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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.
81

Analytical determination of emerging contaminants by using a new graphene-based enrichment material for solid-phase extraction and passive sampling

Liu, Yang 24 March 2020 (has links)
Emerging contaminants represent newly identified organic chemical pollutants that are not yet covered by routine monitoring and regulatory programs. Current research on these contaminants is greatly hindered by the shortage of analytical methods due to the complex matrices, extremely low concentration and their “emerging” nature. In this study the innovative analytical and monitoring methods have been developed and validated for determination of emerging pollutants in water (including pharmaceutical and personal care products, pesticides and artificial sweeteners) based on graphene-silica composite as the solid-phase extraction (SPE) sorbent and as the receiving phase in passive sampler. Graphene, a new allotropic member in the carbon family, has been considered to be a promising candidate for sorption material with high loading capacity because of its ultra-high specific surface area and large delocalized π-electron-rich structure. The composite employed in this work was synthesized by using the cross-link agent to covalently combine carboxylic acid groups of graphene-oxide with the amino groups of the modified silica gel. Afterwards, graphene-silica composite was obtained after treated with hydrothermal reaction in the microwave autoclave, which was demonstrated by X-ray diffraction (XRD). The analytical procedure entails SPE followed by high performance liquid chromatography equipped with tandem mass spectrometers (HPLC-MS/MS). Several crucial parameters were optimized to improve recovery of the analytes, including the amount of sorbents, the ratio of graphene oxide/amino-silica and pH value of water samples. The best recovery results were achieved with 100 mg 10 % (w/w) graphene-silica composite, which were over 70 % except four artificial sweeteners, ranitidine and triclosan. Compared with its commercial counterpart Oasis HLB, pH value variation of water samples has less effect on the recoveries, making graphene composite to be a potential receiving phase of monitoring tool. The batch-to-batch reproducibility was verified on six independently SPE cartridges with graphene-silica composites from two repeatable synthetic batches, showing relative standard deviations (RSDs) in the range of 8.3 % to 19.1 %, except ibuprofen and saccharin. The cartridges proved to be reusable for at least 10 times consecutive extractions, with RSD < 14.9 %, except ibuprofen and diclofenac. The Chemcatcher® passive sampler is frequently used for monitoring polar organic chemicals in surface water. Uptake kinetics is necessary to be quantified to calculate time-weighted average (TWA) concentration. A series of calibration experiments were conducted in the beaker renewal experiments as well as in the flow-through system with styrenedivinylbenzene-cross connect (SDB-XC) disks and graphene-silica composite as the receiving phase. The results obtained from the beaker renewal experiments showed that the uptake kinetics of accumulated compounds with all Chemcatcher® configurations can keep linear within 2 weeks. The innovative configuration using graphene-silica composite powder placed between two PES membranes was able to accumulate eleven of the selected compounds with uptake rate (Rs) from 0.01 L/day (acesulfame K and sucralose) to 0.08 L/day (chlothianidin), while its commercial counterpart SDB-XC disks with polyethersulfone (PES) membranes can accumulate seven substances with Rs from 0.02 L/day (sucralose and chlothianidin) to 0.15 L/day (carbamazepine). In the flow-through system, when Chemcatchers® were equipped with SDB-XC disks without PES membranes, the linear uptake range for the majority of compounds was only in one week, except atrazine. The Rs of accumulated compounds were from 0.16 L/day (chloramphenicol) to 1.04 L/day (metoprolol) that are higher than the same substances in the beaker renewal experiments, in which the Rs of chloramphenicol and metoprolol were 0.09 L/day and 0.56 L/day respectively. However, if the PES membranes were employed, the uptake kinetics in both calibration experimental designs were comparable: the Rs of accumulated compounds from the configuration with SDB-XC disks covered by PES membranes were from 0.035 L/day (sucralose) to 0.17 L/day (carbamazepine) and from the configuration with graphene-silica composite were from 0.01 L/day (gemfibrozil) to 0.08 L/day (chlothianidin). Moreover, the uptake range can keep linear within two weeks. The developed Chemcatcher® method was successfully applied in real surface waters. 1-H benzontriazole, tolyltriazole and caffeine were the main contaminants in Elbe River and the Saidenbach drinking water reservoir. The investigated results between summer and autumn monitoring period were not significantly different.:Acknowledgement I Abstract III Zusammenfassung V Content IX List of Figures XIII List of Tables XVII Table of Abbreviations XIX 1. Motivation 1 2. Introduction 3 2.1 Emerging contaminants 3 2.1.1 Definition 3 2.1.2 Sources 3 2.1.3 Concern about the adverse impacts 5 2.2 Analysis of the emerging contaminants 7 2.2.1 General analytical process 7 2.2.2 Enrichment techniques 8 2.2.2.1 Liquid-liquid extraction (LLE) 8 2.2.2.2 Solid-phase extraction (SPE) 9 2.2.2.3 Innovative type of solid-phase extraction 13 2.2.3 Analytical methods 15 2.3 Graphene and its application in analytical chemistry 19 2.3.1 Introduction 19 2.3.2 Synthesis methods of graphene 20 2.3.3 Application in sample pre-treatment 21 2.3.3.1 Graphene-based material as SPE sorbent 21 2.3.3.2 Graphene-coated fibers as SPME sorbent 22 2.3.3.3 Magnetic graphene as MSPE sorbent 23 2.3.3.4 Graphene-based MIPs 24 2.4 Chemcatcher®—a passive sampling technique 25 2.4.1 Introduction 25 2.4.2 Theory 26 2.4.2.1 Equilibrium passive sampling 27 2.4.2.2 Kinetic passive sampling 28 2.4.3 Concept of Chemcatcher® 28 2.4.4 Calibration of Chemcatcher® 33 2.4.5 Performance and reference compounds 36 3. Study objectives and hypotheses 39 3.1 Study objectives 39 3.2 Hypotheses 41 4. Material and methods 43 4.1 Materials 43 4.1.1 Chemicals and solutions 43 4.1.2 Consumable materials and instruments 44 4.2 Synthesis of graphene-silica composite 46 4.3 SPE experiments 49 4.3.1 Packing method 49 4.3.2 SPE procedure 49 4.3.3 Optimization of SPE procedures 51 4.3.4 Repeatability and reusability test 52 4.4 Chemcatcher® experiments 53 4.4.1 Preparation and precondition 53 4.4.2 Calibration of Chemcatcher® 55 4.4.2.1 Preliminary test 55 4.4.2.2 Experimental design of the beaker batch tests 56 4.4.2.3 Experimental design of the flow-through system 57 4.4.3 Monitoring application of Chemcatcher® in surface water 59 4.4.4 Elution process 60 4.4.5 Statistic data evaluation 61 4.5 HPLC-MS/MS analysis 62 5. Results and discussion 63 5.1 Preparation and characterization of graphene-silica composite 63 5.2 SPE performance of the graphene-silica composite 67 5.2.1 Preliminary test of packing methods 67 5.2.2 Optimization of SPE procedures 68 5.2.2.1 The amount of sorbent 68 5.2.2.2 Graphene ratio in the composites 68 5.2.2.3 pH value of the water sample 69 5.2.3 Repeatability and reusability test 72 5.2.3.1 Performance of the off-line SPE 72 5.2.3.2 Repeatability and reusability test results 75 5.2.4 Summarized discussion of the SPE performance 76 5.3 Calibrating results of Chemcatcher® 86 5.3.1 Pre-test results 86 5.3.1.1 Feasibility test of commercial disks as receiving phase 86 5.3.1.2 Stability test 88 5.3.1.3 Elution optimization. 88 5.3.1.4 Recovery of the filters 92 5.3.2 Calibration results of renewal experiments 93 5.3.2.1 SDB-XC disks without and with membranes 93 5.3.2.2 Graphene-silica composite as receiving phase 97 5.3.3 Calibration results of the flow-through system experiments 101 5.3.3.1 Determination of experimental parameters 101 5.3.3.2 Concentration control 103 5.3.3.3 Calibration results 105 5.3.3.4 Preliminary evaluation of performance and reference compounds 112 5.4 Application of Chemcatcher® in surface water 114 5.5 Discussion about problems of commercial disks as receiving phase in Chemcatcher® 118 5.5.1 Deformation of commercial disks 118 5.5.2 The particles in the solution after elution 119 6. Conclusion and perspective 121 7. Annex 125 7.1 Material and methods 125 7.1.1 Chemicals 125 7.1.2 Silica gel and graphene oxide 144 7.1.3 Microwave reduction program 144 7.1.4 Working schedule of the calibration experiments in flow-through system 144 7.1.5 HPLC-MS/MS conditions 146 7.2 Experimental results 149 7.2.1 Stability of the colloid solution of graphene oxide 149 7.2.2 EDX analysis results 149 7.2.3 HPLC-MS/MS results 152 7.2.4 Calibrating results of the beaker renewal experiment 153 7.2.5 Calibrating results of the flow-through system experiments 157 7.2.6 Monitoring results in the Elbe River 161 Reference 163
82

Développement d’une méthode d’extraction des contaminants émergents dans les solides particulaires par LDTD-APCI-MS/MS

Darwano, Hicham 11 1900 (has links)
Douze contaminants émergents (composés pharmaceutiques, pesticides et hormones) ont été quantifiés et extraits de l'eau de rivières et d’échantillons d'eaux usées municipales. La séparation des solides en suspension est effectuée par filtration des échantillons d'eau. L'effet de filtration sur les concentrations de contaminants dissous a été évaluée afin de minimiser les pertes de composés cibles. Les échantillons ont été lyophilisés et ont été extraits en deux cycles par ultrasons combinés avec une étape de nettoyage sur cartouche d’extraction de type C18. La quantification a été réalisée en utilisant la spectrométrie de masse. Les recouvrements de la méthode pour tous les composés ont varié de 68 à 112% dans toutes les matrices étudiées, sauf pour le sulfaméthoxazole et le diclofénac où des recouvrements plus modestes ont été obtenus (38 à 85%). Les limites de détection pour les 12 analytes dans les sédiments et particules en suspension (SPM) de la rivière variaient de 0,7 à 9,4 ng g-1 et de 21 à 92 ng g-1, pour les échantillons SPM de station d'épuration. Tous les contaminants émergents cibles ont été détectés à des concentrations variant de 3 à 5440 ng g-1 dans les matrices étudiées, les concentrations les plus élevées ont été observées dans les échantillons SPM de stations d'épuration. Une partie importante de certains de ces contaminants est clairement associée aux sédiments de rivière ou aux particules en suspension. L’optimisation des processus de traitement de l'eau et le devenir environnemental doit absolument tenir compte de la fraction de contaminants qui liée à des particules si on espère avoir un bilan de masse raisonnable. / We developed a protocol to quantify 12 emerging contaminants (pharmaceuticals and hormones) and pesticides extracted from suspended particulate matter (SPM) of river water and municipal wastewaters samples. The separation of suspended solids was carried through filtration of water samples. We tested a series of 6 different filter types. The effect of filtration on the concentrations of dissolved contaminants was evaluated in order to minimize losses of target compounds. The river bottom sediments samples were lyophilized and both SPM and sediment samples were subjected to ultrasonic extraction combined with C18 cartridge clean-up. Quantifications were realized using mass spectrometry. The overall method recoveries of all compounds ranged from 38 to 112 % in all studied matrices, poor recoveries were achieved for sulfamethoxazole and diclofenac (recoveries for all other compounds in the wastewater treatment plant (WWTP) samples were 68 to 111%). The detection limits in sediments and SPM from river samples for the 12 analytes varied from 0.7 to 9.4 ng g-1 and from 21 to 92 ng g-1 for WWTP SPM samples. All target emerging contaminants were detected with concentrations ranging from 3 to 5440 ng g-1 in the studied matrices, with the highest concentrations observed in WWTP SPM samples. A significant portion of some of those contaminants is clearly associated with bottom sediments or suspended particulates. Optimization of water treatment processes and environmental fate must absolutely consider the fraction of contaminants which is particulate-bound if one hopes to have a reasonable mass balance.
83

Dégradation chimique et biologique de neuf contaminants émergents dans les eaux de surfaces et les effluents primaires d’eaux usées municipales

Cormier, Guillaume 04 1900 (has links)
Un protocole inspiré du test de simulation 309 de l’Organisation de coopération et de développement économiques (OCDE) nous a permis de mesurer la dégradation chimique (excluant la photolyse) dans des eaux de surface de même que la dégradation chimique et biologique de neuf contaminants émergents dans l’effluent d’un décanteur primaire d’eau usée municipale. Les données étaient compatibles avec le modèle de cinétique de pseudo ordre un. Les résultats démontrant une persistance de plus d’un an dans les eaux de surface et de 71 jours dans l’effluent du décanteur primaire suggèrent que les dégradations chimique et biologique ne contribuent pas significativement à la diminution de: atrazine, déséthylatrazine, carbamazépine et diclofénac dans la phase aqueuse des systèmes testés. Les autres composés se sont dégradés à différents niveaux. Le 17ß-estradiol ainsi que l’éthinylestradiol, la noréthindrone, la caféine et le sulfaméthoxazole ont tous été sujet à la dégradation biologique dans les effluents du décanteur primaire d’eau usée avec des constantes de dégradation k et des demi-vies t1/2 mesurées allant respectivement de 0.0082 à 0.59 j-1 et de 1.2 à 85 jours. Les paramètres de cinétique mesurés peuvent être combinés aux concentrations typiques des composés à l’étude dans un décanteur primaire d’eau usée pour y calculer leur vitesse de dégradation. Cependant, puisque les décanteurs primaires dans les usines de traitement d’eaux usées ont généralement des temps de résidence de quelques heures seulement, il est improbable que les neufs contaminants émergents à l’étude diminuent significativement par ces processus durant leur passage dans le compartiment. / A protocol inspired by the OECD 309 simulation test allowed us to measure the chemical (excluding photolysis) degradation in surface waters as well as the chemical and biological degradation potential of 9 emerging contaminants in urban primary settling tank (PST) effluents. The data confirmed that a pseudo first order kinetic model provided a good fit. The results suggest that chemical and biological degradation will not significantly contribute to the disappearance of atrazine, desethylatrazine, carbamazepine and sulfamethoxazole in the aqueous phase of the tested systems given the reported persistency of more than a year in surface waters and 71 days in PST effluents. Other compounds were more easily degraded and 17ß-estradiol, ethinylestradiol, norethindrone, caffeine and sulfamethoxazole were all amenable to biological degradation in PST effluents, with measured degradation rate constants k and half-lives ranging respectively from 0.0082-0.59 d-1 and 1.2-85 days. Since PSTs in WWTPs generally have a water residence time of a few hours and considering the typical concentrations of such ECs’ in those compartments, it is unlikely that significant disappearance will occur during their passage through the PST.
84

Développement d’une méthode multi-résidu pour l’analyse de contaminants émergents dans des échantillons solides et liquides à partir de la spectrométrie de masse à haute résolution

Comtois-Marotte, Simon 04 1900 (has links)
L’analyse des contaminants émergents (ECs) suscite l’intérêt de la communauté scientifique, de sorte que plusieurs études ont rapporté leur présence dans les eaux usées et dans les eaux de surface. Toutefois, la plupart des études ont concentré leurs travaux principalement sur la phase dissoute, si bien que la concentration des ECSs dans les particules en suspension (SPM – suspended particulate matter) demeure peu connue. De plus, la plupart des méthodes traitant l’analyse des ECs sont basées sur le couplage de la chromatographie liquide couplée à un triple quadripôle (QqQ). Typiquement, ces QqQ fonctionnent à basse résolution, augmentant ainsi la probabilité d’obtenir des faux positifs. Afin de diminuer le taux de faux positifs un nouveau protocole permettant l’analyse de 31 ECs dans la fraction dissoute et la fraction solide a été développé à l’aide de la spectrométrie de masse à haute résolution. De plus, un dépistage du potentiel estrogénique par des levures a été effectué. Cela représente l’un des premiers rapports décrivant les concentrations en ECs dans les eaux usées et les SPM combiné avec un dépistage du potentiel estrogénique. La séparation des particules en suspension a été réalisée via la filtration des échantillons liquides. Les ECs ont été extraits de la fraction solide à l’aide d’ultrasons en utilisant du MeOH : ACN (1:1, v/v) avec l’ajout de 1% de HCOOH. Par la suite, l’extrait de la fraction solide et de la phase aqueuse ont été soumis à la SPE (solid phase extraction – extraction sur phase solide) à l’aide d’une cartouche polymérique composé d’acide benzènesulfonique. Une colonne de type C-18 a été utilisée pour séparer les ECs sélectionnés. Un spectromètre de masse de haute résolution (Q-Exactive), constitué d’un quadripôle et d’une trappe ionique orbitale à haute résolution a été utilisé en mode balayage (FS, full scan) avec une résolution de 70 000 FWHM (FWHM– Largeur à mi-hauteur, Full width at half maximum) à m/z 200 pour l’analyse de la fraction solide et en mode suivi des réactions parallèles (PRM, Parallel reaction monitoring) à 17 500 FWHM à m/z 200 pour la fraction liquide. Une ionisation chimique à pression atmosphérique (APCI, Atmospheric pressure chemical ionisation) en modes positif et négatif a été utilisée. La méthode a été appliquée sur des échantillons réels afin de déterminer non seulement la portion d’ECs sur les SPM, mais également leur devenir dans le traitement des eaux usées jusqu’à leur déversement dans les eaux réceptrices. La récupération des composés d’intérêt a été de 27 à 102 % et de 43 à 122%, pour la fraction solide et liquide respectivement. Les limites de détections se situaient entre 0.5 à 104 ng L-1 et de 0.3 à 2.3 ng g-1. Les courbes d’étalonnages dans les matrices d’eaux usées et les solides ont montré une bonne linéarité (R2 > 0.991) pour les analytes cibles ainsi qu’une précision acceptable avec des coefficients de variation inférieurs à 25%. / The trace analysis of emerging contaminants (ECs) is gaining more interest and several studies have widely reported their occurrence in waste and surface water. However, most studies found in the literature reported concentrations only in the dissolved phase often without considering the suspended particulate matter (SPM). Moreover, most of the methods dealing with the analysis of ECs are based on liquid chromatography tandem mass spectrometry with a triple quadruple (QqQ). The majority of QqQ operate at low resolution, thus increasing the possibility of false positive identification. The current study presents a new protocol to quantify 31 emerging contaminants not only in the effluent wastewater, but also from SPM of municipal wastewater samples using high-resolution mass spectrometry, an improvement to reduce false positives. Furthermore, Yeast estrogen screen assay (YES-assay) adapted from direct measurement of estrogenic activity was tested on filtered wastewater samples. This represents one of the first reports describing ECs in wastewater and SPM with direct measurement of estrogenic activity. The separation of suspended particulate matter was realized using filtered water samples. The ECs were extracted from the matrix by sonication using MeOH:ACN (1:1, v/v) with 1% HCOOH. Thereafter, the extracts of the solid fraction and the aqueous phase were subjected to an off-line solid phase extraction (SPE) with a Strata-X-C cartridge to concentrate and clean-up the extracts. A C18 chromatography column was used to separate ECs. A QExactive mass spectrometer, which combines a quadruple analyser with a high resolution orbital ion trap (OrbitrapTM) was used in full scan (FS) mode with 70 000 FWHM (Full width at half maximum) at m/z 200 for analysis of the solid fraction, while analysis of the liquid fraction was realised using parallel reaction monitoring (PRM) with 17 500 FWHM at m/z 200. An APCI (Atmospheric Pressure Chemical Ionization) source in positive and negative mode was used for the ionization of target compounds. The method was successfully applied to real samples allowing us to determine the proportion of ECs in suspended particulate and the fate of the selected ECs during wastewater-treatment processes and their release into receiving surface waters. Recoveries of target compounds ranged from 27 to 102 % and from 43 to 122 % for the liquid and the solid fraction respectively. The limits of detection ranged from 0.5 to 104 ng L-1 and from 0.3 to 2.3 ng g-1. Calibration curves in wastewater and solid matrix showed good linearity (R2 > 0.991), for all target analytes, and precision (intraday and interday) showed coefficients of variation below 25%.
85

Développement d’une méthode d’extraction des contaminants émergents dans les solides particulaires par LDTD-APCI-MS/MS

Darwano, Hicham 11 1900 (has links)
Douze contaminants émergents (composés pharmaceutiques, pesticides et hormones) ont été quantifiés et extraits de l'eau de rivières et d’échantillons d'eaux usées municipales. La séparation des solides en suspension est effectuée par filtration des échantillons d'eau. L'effet de filtration sur les concentrations de contaminants dissous a été évaluée afin de minimiser les pertes de composés cibles. Les échantillons ont été lyophilisés et ont été extraits en deux cycles par ultrasons combinés avec une étape de nettoyage sur cartouche d’extraction de type C18. La quantification a été réalisée en utilisant la spectrométrie de masse. Les recouvrements de la méthode pour tous les composés ont varié de 68 à 112% dans toutes les matrices étudiées, sauf pour le sulfaméthoxazole et le diclofénac où des recouvrements plus modestes ont été obtenus (38 à 85%). Les limites de détection pour les 12 analytes dans les sédiments et particules en suspension (SPM) de la rivière variaient de 0,7 à 9,4 ng g-1 et de 21 à 92 ng g-1, pour les échantillons SPM de station d'épuration. Tous les contaminants émergents cibles ont été détectés à des concentrations variant de 3 à 5440 ng g-1 dans les matrices étudiées, les concentrations les plus élevées ont été observées dans les échantillons SPM de stations d'épuration. Une partie importante de certains de ces contaminants est clairement associée aux sédiments de rivière ou aux particules en suspension. L’optimisation des processus de traitement de l'eau et le devenir environnemental doit absolument tenir compte de la fraction de contaminants qui liée à des particules si on espère avoir un bilan de masse raisonnable. / We developed a protocol to quantify 12 emerging contaminants (pharmaceuticals and hormones) and pesticides extracted from suspended particulate matter (SPM) of river water and municipal wastewaters samples. The separation of suspended solids was carried through filtration of water samples. We tested a series of 6 different filter types. The effect of filtration on the concentrations of dissolved contaminants was evaluated in order to minimize losses of target compounds. The river bottom sediments samples were lyophilized and both SPM and sediment samples were subjected to ultrasonic extraction combined with C18 cartridge clean-up. Quantifications were realized using mass spectrometry. The overall method recoveries of all compounds ranged from 38 to 112 % in all studied matrices, poor recoveries were achieved for sulfamethoxazole and diclofenac (recoveries for all other compounds in the wastewater treatment plant (WWTP) samples were 68 to 111%). The detection limits in sediments and SPM from river samples for the 12 analytes varied from 0.7 to 9.4 ng g-1 and from 21 to 92 ng g-1 for WWTP SPM samples. All target emerging contaminants were detected with concentrations ranging from 3 to 5440 ng g-1 in the studied matrices, with the highest concentrations observed in WWTP SPM samples. A significant portion of some of those contaminants is clearly associated with bottom sediments or suspended particulates. Optimization of water treatment processes and environmental fate must absolutely consider the fraction of contaminants which is particulate-bound if one hopes to have a reasonable mass balance.
86

Contribution à l'étude des éléments du groupe du platine en milieu urbain et péri-urbain / Distribution of platinum group elements in urban and peri-urban environment

Omrani, Mehrazin 12 December 2018 (has links)
Le platine (Pt), le palladium (Pd) et le rhodium (Rh), font partie des Eléments du Groupe du Platine (EGP), utilisés dans les catalyseurs automobiles. En raison de leur émission dans l'environnement, ces éléments peuvent aujourd'hui être considérés comme des contaminants émergeants et traceurs de la contamination automobile. Cette étude porte sur la dispersion des EGP depuis leur source (monolithes et émission à l'échappement) jusqu'au champ proche (atmosphère, poussières de chaussées, eaux de ruissellement, sédiment,sol de bord de route). Leur mobilité à partir de monolithes a été étudiée en présence d'eau de ruissellement et de molécules organiques. Leur spéciation a été évaluée dans les poussières de chaussées et les sédiments. Les teneurs en EGP dans les monolithes étudiés montrent le remplacement de Pt par Pd dans les catalyseurs récents. L'abondance relative des EGP dans les échantillons environnementaux est Pd > Pt > Rh. Les expérimentations de mobilisation montrent que la mobilisation des EGP est plus significative au contact des molécules organiques, est dépendante du pH de la solution et augmente avec l'âge du monolithe. Rh est l'élément le plus mobilisable dans les monolithes. La spéciation montre que les EGP sont peu mobiles. Dans la part mobilisable, ils sont majoritairement liés à la fraction dite organique. / Platinum (Pt), palladium (Pd) and rhodium (Rh) (platinum-group elements; PGEs),are used in automotive catalytic converters to remove harmful emissions from exhaust gas. Nevertheless, nowadays, the PGEs are emerging as new environmental emission contaminators due to their increasing use. The goal of this research is to study the distribution of PGEs from the source (i.e. automotive catalytic converters and exhaust gas) to the environmental samples (i.e. atmospheric particles, road dust,storm water, pond sediments, and road-side soil). The mobility of PGEs from the converters in contact with run off water and natural complexing agents were studied. Also, the speciation of PGEs was investigated in road dust and pond sediments. Comparison of PGE contents in different catalysts confirms the replacement of Pt by Pd in more recent converters. Besides, the relative abundance of PGEs in environmental samples shows higher concentration of Pd compared toPt and Rh (i.e. Pd>Pt>Rh). The results of testing PGEs mobilization in catalytic converters demonstrate more significant mobilization by organic molecules as compared to run off water. Our results also show the dependency of PGEs mobilization on pH and on catalyst age. Among the PGEs, Rh was the most mobilized element in catalytic converters. More importantly, the speciation test shows that while PGEs are low mobile elements, in the mobilizable fraction, PGEs are in the organic fraction.
87

Contaminantes emergentes: ocorrência e distribuição espaço-temporal no rio do Monjolinho e avaliação da remoção pela estação de tratamento de esgotos de São Carlos / Emerging contaminants: occurrence and spatiotemporal distribution in the Monjolinho river and evaluation of removal rate by the sewage treatment plant of São Carlos city.

Campanha, Mariele Barboni 27 March 2015 (has links)
Made available in DSpace on 2016-06-02T20:35:03Z (GMT). No. of bitstreams: 1 6749.pdf: 21604971 bytes, checksum: ea6b5030f47becaef3fc6875b8d6bc0e (MD5) Previous issue date: 2015-03-27 / Universidade Federal de Minas Gerais / This work aimed to investigate the occurrence of 12 emerging contaminants (pharmaceuticals, hormones and triclosan) in samples of influents and effluents, as well the removal in the sewage treatment plant (STP) of São Carlos. It was also investigated the occurrence and spatiotemporal distribution of emerging contaminants in surface waters and sediments from the Monjolinho River, the receptor of effluents, and one of its tributaries, the Água Quente Stream (AQS), which receives the discharge of non treated sewage. Influent and effluent samples were collected weekly. Surface water and sediment samples were obtained every two and four months, respectively, in points since the source until the mouth of the Monjolinho River. The target compounds in dissolved fraction of aquous samples were extracted by solid phase extraction (SPE), while for sediments it was performed ultrassonic extrations with solvents followed by SPE. The analytical determinations were made by ultra high pressure liquid chromatography coupled to mass spectrometer equipped with triplequadrupole analyser (LC-MS/MS). The hormone 17-&#945;-ethynilestradiol was not detected in any sample. However, all the pharmaceuticals evaluated and triclosan were detected in influent samples. The STP with upflow anaerobic sludge blancket (UASB) and air dissolved flotation in São Carlos presented low removal for carbamazepine, diclofenac, propranolol and ibuprofen. On the other hand, triclosan presented the highest removal (91.2%). In surface waters and sediments from Monjolinho river the concentration of contaminants presented an increasing trend since the source of the river to the downstream of the STP effluent discharge and after the confluence of the AQS (which flows into the river at the same place), where it was observed the highest concentrations in the Monjolinho River. The AQS, in its turn, presented higher concentrations of pharmaceuticals and triclosan than the Monjolinho River, due to the discharge of non treated sewage. Carbamazepine and diclofenac were persistent in both STP and aquatic body. The strong correlations between this compounds and electrical conductivity (considered a conservative parameter) sugests that CMZ and DCF can be tracers of both treated and non treated sewage release in the study area. Ee conclude that the main sources of phamaceuticals and triclosan to the Monjolinho River are the discharge of non treated sewage (from the AQS) and effluent from STP, since their removal is very low. Unlike the studies involving endocrine disruptors, the effects of other classes of emerging contaminants have been yet little explained in literature. Therefore, more surveys on the occurrence of these compounds combined with ecotoxicological studies must be conducted to make clear the magnitude of the impact that these substances can cause in the environment. Based on this information, adjustments in the effluent treatment may be investigated in the future, if there is interest in effectively removing this compounds in STP. / Neste trabalho foi investigada a ocorrência de 12 contaminantes emergentes (fármacos, hormônios e triclosan) em amostras de esgoto bruto e tratado, bem como foi avaliada a remoção dos mesmos pela estação de tratamento de esgoto (ETE) de São Carlos. Também investigou-se a ocorrência e distribuição espaço-temporal desses compostos em águas superficiais e sedimentos do rio do Monjolinho, o corpo aquático receptor, e em um de seus afluentes, o Córrego da Água Quente (CAQ), o qual recebe esgoto sanitário não tratado. Amostras de esgoto, águas e sedimentos foram coletadas semanalmente, bimestralmente e a cada quatro meses, respectivamente. No rio do Monjolinho, os pontos de amostragem abrangeram desde a nascente até a foz. Os compostos alvo na fração dissolvida das amostras aquosas foram extraídos por extração em fase sólida (SPE), enquanto que para sedimentos foi realizada extração ultrassônica com solventes, seguida de SPE. As determinações analíticas foram feitas por cromatografia de ultra eficiência acoplada à espectrometria de massas com analisador triplo quadrupolo (UPLC-MS/MS). O hormônio 17-&#945;-etinilestradiol não foi detectado em nenhuma das matrizes avaliadas. Porém, todos os fármacos avaliados e triclosan foram detectados nas amostras de esgoto bruto. O tratamento de esgoto empregando reator anaeróbio de fluxo ascendente (UASB) seguido de flotação por ar dissolvido (FAD) na ETE de São Carlos apresentou baixa remoção para carbamazepina, diclofenaco, propranolol e ibuprofeno, enquanto o triclosan apresentou a maior remoção (91,2%). Nas águas superficiais e sedimentos do rio do Monjolinho as concentrações dos contaminantes foram crescentes desde a nascente até após a confluência do CAQ e o lançamento do efluente da ETE (os quais ocorrem no mesmo local), onde ocorreram as maiores concentrações encontradas no rio do Monjolinho. O CAQ apresentou concentrações mais elevadas de fármacos e triclosan do que o rio do Monjolinho, devido ao aporte de esgoto não tratado. Carbamazepina e diclofenaco foram persistentes tanto em amostras de esgoto quanto no corpo aquático. Fortes correlações entre ambos os compostos e condutividade elétrica (este considerado um parâmetro conservativo) sugerem que os dois fármacos são bons traçadores do aporte de esgoto sanitário tratado e/ou não tratado na área de estudo. Conclui-se que as principais fontes de fármacos e triclosan no rio do Monjolinho são o lançamento de esgoto não tratado (por meio do CAQ) e esgoto tratado, uma vez que a remoção dos mesmos na ETE, é bastante baixa. Ao contrário dos estudos envolvendo desreguladores endócrinos, os efeitos adversos de outras classes de contaminantes emergentes ainda têm sido pouco elucidados na literatura. Portanto, mais pesquisas sobre a ocorrência desses compostos aliados a análises ecotoxicológicas devem ser realizados para que se dimensione a magnitude do impacto que essas substâncias podem causar ao ambiente. Com base em tais informações, adequações no tratamento de esgoto podem ser investigadas, no futuro, caso haja interesse em remover efetivamente esses compostos na ETE.
88

Determinação voltamétrica de triclocarban e carbendazim em produtos de higiene pessoal e água potável

Lúcio, Maria Mônica Lacerda Martins 26 August 2015 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2016-05-11T12:53:38Z No. of bitstreams: 1 arquivo total.pdf: 6105657 bytes, checksum: 8404a0fcb54e3893c95fdfb017f0ac96 (MD5) / Made available in DSpace on 2016-05-11T12:53:38Z (GMT). No. of bitstreams: 1 arquivo total.pdf: 6105657 bytes, checksum: 8404a0fcb54e3893c95fdfb017f0ac96 (MD5) Previous issue date: 2015-08-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Triclocarban (TCC) is a bactericide and fungicide widely used in personal care products, while carbendazim (MBC) is a fungicide widely used in cereal crops and a variety of fruits and vegetables, both are considered environmental contaminants. In this paper, propose the study of oxidation and determination of TCC using glassy carbon electrode (ECV) and the use of a carbon paste electrode modified with carbon nanotubes functionalized multi walled (EPC-NTCPMF) to determine MBC. Electrochemical detection of TCC and MBC was studied using different voltammetric techniques on a wide range of pH and the determination was performed on samples of soaps, only the TCC and drinking water at low concentrations, for both contaminants. For TCC, various oxidation processes were observed, however the peak P1 had greater sensitivity and selectivity in acetate buffer, pH 5.4 and was therefore used for the development of voltammetric methods, direct VOQ and adsorptive stripping voltammetry. For adsorptive stripping voltammetry, the linear response range was from 1.8 to 21 × 10-9 mol L-1 with a detection limit (LD) of 3.2 × 10-10 mol L-1, 1,000 times smaller than the LD obtained by direct VOQ. The method of adsorptive stripping voltammetry showed satisfactory levels of repeatability, 4.1% and reproducibility, 5.4% and was applied to determine TCC in soaps samples and an average recovery of 95.3% and drinking water with an average recovery apparent 95.4%. The MBC peaked main oxidation, almost reversible; the better sensitivity was achieved in H2SO4, pH 1.0 on the EPC-NTCPMF using VOQ. The linear response range is between 3 and 150 × 10-10 mol L-1 to LD 1.1 × 10-11 mol L-1. The method developed showed acceptable levels of repeatability, 4.6% and reproducibility, 6.2% and was applied for MBC determination in drinking water samples obtained average apparent recovery of 95.6%. The results obtained in the development of methods for determination of TCC and MBC showed excellent applicability for the studied samples, in addition to having advantages such as low cost instrumentation, analytical fast response, high sensitivity and selectivity. / Triclocarban (TCC) é um bactericida e fungicida amplamente utilizado em produtos de higiene pessoal, enquanto que o carbendazim (MBC) é um fungicida muito utilizado em culturas de cereais e numa grande variedade de frutas e vegetais, e ambos são considerados contaminantes ambientais. Nesse trabalho, propõe-se o estudo da oxidação e determinação do TCC utilizando eletrodo de carbono vítreo (ECV) e o uso de um eletrodo de pasta de carbono modificado com nanotubos de carbono de múltiplas paredes funcionalizado (EPC-NTCPMF) para determinação de MBC. A detecção eletroquímica de TCC e MBC foi estudada utilizando diferentes técnicas voltamétricas sobre uma ampla faixa de pH e a determinação foi realizada em amostras de sabonetes para TCC e em água potável em baixas concentrações para os dois contaminantes. Para TCC, foram observados seis processos de oxidação, entretanto, o processo correspondente ao pico P1 apresentou maior sensibilidade e seletividade em tampão acetato pH 5,4, portanto, foi utilizado para o desenvolvimento das metodologias voltamétricas, VOQ direta e VOQ com redissolução adsortiva. Para a VOQ com redissolução adsortiva, a faixa de resposta linear foi de 1,8 a 21 × 10-9 mol L-1 com limite de detecção (LD) de 3,2 × 10-10 mol L-1, 1.000 vezes menor do que o LD obtido por VOQ direta. O método de redissolução adsortiva apresentou níveis satisfatórios de repetibilidade, 4,1% e reprodutibilidade, 5,4% e foi aplicado para determinação de TCC em amostras de sabonetes, obtendo uma recuperação média de 95,3% e água potável com uma média de recuperação aparente de 95,4%. O MBC apresentou um pico de oxidação principal, quase reversível e a maior sensibilidade foi alcançada em H2SO4, pH 1,0, sobre o EPC-NTCPMF, utilizando VOQ. A faixa de resposta linear está entre 3 e 150 × 10-10 mol L-1 com LD de 1,1 × 10-11 mol L-1. O método desenvolvido apresentou níveis satisfatórios de repetibilidade, 4,6% e reprodutibilidade, 6,2% e foi aplicado para determinação de MBC em amostras de água potável, obtendo-se valor médio de recuperação aparente de 95,6%. Os resultados obtidos no desenvolvimento dos métodos para determinação de TCC e MBC demonstraram excelente aplicabilidade para as amostras estudadas, além de apresentarem vantagens como instrumentação de baixo custo, rápida resposta analítica, elevada sensibilidade e seletividade.
89

Ocorrência e distribuição de fármacos, cafeína e bisfenol-a em alguns corpos hídricos no Estado do Rio de Janeiro

Gonçalves, Eline Simões 03 May 2016 (has links)
Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2016-05-03T17:20:12Z No. of bitstreams: 1 Tese_Eline_VersãoFinal.pdf: 24730530 bytes, checksum: 660259a520e774bdef4c1478084f292b (MD5) / Made available in DSpace on 2016-05-03T17:20:12Z (GMT). No. of bitstreams: 1 Tese_Eline_VersãoFinal.pdf: 24730530 bytes, checksum: 660259a520e774bdef4c1478084f292b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências-Geoquímica. Niterói, RJ / A contaminação dos ambientes aquáticos por contaminantes emergentes é, ainda, pouco investigada no Brasil. Este estudo teve como objetivo avaliar a ocorrência de fármacos de diferentes classes terapêuticas, cafeína e bisfenola, em corpos hídricos de diferentes escalas no Estado do Rio de Janeiro. Foram eles: em micro escala, os Córregos São Domingos e Ribeirão Santíssimo (município de Santa Maria Madalena); em pequena escala, as bacias dos rios Paquequer, Guandu, Iguaçu e Sarapuí; em média escala, a bacia do médio rio Paraíba do Sul. Considerando os objetivos propostos foram analisadas 47 amostras para a determinação de 34 fármacos (acetaminofeno, ácido salicílico, codeína, diclofenaco, fenazona, ibuprofeno, ketoprofeno, meloxicam, naproxeno, piroxicam, atorvastaina, benzafibrato, gemfibrozil, alprazolam, carbamazepina, diazepam, lorazepam, venlafaxina, atenolol, metoprolol, nadolol, propanolol, sotalol, furosemida, torasemida, glibenclamida, irbesartan, losartan, valsartan, warfarina, tiabendazol, xilazina, sulfametoxazol, trimetoprim), cafeína e bisfenol-a, empregando a técnica analítica de extração em fase sólida, cromatografia a líquido de alta eficiência e espectrometria de massa tandem. Os resultados obtidos mostraram que nenhuma amostra analisada estava livre da contaminação por esses compostos e apenas dois deles (piroxicam e torasemida) não foram detectados em qualquer amostra. A freqüência com que os demais compostos foram detectados variou entre 2,1 (para a xilazina) e 100% (para ácido salicílico, velanfaxine, propanolol, tiabendazol, trimetoprim e cafeína). Uma avaliação qualitativa sobre consumo de medicamentos no município de Santa Maria Madalena mostrou uma estreita relação entre o consumo, a concentração e a frequência com que são encontrados fármacos em amostras ambientais. Os rios que apresentaram as maiores concentrações totais destes contaminantes foram (em ordem decrescente): rios Iguaçu-Sarapuí (51,8 μg L-1); córregos São Domingos e Ribeirão Santíssimo (19,0 μg L-1); rio Paquequer (18,2 μg L-1); rio Guandu (1,46 μg L-1) e rio Paraíba do Sul (1,42 μg L-1). Esses resultados mostram a importância da vazão na diluição da contaminação por fármacos, cafeína e bisfenol-a, oriundos da entrada de esgoto doméstico, o que pode ser avaliada através das cargas de contaminantes transportadas em cada bacia. A alta concentração de certos compostos (alguns quantificados neste estudo na ordem de μg L-1) não é, necessariamente, a principal preocupação ambiental, mas também, a sua persistência e atividade biológica. Contudo, para a maioria desses compostos não existem dados suficientes quanto a ocorrência, avaliação de risco e ecotoxicidade, e desta forma, é difícil prever os seus efeitos causados à saúde do homem e dos organismos aquáticos, o que torna primordial a sua investigação / The contamination of aquatic environments by emerging contaminants is still poorly investigated in Brazil. This study aimed to evaluate the occurrence of different therapeutic classes of drugs, caffeine and bisphenol-a in water bodies of different scales in the State of Rio de Janeiro. They were: in micro-scale, the streams of São Domingos and Ribeirão Santíssimo (in the city of Santa Maria Madalena); in a small-scale, the River Basins Paquequer, Guandu, Iguaçu and Sarapuí; on the medium scale, the basin of the middle Paraíba do Sul River. Considering the objectives proposed, 47 samples were analyzed for the determination of 34 pharmaceutical compounds (acetaminophen, salicylic acid, codeine, diclofenac, phenazone, ibuprofen, ketoprofen, meloxicam, naproxen, piroxicam, atorvastatin, benzafibrate gemfibrozil, alprazolam, carbamazepine, diazepam, lorazepam, venlafaxine, atenolol, metoprolol, nadolol, propranolol, sotalol, furosemide, torasemide, glibenclamide, irbesartan, losartan, valsartan, warfarin, thiabendazole, xylazine, sulfamethoxazole, trimethoprim), caffeine and bisphenol-a, using the analytical technique of Solid Phase Extraction, High Performance Liquid Chromatography and Mass Spectrometry tandem. The results showed that any sample evaluated was free from contamination by these compounds; only two compounds (piroxicam and torasemide) were not detected in any sample. The frequency of compounds detected ranged from 2.1 (for xylazine) and 100% (for salicylic acid, velanfaxine, propranolol, thiabendazole, trimethoprim and caffeine). A qualitative assessment about drug use in the municipality of Santa Maria Madalena showed a close relationship between the consumption, the concentration and the frequency wherein pharmaceutical compounds are found in environmental samples. The rivers that had the highest total concentrations of these contaminants were (in descending order): Iguaçu and Sarapuí rivers, (51.8 mg L-1), and the streams São Domingos and Ribeirão Santíssimo (19.0 mg L-1); Paquequer River (18.2 mg L- 1); Guandu River (1.46 mg L-1) and Paraíba do Sul River (1.42 mg L-1). These results show the importance of flow in the dilution of the contamination by pharmaceutical compounds, caffeine and bisphenol-a, from the entry of domestic sewage, which can be evaluated through loads of contaminants carried in each basin. The high concentration of certain compounds (some quantified in this study in order mg L-1) is not necessarily the main environmental concern, but also its persistence and biological activity. However, for most of these compounds there are insufficient data regarding the occurrence, risk assessment and ecotoxicology, and thus it is difficult to predict the health effects in humans and aquatic organisms, which makes its primary research
90

Analyse de contaminants d’intérêt émergent dans l’Estuaire et le Golfe du Saint-Laurent par chromatographie liquide couplée à la spectrométrie de masse haute résolution

Picard, Jean-Christophe 12 1900 (has links)
Les contaminants d’intérêt émergent (CIEs) ont fait l’objet d’un nombre croissant d’études ces dernières années, notamment dans les milieux aquatiques. Il existe cependant certains manques de connaissances concernant leur occurrence et leur distribution dans les systèmes hydrologiques complexes, notamment la distribution verticale à travers différentes masses d’eau. Les variations saisonnières entre conditions estivales et hivernales restent difficiles à établir en raison des conditions météorologiques hivernales rigoureuses au Canada, limitant l’accessibilité des échantillons. Ainsi, ce projet de maîtrise a porté sur l’étude de 90 CIEs, comprenant des pesticides, des produits pharmaceutiques et marqueurs anthropiques, des hormones et des substances perfluorées dans un environnement océanographique, soit l’Estuaire et le Golfe du Saint-Laurent (EGSL). Deux expéditions ont été menées en conditions hivernales (hivers 2019 et 2020) et une en conditions estivales (été 2019). Ces missions ont permis d’évaluer, dans un premier temps, la distribution spatiale des CIEs dans l’eau de surface le long de l’EGSL, puis, dans un second temps, la variation des concentrations de surface associées aux différentes températures, salinités, couvertures de glace, processus de dégradation ou débit du fleuve des saisons. Par ailleurs, un échantillonnage à plusieurs profondeurs durant l’hiver 2020 a permis de dresser un profil vertical des concentrations le long de l’Estuaire et du Golfe du Saint-Laurent. Finalement, la filtration de larges volumes d’eau de surface durant l’hiver 2020 a permis d’évaluer la concentration des CIEs adsorbés sur la matière en suspension (phase particulaire) et conséquemment, le partitionnement entre la phase dissoute et particulaire, influencé par la variation de la salinité et de la quantité de matière en suspension. Les analyses ont été effectuées grâce au développement et à la validation d’une nouvelle méthode multi-résidus impliquant la chromatographie liquide à ultra-haute performance (UHPLC) couplée à la spectrométrie de masse à haute résolution (HRMS). À notre connaissance, il s’agit de la première étude à caractériser divers contaminants émergents dans les eaux de l’Estuaire et du Golfe du Saint-Laurent, particulièrement pendant la période hivernale et à travers la colonne d’eau. / Contaminants of Emerging Concern (CECs) have been increasingly studied since recent years, for instance in aquatic ecosystems. However, there exist significant knowledge gaps regarding their occurrence and distribution in complex hydrological systems, including their vertical distribution in different water bodies. Seasonal variations between summer and winter conditions are also difficult to establish because of the rigorous winter weather conditions in Canada, restricting the accessibility of samples. Thus, this project focused on the study of 90 CECs, including pesticides, pharmaceuticals and anthropogenic markers, hormones, and perfluorinated substances in an oceanographic environment, namely the St. Lawrence Estuary and Gulf (SLEG). Two expeditions were conducted under winter conditions (winters 2019 and 2020) and one under summer conditions (summer 2019). These expeditions first assessed the spatial distribution of CECs along the SLEG and, secondly, the seasonal and annual variations of the concentrations associated with the different temperatures, salinities, ice cover, degradation processes or seasonal river flow. In addition, sampling at multiple depths during the winter of 2020 allowed for documenting the vertical profiles of CECs throughout the SLEG. Finally, the filtration of large volumes of surface water during the winter of 2020 allowed for the evaluation of the CECs adsorbed onto suspended particle matter (SPM) and consequently, the partitioning between dissolved and particulate phases, influenced by salinity and SPM variations. Analyses were performed following the development and validation of a new multi-residue method involving ultra-high performance liquid chromatography (UHPLC) coupled with high-resolution mass spectrometry (HRMS). To the best of our knowledge, this is the first study to report the occurrence of emerging contaminants in the SLEG, especially during the winter season and across the water column.

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