjo de diodos. Foram estabelecidas condiÃÃes cromatogrÃficas com eluiÃÃo por gradiente utilizando acetonitrila e Ãgua ultrapura pH 2,0. O planejamento fatorial realizado por SPE indicou que melhores respostas sÃo alcanÃadas quando utiliza-se o cartucho C18, 500 mL de volume de amostra, pH 3,0 e volume de eluiÃÃo igual a 2,0 mL de metanol 100%. As figuras de mÃrito de validaÃÃo do mÃtodo indicaram seletividade, sensibilidade, linearidade, precisÃo, exatidÃo e robustez satisfatÃrias para a maioria dos compostos estudados. Os limites de detecÃÃo (LD) variaram entre 0,283 e 1,543 μg/L (ppb) e os limites de quantificaÃÃo (LQ) variaram entre 0,944 e 5,142 μg/L (ppb). Foi proposta uma nova estratÃgia de controle de qualidade utilizando padrÃo surrogate, e estabelecido um fator de relaÃÃo (FR) a fim de corrigir as concentraÃÃes dos compostos de interesse em amostras reais. O mÃtodo validado foi aplicado nas anÃlises de Ãgua superficial dos aÃudes que fazem parte do abastecimento de Ãgua da RegiÃo Metropolitana de Fortaleza/CE. Os compostos 17β-estradiol, 17α-etinilestradiol foram detectados numa concentraÃÃo mÃxima de 989 e 980 ng/L, respectivamente. / Emerging organic pollutants (EOP), or Emerging Contaminants, is a term that is used to refer any chemical compound insert in variety of comercial products such as medicines, veterinary products, food packaging, pesticides, or any microorganism. The EOP can be found in environmental and ecological arrays not usually monitore or government unregulated, and poses risks to human health na environment. The methodological approach of this thesis included a developed and validated method to determine caffeine, ciprofloxacin, 17β-estradiol, 17α-ethinylestradiol and diethylstilbestrol, considered endocrine disruptors. The method uses a Solid-Phase Extraction (SPE) and high performance liquid cromatography coupled to a diode array detector. Chromatografic conditions were established by gradiente elution using acetonitrile and ultrapure water (pH = 2). The experimental design performed by SPE showed that better responses are achieved when it is used the cartridge C18, 500 mL sample volume, pH 3,0 and 2,0 mL 100% methanol elution volume. The method validation parameters indicated satisfatory selectivity, sensitivity, linearity, precision, accuracy and robustness. Detection limits (DL) ranged from 0,283 to 1,543 μg/L (ppb) and quantification limits (QL) ranged from 0,944 e 5,142 μg/L (ppb). A new quality control strategy using surrogate standard was proposed, and a relation factors (RF) was established to correct of concentrations of compounds of interest in real samples. The validated method was applied to the analysis of surface waters reservoirs from water supply system in metropolitan region of Fortaleza. The compounds 17β-estradiol, 17α-ethynyl estradiol was detected in a maximum concentration of 989 to 980 ng / L, respectively.
2

Analyse prédictive du devenir des médicaments dans l'environnement / Predictive analysis of the fate of pharmaceuticals in the environment

Laurencé, Céline 05 December 2011 (has links)
Les substances pharmaceutiques sont classées comme contaminants environnementaux émergents et suscitent une attention croissante du fait de leurs effets potentiellement néfastes sur les écosystèmes. Après excrétion ou élimination inappropriée, les médicaments vont se retrouver dans les eaux de surface, souterraines voire de consommation. De nombreuses études écotoxicologiques ont pour objet la mesure de leurs impacts sur les écosystèmes. Pour autant, ces études portent essentiellement sur le médicament lui-même alors que nombre d'entre eux sont susceptibles de se transformer dans l'environnement selon des processus biotiques (microorganismes) et/ou abiotiques (traitements chimiques, photodégradation). Les produits de transformations (PTs) ainsi formés vont d'une part, progressivement remplacer le médicament parent dans l'environnement, et d'autre part y exprimer une écotoxicité potentielle. Face à ce problème, nous nous proposons à partir d'un médicament largement utilisé, de procéder à la synthèse de ses PTs plausibles et à la mise au point de méthode de détection dans des matrices complexes. L'accès aux PTs suivra une approche pluridisciplinaire faisant appel à la bioconversion, l'électro-Fenton et l'oxydation électrochimique. L'analyse comparative des composés obtenus par ces différentes approches permettra de sélectionner les PTs les plus probables / Pharmaceuticals as well as personal care products are classified as emerging pollutants of increasing concern due to possible negative impacts on ecosystems. They are constantly introduced in sewage treatment plants either through excretion, or disposal by flushing of unused or expired medication, or directly within the sewage effluents of plants or hospitals. They end up in surface and ground waters and can even be found in drinking water. Many studies report on adverse effects on terrestrial and aquatic organisms. Pharmaceuticals have complex chemical structures capable of reacting in an aqueous medium under the action of chemical, biological or physical agents. Thus, the transformation products (TPs) gradually replace the parent drug in the environment. In addition these transformation products constitute markers of past or current presence of the drug in the environment. Faced with this problem, we believe it is necessary to synthesize the transformation products of the parent compounds to development their detection. The proposed method consists, firstly, to prepare the largest number of (TPs) of a particular drug using three complementary approaches : bioconversion, electro-Fenton and electrochemical oxidation. A second step is to identify the structures which are the most likely present in the environment. Expected advances are the development of a predictive methodology applicable to the study of any molecule involved in environmental risk
3

Estudo de eletrodegrada??o de poluentes emergentes em c?lulas eletroqu?micas do tipo eletr?lito polim?rico s?lido

Castro J?nior, Jos? Geraldo Mendes 29 August 2017 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-03-08T18:31:35Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) jose_geraldo_mendes_castro_junior.pdf: 20723597 bytes, checksum: f867ab4f1cb9235c24c8c6d16d42c22c (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-03-09T18:46:17Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) jose_geraldo_mendes_castro_junior.pdf: 20723597 bytes, checksum: f867ab4f1cb9235c24c8c6d16d42c22c (MD5) / Made available in DSpace on 2018-03-09T18:46:17Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) jose_geraldo_mendes_castro_junior.pdf: 20723597 bytes, checksum: f867ab4f1cb9235c24c8c6d16d42c22c (MD5) Previous issue date: 2017 / Eletrodos de di?xido de chumbo (PbO2) suportados sobre tecido de carbono e tela de a?o inoxid?vel foram utilizados na degrada??o eletroqu?mica dos f?rmacos paracetamol (PCT) e dipirona (DPN), utilizando-se uma c?lula eletroqu?mica do tipo eletr?lito polim?rico s?lido (EPS) munida de eletrodos perme?veis a fluidos (EPFs). Todos os estudos foram conduzidos na condi??o de batelada empregando-se a ?gua livre de eletr?litos. Os estudos eletroqu?micos de degrada??o dos f?rmacos foram conduzidos em fun??o da densidade de corrente aparente (jap) (ex., 5, 10, 20, 100, 150 e 200 mA cm-2) e da concentra??o inicial (ex., 10, 30 e 50 mg L 1). As amostras tratadas foram analisadas pelas t?cnicas de espectrofotometria na regi?o do UVVis, cromatografia l?quida de alta efici?ncia (CLAE) e demanda qu?mica de oxig?nio (DQO). Verificou-se para os diferentes casos envolvendo as baixas densidades de corrente que a remo??o das bandas de absor??o no UV-Vis, a remo??o da concentra??o dos f?rmacos (CLAE) e a redu??o da DQO (grau de mineraliza??o) n?o foram significativos. Contrariamente, no caso das elevadas densidades de corrente evidenciou-se uma significante melhora na degrada??o dos f?rmacos em decorr?ncia da atua??o do oz?nio gerado eletroquimicamente. Os melhores resultados foram obtidos para baixas concentra??es dos f?rmacos. Redu??es superiores a 95 % de DQO para o PCT e superiores a 75 % para a DPN foram obtidas. Eletrodos de PbO2 dopados com n?quel (ex., Ni-PbO2) suportados sobre tecido de carbono e tela de a?o inoxid?vel foram confeccionados e caracterizados. A an?lise de microscopia eletr?nica de varredura (MEV) revelou o aparecimento de defeitos superficiais, com a varia??o da concentra??o nominal do Ni no banho eletrol?tico utilizado no preparo do eletrodo por eletrodeposi??o. An?lises de difratometria de raios-X (DRX) corroboraram os resultados de MEV revelando, em alguns casos, picos mais alargados e de menor intensidade (ex., redu??o no tamanho m?dio dos cristalitos) com a varia??o da concentra??o nominal do Ni, indicando assim uma interfer?ncia no processo de eletrodeposi??o do PbO2. Curvas de polariza??o em condi??es quaseestacion?rias foram obtidas para o processo eletr?dico da rea??o de desprendimento de oxig?nio (RDO) sendo verificado que n?o houve influ?ncia significativa do dopante sobre esta rea??o, a qual ocorre em paralelo ao processo de degrada??o oxidativa dos f?rmacos. Verificou-se que a produ??o de oz?nio foi ligeiramente favorecida em algumas concentra??es do dopante e em altas densidades de corrente. No entanto, n?o foi verificada influ?ncia significativa sobre o grau de mineraliza??o dos f?rmacos PCT e DPN mediante uso de eletrodos dopados com Ni. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Lead dioxide (PbO2) electrodes supported on carbon cloth and stainless-steel mesh substrates were used in the electrochemical degradation of the drugs paracetamol (PCT) and dipyrone (DPN), using a solid polymer electrolyte electrochemical cell (SPE) having fluid-permeable electrodes (FPEs). All studies were conducted in batch condition using the electrolyte-free water. The electrochemical degradation of the drugs was accomplished as a function of the apparent current density (ex., 5, 10, 20, 100, 150 and 200 mA cm-2) and the initial concentration (ex., 10, 30 and 50 mg L-1). The treated samples were analyzed using the UV-Vis spectrophotometry technique, the high-performance liquid chromatography (HPLC), as well as the chemical oxygen demand (COD). For the different cases involving the application of low current density values, it was not verified significant changes accounting for the removal of the UV-Vis absorption band, the drug concentration (HPLC), and the COD decrease (ex., the degree of mineralization). In contrast, in the case of high current densities, a significant improvement in the degradation of the drugs was evidenced as a result of the influence of the electrochemically generated ozone. The best findings were obtained for low drug concentrations. Reductions of above 95% COD for PCT and above 75% for DPN were obtained. Nickel-doped PbO2 electrodes (ex., Ni-PbO2) supported on carbon cloth and stainlesssteel mesh were fabricated and characterized. Scanning electron microscopy (SEM) revealed the appearance of surface defects with a reduction in crystal size with the different Ni concentration in the electrolytic bath used to prepare the electrode by electrodeposition. X-ray diffraction (XRD) analyzes corroborated with the SEM results revealing the formation of broader peaks with lower intensity, in some cases, (ex., reduction in the average crystallite size) with the variation of the nominal dopant concentration in the electrolytic bath, thus indicating an interference in the electrodeposition process for PbO2. Quasi-stationary polarization curves were obtained for the electrode process of the oxygen evolution reaction (OER) and it was verified that there was no significant influence of the dopant on this reaction, which occurs in parallel to the process comprising the oxidative degradation of the drugs. It was found that the ozone generation was slightly favored in some concentrations of the dopant and in higher current densities. However, no significant influence was verified on the degree of mineralization of PCT and DPN by the use of Ni-PbO2 electrodes.
4

Síntese e caracterização de nanopartículas de ZnO obtidas por calcinação de nanofios eletrofiados para possivel aplicação como fotocatalisadores / Synthesis and characterization of ZnO nanoparticles obtained by calcination of nanowires obtained by electronspinning for use as catalysts in waste degradation

Silva, Alessandra Eugênio Carli da 22 March 2018 (has links)
Submitted by Marilene Donadel (marilene.donadel@unioeste.br) on 2018-06-07T20:50:15Z No. of bitstreams: 1 Alessandra_Silva_2018.pdf: 2406267 bytes, checksum: fdec397e3ca9dc1b624c4be16eda7aac (MD5) / Made available in DSpace on 2018-06-07T20:50:15Z (GMT). No. of bitstreams: 1 Alessandra_Silva_2018.pdf: 2406267 bytes, checksum: fdec397e3ca9dc1b624c4be16eda7aac (MD5) Previous issue date: 2018-03-22 / The presence of medicines in potable water is one of the biggest concernings in public health, once that there is not a lot knownledge about their chronical effects in a long term intake. The potential risk of contamination in the supplied water has motivated new researches aiming the increasing of the efficiency on removing these emerging pollutants. Among these researches the photocathalysis has widelly been studied due its efficiency on decontaminating chemical pollutants, effluents treatment and residual water purification. Photochemical processes presents positive results on the degradation of organic pollutants compounds and the possibility of obtaining photocataliysts in nanometric scales through the electrophase makes it even more efficient. In this work, by electrophase, was obtained a polimeric solution containing PBAT/ZnO, ZnO particlules with reduced scales. The charcterization of the synthetized material was made by X-Ray Difraction (XRD), Differential Thermal Analysis (DTA) Differential Scanning Calorimetry (DSC), Scanning Electronic Microscopy (SEM) and UV-Vis Spectrophotometry. From the obtained results it was possible to conclude that, the reduced distance between the needle and the collector and electric tension used during the electronspinning of ZnO/PBAT nanowires, influency on getting fibres with smaller diameters, from which there is a possibility of obtaining nanoparticles of ZnO, with mean diameter of 46,96 nm, in its crystalline characteristic phase and equivalent to the commercial material by the electrophased process, however, with the smaller particules, which suggests that with the increasing of the contact surface the compound to be oxidized, the phocatalysis process may be favored. / A presença de fármacos em água potável e de abastecimento é uma preocupação de saúde pública, visto que pouco se sabe sobre os efeitos crônicos do consumo ao longo prazo desses contaminantes. O potencial risco de contaminação da água de abastecimento, tem incentivado estudos com o objetivo de aumentar a eficiência na remoção desses poluentes emergentes. Dentre esses estudos, a fotocatálise vem sendo amplamente estudada devido a sua eficiência na descontaminação ambiental, redução, degradação, remediação ou transformação de resíduos químicos poluentes, tratamento de efluentes e purificação de águas residuárias. Os processos fotoquímicos apresentam bons resultados na degradação de compostos poluentes orgânicos e a possibilidade de obter fotocatalisadores em escala nanométrica através da técnica da eletrofiação pode torná-la ainda mais eficiente. Neste trabalho foi obtido através da eletrofiação de uma solução polimérica contendo PBAT/ZnO partículas de ZnO com escala reduzida. A caracterização do material sintetizado foi realizada por Microscopia Optica, Difração de Raios-X (DRX), Análise Térmica Gravimétrica (TGA), Calorimetria Exploratória Diferencial (DSC), Microscopia Eletrônica de Varredura (MEV) e Espectrofotometria UV-Vis. A partir dos resultados obtidos foi possível concluir que, a diminuição da distância entre a agulha e o coletor e tensão elétrica utilizadas durante a eletrofiação dos nanofios de ZnO/PBAT, influencia na obtenção de fios com diâmetros menores e que a partir destas fibras há possibilidade de obtenção de nanopartículas de ZnO, com diâmetro médio de 46,69 nm, com fase cristalina característica e equivalente ao material comercial, porém com tamanho de partículas menores, o que sugere aumento da superfície de contato do material particulado com o composto a ser oxidado, favorecendo o processo de fotocatálise.
5

Ozonation des concentrats de nanofiltration dans le cadre de la réutilisation des eaux usées urbaines / Ozonation of nanofiltration concentrates within the framework of the reuse of domestic wastewaters.

Azaïs, Antonin 17 December 2015 (has links)
La croissance démographique mondiale induit une pression accrue sur les ressources en eau potable. Une des solutions pour répondre à cette problématique environnementale est de réutiliser les eaux en sortie de station d’épuration (STEP). Cependant, la présence de microorganismes pathogènes et de micropolluants bio-récalcitrants et potentiellement toxiques ne permet pas une réutilisation directe des effluents urbains. Les procédés membranaires peuvent alors être envisagés afin d’éliminer efficacement ces polluants à l’état de trace. Cependant, la mise en œuvre des procédés membranaires implique la production de retentâts concentrés en micropolluants dont le traitement n’est, à ce jour, pas envisagé. Cette thèse propose alors d’étudier l’ozonation pour le traitement de retentâts de nanofiltration (NF) dans le cadre de la réutilisation des eaux usées, l’ozone étant un puissant oxydant et précurseur de radicaux hydroxyles. Pour cela, quatre micropolluants pharmaceutiques ont été sélectionnés comme molécules cibles. Par la suite, l’étude de la NF a mis en évidence qu’elle peut constituer une alternative viable au standard industriel qu’est l’osmose inverse en assurant des rétentions élevées pour des coûts opératoires moindres. L’ozonation s’avère efficace comme prétraitement des concentrâts en éliminant totalement les polluants les plus réactifs à l’ozone moléculaire. Toutefois, ce procédé reste limité quant à l’abattement des polluants réfractaire à l’ozone du fait de l’inhibition de la voie radicalaire par la forte teneur en matière organique des retentâts. Finalement, bien que cette association de procédés soit prometteuse, un traitement supplémentaire en aval de l’ozonation serait nécessaire afin de permettre la réutilisation des retentâts traités et aboutir à l’avènement d’une filière épuratoire à zéro rejet liquide / Global population growth induces increased threat on drinking water resources. One way to address this environmental issue is to reuse water from wastewater treatment plant (WWTP). However, the presence of pathogenic microorganisms and potentially toxic organic micropollutants does not allow a direct reuse of urban effluents. Membrane processes such RO or NF can be considered to effectively eliminate these pollutants. However, the integration of membrane processes involves the production of concentrated retentates which require to be disposed. To date, no treatment is set up to manage safely this pollution. This thesis project focuses on the application of ozonation for the treatment of NF retentates in the framework of the wastewater reuse. Ozonation is a powerful oxidation process able to react and degrade a wide range of organic pollutants. Four pharmaceutical micropollutants frequently detected in wastewater, were selected as target molecules. This study highlighted that NF can represent a viable alternative to the commonly used reverse osmosis process ensuring high retention at much lower operating costs. Ozonation appear to be effective to degrade the most reactive pollutants toward molecular ozone. However, this method is limited for the reduction of refractory ozone pollutants due to the inhibition of the radical chain by the high content of organic matter in the retentates. Finally, the ozonation processe appear to be a promising NF retentate treatment and further processing downstream of ozonation should allow reuse of treated retentates and lead to the emergence of a zero liquid discharge treatment scheme.
6

Dynamique de polluants émergents (parabènes, triclosan et triclocarban) dans le continuum eaux grises - milieu récepteur. / Dynamics of emerging pollutants (paraben, triclosan, triclocarban) in the continuum greywater - surface water.

Zedek, Sifax 12 December 2016 (has links)
Cette thèse, intégrée dans le projet Cosmet’eau et la phase 4 du programme OPUR, apporte de nouveaux éclairages sur la dynamique des parabènes, du triclosan et du triclocarban en milieu urbain sous forte pression anthropique. Ces molécules sont des biocides couramment utilisés en tant que conservateur dans de très nombreux produits de consommation courante comme les cosmétiques, les produits alimentaires ou pharmaceutiques, les textiles, les produits d’entretien. En dépit de leur toxicité, ces molécules ne font l’objet d’aucun suivi réglementaire dans l’environnement. Aussi, ce travail porte sur la dynamique de ces micropolluants en milieu urbain : de leurs sources (à savoir les eaux grises et eaux vannes) jusqu’au milieu récepteur (amont-aval de l’agglomération parisienne par échantillonnage ponctuel et passif) en intégrant leur comportement en station d’épuration à l’échelle de l’ouvrage.Au niveau des sources, cinq types d’eau grise issus de douche, lavabo, lave-linge, lave-vaisselle et vaisselle manuelle ont été considérés. Une variabilité importante des concentrations au sein de chacune des eaux grises et entre les différents types d’eau grise a été observée. Cette variabilité est le reflet des pratiques de consommation des différents volontaires. Au final, les eaux des lave-linge et douche sont les plus contaminées. Pour les parabènes, le linge est la source majoritaire de contamination des eaux de lave-linge, dans le cas des eaux de douche, les personnes et les produits de soins corporels sont les principales sources de contamination.Depuis 2010, les flux quotidiens par habitant de ces molécules ont diminué significativement (d’un facteur compris entre 2 et 7 suivant la molécule). Cette diminution s’explique par (i) les changements de formulation des produits cosmétiques et (ii) l’apparition de nouvelles réglementations plus contraignantes.Le suivi du devenir en station d’épuration (sur Seine Centre), à l’échelle de l’ouvrage, a montré que le traitement primaire (décantation physico-chimique lamellaire) permet un abattement quasi-total du triclosan, les parabènes sont majoritairement éliminés lors de la biofiltration notamment au niveau du premier étage (Biofor). La généralisation d’un traitement tertiaire (du type Carboplus® suivi lors de ce travail) permettrait de réduire ces rejets.Les rejets urbains par temps de pluie (ici les déversoirs d’orage) constituent une source importante de contamination pour le milieu récepteur au regard des niveaux que nous avons observé. La combinaison des rejets des stations d’épuration, par temps sec et par temps de pluie, et des déversoirs d’orage contribue à augmenter les niveaux en parabènes, triclosan et triclocarban de la Seine comme le suivi de deux stations de mesure en amont et aval de l’agglomération parisienne l’a mis en évidence. Les échantillonneurs passifs sont des outils prometteurs pour déterminer la fraction biodisponible du TCS et du TCC. En effet, la méthode développée dans le cadre du projet Cosmet’eau a été appliquée avec succès à la Seine. / This Phd thesis is part of both the Cosmet’Eau project and the OPUR programme. It provides new insights into the dynamics of parabens, triclosan and triclocarban in urban areas under strong human pressure. These molecules are biocides commonly used as preservatives in a wide range of consumer products, such as cosmetics, food and pharmaceutical products, textiles and cleaning products. Despite their toxicity, these molecules are not subject to any regulatory monitoring in the environment. Also, this work deals with the dynamics of these micropollutants in urban areas: from their sources (namely gray water and sewage) to the receiving environment (upstream-downstream of the Parisian conurbation with punctual and passive sampling) along with their behavior at different stages of a wastewater treatment plant.At the source level, five types of greywater from shower, washbasin, washing machine, dishwasher and manual dish washing were considered. Significant variability in concentrations within each greywater and between different types of greywater was observed. This variability reflects the consumption practices of the different volunteers. Besides, the waters from washing machines and showers are the most contaminated. For parabens, clothes are the main source of contamination of washing machine waters, while in shower waters, people and personal care products are the main sources of contamination.Since 2010, per capita daily flows of these molecules have decreased significantly (by a factor between 2 and 7 depending on the molecule). This decrease can be explained by (i) changes in the formulation of cosmetic products and (ii) the emergence of new, more restrictive regulations. The monitoring of the fate in wastewater treatment plant (Seine Centre), at the scale of the device, showed that primary treatment (lamellar physico-chemical decantation) allows a quasi-total removal of triclosan, while parabens are predominantly eliminated during the biofiltration, at the level of the first stage (Biofor). The general use of a tertiary treatment (like Carboplus®, studied during this work) would reduce discharges to receiving waters of parabens, triclosan and triclocarban.Urban discharges during wet weather period (here combined sewer overfows) constitute a major source of contamination for the receiving waters with respect to the measured levels. The combination of sewage treatment plant discharges, during dry and wet weather periods, and combined sewer overfows contributes to increasing levels of parabens, triclosan and triclocarban in the Seine River, as the monitoring of two sites, upstream and downstream of the Paris conurbation, has highlighted it. Passive samplers are promising tools for determining the bioavailable fraction of TCS and TCC. Indeed, the method developed within the framework of the Cosmet'eau project has been successfully applied to the Seine
7

A study of the performance of biochar as adsorbing agent in o‐DGT devices / En studie av egenskaperna hos biokol som adsorberande agent i o‐DGT anordningar

Eliasson, Anna January 2017 (has links)
A new complex aspect in the matter of water quality is the occurrence of emerging organic pollutants and contaminants in waste water. The currently low extent to which treatment of waste water is performed in Brazil, and in the world as a whole, there is a considerable need for development of cheap and accurate in-situ sampling methods for far-reaching studies of surface water quality. The lack of such methods today makes the maintenance and establishing of sanitary safety difficult. This diploma work gives a brief introduction to the basic principles of the passive sampling method known as Diffusive Gradient in Thin-films (DGT). A method that could be useful for such monitoring of quality in water bodies world wide. The aim of this study is to develop a method, for the detection of organic emerging pollutants and contaminants – i.e. compounds, which usually are present at very low concentrations when found in the environment as a result of human activity. More specifically, this work investigates the potential and usefulness of the application of DGT devices in detection of organic compounds that can affect human health and ecosystems, even at low concentrations, however, their effects still are in need of further investigations. This study focuses on both purely technical as well as practical points of views. The efficiency of organic DGT (o-DGT) with biochar as the adsorbing agent is examined targeting the detection of organic pollutants and contaminants in surface water. In this sense, the specific aim of the work is to evaluate the performance of biochar as adsorbing agent. This work showed that the performance of biochar as the adsorbing agent in binding layers in o-DGT sample devices can be considered as satisfactory since all compounds of interest in this study was successfully detected, quantified an identified. Further investigations in the future are needed to determine the effects of varying pH, temperature and ion concentration in the deployment media, as well as the properties of the binding layer in relation to concentration of biochar and the thickness of the layer. These in order to optimize the method for in-situ water sampling, aiming conventional use of biochar as the adsorbing agent in the future.
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Aproveitamento do engaço da uva para remoção da cafeína por adsorção

Portinho, Rodrigo January 2016 (has links)
A preocupação com a presença de poluentes emergentes em meios hídricos vem crescendo, justificando a busca por técnicas alternativas ou adicionais às aplicadas nos processos convencionais de tratamento de água. A utilização da adsorção com resíduos agrícolas diretamente como adsorventes ou como precursores para síntese de carvão ativado apresenta-se como um método viável, aliando eficiência de remoção, baixo custo e biodegradabilidade do material aplicado. O presente trabalho objetivou estudar a empregabilidade do engaço da uva, um resíduo do processo de industrialização da uva sem aplicação prática efetiva, na remoção de cafeína de solução aquosa. Este poluente emergente foi selecionado por ser amplamente encontrado em águas superficiais, subterrâneas e até mesmo potáveis, além de ser a substância alteradora de comportamento mais consumida mundialmente. O engaço foi utilizado como adsorvente em formas distintas: bruto com apenas ajuste da granulometria (ENG), modificado através da ação do ácido fosfórico (ENGI) e na forma de carvões ativados (CAE50%, CAE70% e CAE85%). No caso do ENG e ENGI foi estudada a variação dos parâmetros pH, tempo de residência e concentração de sólido adsorvente, de forma a encontrar as condições ideais para os processos em batelada. Para o carvão ativado que apresentou melhores resultados (CAE85%), por outro lado, os percentuais de remoção de cafeína foram elevados, mesmo para a menor quantidade de adsorvente possível de ser medida com precisão aceitável, não justificando a variação do parâmetro de concentração. Foram observados maiores índices de remoção em soluções ácidas, com os valores de pH considerados ideais de 2,0 para ENG e ENGI e 4,0 para o CAE85%. Os tempos de residência e concentrações de sólidos adsorventes ideais foram de 40 min e 25 g L-1 (ENG), 30 min e 15 g L-1 (ENGI) e 30 min (CAE85%). Ademais, o equilíbrio foi avaliado a partir da construção das isotermas de adsorção, as quais foram mais bem representadas pelo modelo de Sips, exibindo coeficientes de determinação R² iguais a 0,994, 0,999 e 0,987 e capacidades máximas de adsorção qmáx iguais a 89,2, 129,6 e 916,7 mg g-1. Características particulares dos sólidos adsorventes como áreas específicas superficiais e volumes de microporos também foram determinadas, resultando para o ENG, ENGI e CAE85% em 6,23, 4,21 e 1099,86 m² g-1 e 0,003, 0,002 e 0,568 cm³ g-1, respectivamente. / Concern over emerging pollutants presence in water resources is growing, justifying the search for alternative or additional techniques to those applied in conventional water treatment processes. Use of adsorption with agricultural wastes directly as adsorbents or as precursors for activated carbon synthesis is a viable method, combining removal efficiency, low cost and biodegradability of the material applied. This study investigated the employability of grape stalk, a waste from grape industrialization process without effective use, in caffeine removal from aqueous solution. This emerging pollutant was selected because it is widely found in surface water, groundwater and even drinking water, besides being the most consumed behaviorally active substance. Grape stalk was used in different forms: raw with only grain size adjustment (ENG), modified by phosphoric acid action (ENGI) and as activated carbons (CAE50%, CAE70% and CAE85%). In the case of ENG and ENGI, parameters pH, retention time and adsorbent concentration were varied in order to find the ideal batch process conditions. For the activated carbon that presented better results (CAE85%), on the other hand, caffeine removal percentages were high even for the least amount of adsorbent that could be measured with acceptable accuracy, which did not justify variation of the concentration parameter. Better removal percentages were observed in acid solutions, with ideal pH values being considered as 2.0 for ENG and ENGI and 4.0 for CAE85%. Ideal residence time and adsorbent concentration were 40 min and 25 g L-1 (ENG), 30 min and 15 g L-1 (ENGI) and 30 min (CAE85%). Moreover, equilibrium was evaluated through adsorption isotherms construction, which were best represent by Sips model, displaying determination coefficient R² equal to 0.994, 0.999 and 0.987 and maximum adsorption capacities equal to 89.2, 129.6 and 916.7 mg g-1. Adsorbents particular characteristics such as specific surface areas and micropore volumes were also determined, resulting in 6.23, 4.21 and 1099.86 m² g-1 and 0.003, 0.002 and 0.568 cm³ g-1 for ENG, ENGI and CAE85%, respectively.
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Estudo sobre a ocorrência de poluentes emergentes na água do rio meia ponte na cidade de Goiânia- Go / Study of the occurrence of emerging pollutants in meia ponte river's water in Goiânia - Go

Fonseca, Yara Vanessa Portuguez 27 August 2013 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2014-09-30T17:52:25Z No. of bitstreams: 2 YARA VANESSA PORTUGUEZ FONSECA_ MARIANGELA FONTES SANTIAGO_ESTUDO SOBRE A OCORRÊNCIA DE POLUENTES EMERGENTES NA ÁGUA DO RI.pdf: 4799034 bytes, checksum: e87c5460f5118c81795e4d5e3a1b5884 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-09-30T18:17:45Z (GMT) No. of bitstreams: 2 YARA VANESSA PORTUGUEZ FONSECA_ MARIANGELA FONTES SANTIAGO_ESTUDO SOBRE A OCORRÊNCIA DE POLUENTES EMERGENTES NA ÁGUA DO RI.pdf: 4799034 bytes, checksum: e87c5460f5118c81795e4d5e3a1b5884 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-30T18:17:45Z (GMT). No. of bitstreams: 2 YARA VANESSA PORTUGUEZ FONSECA_ MARIANGELA FONTES SANTIAGO_ESTUDO SOBRE A OCORRÊNCIA DE POLUENTES EMERGENTES NA ÁGUA DO RI.pdf: 4799034 bytes, checksum: e87c5460f5118c81795e4d5e3a1b5884 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-08-27 / Several studies indicates the presence of emerging pollutants in surface water, these substances not covered by the legislation came from untreated effluent discharges The present study aimed to evaluate the occurrence of anthropogenic marker caffeine and emerging pollutants Triclosan, β-blockers (atenolol and propranolol), analgesics (ibuprofen, naproxen, diclofenac, carbamazepine) and hormones (estrone, 17-β-estradiol, 17α-ethinylestradiol , cyproterone acetate, gestodene and levonorgestrel) in water Meia Ponte River in the city of Goiânia-GO. By High Performance Liquid Chromatography - HPLC and fast Ultra High Performance Liquid Chromatography - UHPLC. Physical, chemical and microbiological parameters (turbidity, temperature, pH, Phosphorus, Total Solids, Filterable Solids, Total Coliforms, E. Coli, COD, conductivity, nitrate, DO, BOD) were analyzed to assess the changes of these characteristics during sampling. There were two sampling campaigns in one rainy season and another in the dry season. Samples were collected at six points in the watercourse Meia Ponte, within the boundaries of the Goiânia. The samples were analyzed by UHPLC at LBGQA (UFScar).The compounds analysed were caffeine, ibuprofen, naproxen, diclofenac, carbamazepine, atenolol, propranolol, triclosan, estrone, 17-β-estradiol, 17αethinylestradiol. The physical, chemical and microbiological and Water-Quality Index -WQI indicated that the same river at the point where this capture held in poor condition with evidence of contamination by sewage. Nine Of the eleven emerging pollutants studied were detected at concentrations between 0.61- ng. L-1 22 ng. L-1. The highest concentrations were found in point 3, after the release of STP(Sewage Treatment Plant) Hélio Seixo de Brito in the dry season and the lowest in point 1 where it is held to capture WTP (Water Treatment Plant) Eng Rodolfo José da Costa e Silva, in the rainy season. Caffeine (rainy season 17,91 – 12746,18 ng. L-1 dry season 20,52 – 22917,10 ng. L-1), triclosan (rainy season 2,68 – 6,01 ng. L-1 dry season 5,17 – 82,43,10 ng. L-1) and β-blockers (rainy season 0,61 – 475,76 ng. L-1 dry season 1,46 – 961,08 ng. L-1)were identified with 100% frequency, analgesics (rainy season 7,35 – 120,03 ng. L-1 dry season 4,17 – 404,71ng. L-1) had an average frequency of 70% and from the hormones analyzed, only estrone (<LOQ - 8.60 ng. L -1) was detected in the points after the STP Hélio Seixo Brito in the dry season. The load calculation in this study showed that the behavior of the load did not follow the concentration at all times for all compounds. Some compounds had greater input in the rainy season even when its highest concentration was found in the dry season and others maintained high loads independent of the flow. A PCA was calculated correlating emerging pollutants detected and physical parameters, chemical and microbiological. And was identified a correlation between collection points and also between the variables. / Diversos estudos indicam a presença de poluentes emergentes em água superficial essas substâncias não contempladas pela legislação são provenientes de lançamentos de efluentes com pouco ou nenhum tratamento. O presente estudo objetivou avaliar a ocorrência do marcador antrópico Cafeína e dos poluentes emergentes Triclosan, β-Bloqueadores (atenolol e propranolol), Analgésicos (ibuprofeno, naproxeno, diclofenaco, carbamazepina) e Hormônios (estrona, 17-β-estradiol, 17α-etinilestradiol, Acetato de ciproterona, Gestodeno e Levonorgestrel) na água do rio Meia Ponte na cidade de Goiânia-GO. Por meio da Cromatografia Líquida de Alta Eficiência – HPLC e Ultra rápida Cromatografia Líquida de Alta Eficiência – UHPLC. Parâmetros físicos, químicos e microbiológicos (Turbidez, Temperatura, pH, Fósforo, Sólidos Totais, Sólidos Filtráveis, Coliformes totais, E. Coli, DQO, Condutividade, Nitrato, OD, DBO) foram analisados para avaliar as alterações dessas características no momento da coleta. Foram realizadas duas campanhas amostrais uma no período chuvoso e outro no período de estiagem. As amostras foram coletadas em seis pontos no curso d’água Meia Ponte, dentro do perímetro do município de Goiânia. As amostras foram analisadas por meio do UHPLC do LBGqA da UFScar e os compostos cafeína, ibuprofeno, naproxeno, diclofenaco, carbamazepina, atenolol, propanolol, triclosan, estrona, 17-β-estradiol, 17α-etinilestradiol foram analisados. Os parâmetros físicos, químicos e microbiológico e o Índice de Qualidade Água- IQA indicaram que o rio mesmo no ponto onde realizada captação esta numa condição ruim com indícios de contaminação por esgoto. Dos onze poluentes emergentes estudados nove foram detectados com concentrações entre 0,61 ng. L-1 a 22µg.l-1. As maiores concentrações foram verificadas no ponto 3, após o lançamento da Estação de Tratamento de Esgoto- ETE Hélio Seixo de Brito no período de estiagem e as Engº Rodolfo José da Costa e Silva, no período de cheia. A cafeína (Cheia 17,91 – 12746,18 ng. L-1 estiagem 20,52 – 22917,10 ng. L-1), o triclosan (Cheia 2,68 – 6,01 ng. L-1 estiagem 5,17 – 82,43 ng. L-1) e os β-Bloqueadores (Cheia 0,61 – 475,76 ng. L-1 estiagem 1,46 – 961,08 ng. L-1), foram identificados com 100% de frequência, os analgésicos (Cheia 7,35 – 120,03 ng. L-1 estiagem 4,17 – 404,71 ng. L-1) tiveram em media 70% de frequência e dos hormônios analisados apenas a estrona (<LQ - 8,60 ng. L-1) foi detectada nos pontos após a ETE Hélio Seixo de Brito no período de estiagem. O cálculo das cargas neste estudo mostrou que o comportamento da carga não acompanhou o da concentração em todos os momentos para todos os compostos. Alguns compostos tinham maior presença na estação chuvosa mesmo quando sua maior concentração foi identificada no período de estiagem e outros mantiveram altas cargas independente da vazão do manancial. Foi calculado um PCA (análise de componentes principais) correlacionando os poluentes emergentes detectados e os parâmetros físico, químicos e microbiológicos e foi identificada uma correlação entre pontos de coleta e também entre as variáveis. menores no ponto 1 onde é realizada a captação da Estação de Tratamento de Água- ETA
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Estudo da degradação da enrofloxacina em solução aquosa por meio de processos foto-oxidativos. / Study of degradation of enrofloration solution through process photo-oxidative.

Dias, Meriellen 19 April 2013 (has links)
As tecnologias utilizadas em estações de tratamento de água e efluentes não são eficientes para a remoção total de resíduos farmacêuticos e os efeitos dessas substâncias sobre o meio ambiente e a saúde humana ainda não são bem conhecidos. No presente trabalho, estudou-se a degradação do antibiótico enrofloxacina (ENRO) por fotólise e pelo processo H2O2/UV na presença de compostos bio-orgânicos (BOS), que têm se apresentado como interessantes promotores da oxidação de poluentes. Os experimentos foram realizados em um reator fotoquímico tubular de imersão com fonte radiante (lâmpada de xenônio) concêntrica, operado em batelada com recirculação. Utilizaram-se concentrações iniciais de ENRO e de BOS iguais a 50 mg L-1 e 20 mg L-1, respectivamente. Para todos os pH mantidos constantes (3, 5, 7 ou 9), a solução foi irradiada por 240 minutos. Os resultados indicam que o antibiótico não sofreu hidrólise em qualquer dos pH estudados em um período de 24 horas. Por sua vez, a fotólise da enrofloxacina mostrou-se eficiente somente na presença do composto bioorgânico CVT 230 (BOS C), com remoção de ENRO de quase 90% em meio neutro (pH 7). Resultados da literatura, associados a experimento realizado em meio anóxico, sugerem a participação de oxigênio singlete como principal espécie oxidante da enrofloxacina. Por outro lado, a degradação da ENRO pelo processo H2O2/UV apresentou remoção máxima do fármaco de 48% em pH 7, o que sugere que a ação de oxigênio singlete e/ou radicais hidroxila não foi eficaz na presença de peróxido de hidrogênio. Portanto, o BOS C pode ser empregado como promotor no tratamento de águas e efluentes aquosos contaminados com enrofloxacina sob baixas potências radiantes ou em sistemas irradiados por luz solar. / The technologies used in water and wastewater treatment plants are not efficient for the total removal of pharmaceutical compounds whose effect to the environment and to human health are still not well known. In this work, the degradation of the antibiotic enrofloxacin (ENRO) was studied by photolysis and by the H2O2/UV process in the presence of bio-organic substances (BOS), which have been identified as interesting promoters of pollutant oxidation. The experiments were carried out in a tubular immersion photochemical reactor equipped with a concentric radiant source (xenon lamp), and operated in batch mode with recirculation. Initial ENRO and BOS concentrations of 50 mg L-1 and 20 mg L-1 were used, respectively. The solution was irradiated for 240 minutes for all pH studied at constant values (3, 5, 7, and 9). The results show that the antibiotic did not undergo hydrolysis at any pH after 24 hours. The photolysis of enrofloxacin showed to be efficient only in the presence of the bio-organic substance CVT 230 (BOS C), with almost 90% ENRO removal in neutral solution (pH 7). Results from the literature, associated with an experiment carried out in anoxic conditions, suggest singlet oxygen as the main species responsible for enrofloxacin oxidation. On the other hand, ENRO degradation by the H2O2/UV process showed a maximum removal of 48% at pH 7, suggesting that the action of singlet oxygen and/or hydroxyl radicals was not effective in the presence of hydrogen peroxide. BOS C can therefore be used as an efficient promoter for the treatment of enrofloxacin-containing water and wastewater under low irradiant power or in solar-irradiated systems.

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