Global warming issues are a widespread problem around the world and the emissions of greenhouse gases is one of the main contributors. The transport sector emits a significant amount of greenhouse gas emissions; thus, this contributes to global warming. To tackle this challenge the Swedish state introduced in July 2018 a system called bonus-malus system which aims to increase the proportion of eco-friendly cars and in the long run reducing greenhouse gases emissions from the transport sector. This paper examines the tax system within the Bonus-Malus system. Primarily investigating if Malus, tax system, impacted the demand for electric vehicles since it introduced. The study conducted based on a short panel data from Sweden´s 21 counties for the period 2016-2020 and the analysis method applied is a regression analysis. The results of this thesis confirm a strong positive relationship between the share of newly registered battery electric vehicles (BEV) and the Malus, but much weaker influence of the other studied variables. Suggesting that tax system induce on emission seem to be efficient at boost the demand for BEV

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The United States is the world's largest oil consumer demanding about twenty five percent of the total world oil production. Whenever there are difficulties to supply the increasing quantities of oil demanded by the market, the price of oil escalates leading to what is known as oil price spikes or oil price shocks. The last oil price shock which was the longest sustained oil price run up in history, began its course in year 2004, and ended in 2008. This last oil price shock initiated recognizable changes in transportation dynamics: transit operators realized that commuters switched to transit as a way to save gasoline costs, consumers began to search the market for more efficient vehicles leading car manufactures to close 'gas guzzlers' plants, and the government enacted a new law entitled the Energy Independence Act of 2007, which called for the progressive improvement of the fuel efficiency indicator of the light vehicle fleet up to 35 miles per gallon in year 2020. The past trend of gasoline consumption will probably change; so in the context of the problem a gasoline consumption model was developed in this thesis to ascertain how some of the changes will impact future gasoline demand. Gasoline demand was expressed in oil equivalent million barrels per day, in a two steps Ordinary Least Square (OLS) explanatory variable model. In the first step, vehicle miles traveled expressed in trillion vehicle miles was regressed on the independent variables: vehicles expressed in million vehicles, and price of oil expressed in dollars per barrel. In the second step, the fuel consumption in million barrels per day was regressed on vehicle miles traveled, and on the fuel efficiency indicator expressed in miles per gallon. The explanatory model was run in EVIEWS that allows checking for normality, heteroskedasticty, and serial correlation. Serial correlation was addressed by inclusion of autoregressive or moving average error correction terms. Multicollinearity was solved by first differencing. The 36 year sample series set (1970-2006) was divided into a 30 years sub-period for calibration and a 6 year "hold-out" sub-period for validation. The Root Mean Square Error or RMSE criterion was adopted to select the "best model" among other possible choices, although other criteria were also recorded. Three scenarios for the size of the light vehicle fleet in a forecasting period up to 2020 were created. These scenarios were equivalent to growth rates of 2.1, 1.28, and about 1 per cent per year. The last or more optimistic vehicle growth scenario, from the gasoline consumption perspective, appeared consistent with the theory of vehicle saturation. One scenario for the average miles per gallon indicator was created for each one of the size of fleet indicators by distributing the fleet every year assuming a 7 percent replacement rate. Three scenarios for the price of oil were also created: the first one used the average price of oil in the sample since 1970, the second was obtained by extending the price trend by exponential smoothing, and the third one used a longtime forecast supplied by the Energy Information Administration. The three scenarios created for the price of oil covered a range between a low of about 42 dollars per barrel to highs in the low 100's. The 1970-2006 gasoline consumption trend was extended to year 2020 by ARIMA Box-Jenkins time series analysis, leading to a gasoline consumption value of about 10 millions barrels per day in year 2020. This trend line was taken as the reference or baseline of gasoline consumption. The savings that resulted by application of the explanatory variable OLS model were measured against such a baseline of gasoline consumption. Even on the most pessimistic scenario the savings obtained by the progressive improvement of the fuel efficiency indicator seem enough to offset the increase in consumption that otherwise would have occurred by extension of the trend, leaving consumption at the 2006 levels or about 9 million barrels per day. The most optimistic scenario led to savings up to about 2 million barrels per day below the 2006 level or about 3 millions barrels per day below the baseline in 2020. The "expected" or average consumption in 2020 is about 8 million barrels per day, 2 million barrels below the baseline or 1 million below the 2006 consumption level. More savings are possible if technologies such as plug-in hybrids that have been already implemented in other countries take over soon, are efficiently promoted, or are given incentives or subsidies such as tax credits. The savings in gasoline consumption may in the future contribute to stabilize the price of oil as worldwide demand is tamed by oil saving policy changes implemented in the United States.

Controlled Auto Ignition (CAI) combustion is a new combustion principle in internal combustion engines which has in recent years attracted increased attention. In CAI combustion, which combines features of spark ignition (SI) and compression ignition (CI) principles, air/fuel mixture is premixed, as in SI combustion and auto-ignited by piston compression as in CI combustion. Ignition is provided in multiple points, and thus the charge gives a simultaneous energy release. This results in uniform and simultaneous auto-ignition and chemical reaction throughout the whole charge without flame propagation. CAI combustion is controlled by the chemical kinetics of air/fuel mixture with no influence of turbulence. The CAI engine offers benefits in comparison to spark ignited and compression ignited engines in higher efficiency due to elimination of throttling losses at part and idle loads. There is a possibility to use high compression ratios since it is not knock limited, and in significant lower NOx emission (≈90%) and particle matter emission (≈50%), due to much lower combustion temperature and elimination of fuel rich zones. However, there are several disadvantages of the CAI engine that limits its practical application, such as high level of hydrocarbon and carbon monoxide emissions, high peak pressures, high rates of heat release, reduced power per displacement and difficulties in starting and controlling the engine. Controlling the operation over a wide range of loads and speeds is probably the major difficulty facing CAI engines. Controlling is actually two-components as it consists of auto-ignition phasing and controlling the rates of heat release. As CAI combustion is controlled by chemical kinetics of air/fuel mixture, the auto-ignition timing and heat release rate are determined by the charge properties such as temperature, composition and pressure. Therefore, changes in engine operational parameters or in types of fuel, results in changing of the charge properties. Hence, the auto-ignition timing and the rate of heat release. The Thesis investigates a controlled auto-ignition (CAI) combustion in internal combustion engines suitable for transport applications. The CAI engine environment is simulated by using a single-zone, homogeneous reactor model with a time variable volume according to the slider-crank relationship. The model uses detailed chemical kinetics and distributed heat transfer losses according to Woschini's correlation [1]. The fundamentals of chemical kinetics, and their relationship with combustion related problems are presented. The phenomenology and principles of auto-ignition process itself and its characteristics in CAI combustion are explained. The simulation model for representing CAI engine environment is established and calibrated with respect to the experimental data. The influences of fuel composition on the auto-ignition timing and the rate of heat release in a CAI engine are investigated. The effects of engine parameters on CAI combustion in different engine concepts fuelled with various fuels are analysed. The effects of internal gas recirculation (IEGR) in controlling the auto-ignition timing and the heat release rate in a CAI engine fuelled with different fuels are investigated. The effects of variable valve timings strategy on gas exchange process in CAI engine fuelled with commercial gasoline (95RON) are analysed.

Répondant à une forte demande de sécurité, d’économie de poids et d’optimisation du volume utile, les réservoirs pour carburants sont actuellement généralement constitués d’une paroi barrière polymère multicouche visant à limiter les émissions de vapeurs dans l’atmosphère. Etre capable de prédire les perméabilités est primordial pour l’optimisation de telles structures. Grâce à des automates conçus au laboratoire, les mesures de sorption et de perméabilité ont été réalisées pour trois polymères leaders du domaine (PEHD, Liant et EVOH) et des mélanges modèles de carburants composés d’éthanol, d’iso-octane et de toluène. Les propriétés de sorption ont été modélisées par UNIQUAC et un nouveau modèle inédit SORPFIT. Les paramètres des lois de diffusion, de type TSVF2 ou Long généralisé, ont aussi été optimisés pour chaque polymère malgré une difficulté particulière pour l’EVOH. Une méthodologie originale a été ensuite proposée pour la prédiction des flux partiels des multicouches à partir des paramètres caractéristiques des monocouches correspondantes. Selon la nature et la disposition de chaque couche, deux cas de figures ont été identifiés : la limitation cinétique et la limitation thermodynamique du transfert, cette dernière étant estimée à partir des modèles de sorption initialement optimisés. La confrontation des calculs avec les mesures expérimentales réalisées pour des films bicouches et tricouches d’Arkema montre des prédictions très satisfaisantes. Cette approche est finalement étendue à la simulation de la perméabilité de structures multicouches plus complexes et plus représentatives des réservoirs pour carburants industriels / Responding to a strong demand for security, weight reduction and volume optimization, the fuel tanks are currently usually made of polymer multi-layer barriers in order to limit vapour emissions into the atmosphere. The prediction of their permeability remains a world-wide critical challenge for the multi-layer optimization. Thanks to original semi-automated experimental set-ups, sorption and permeability measurements were carried out for three leading polymer materials (HDPE, EVOH and Binder) and model fuel mixtures of ethanol, iso-octane and toluene. The modelling of the sorption properties was successfully achieved by the UNIQUAC model and a new model called SORPFIT. The parameters of the diffusion laws according to the TSVF2 or the generalized Long models were also optimized for each polymer despite some difficulty with EVOH. An original methodology was then proposed for predicting the partial fluxes of polymer multi-layers from the characteristic parameters of the corresponding mono-layers. Depending on the nature and disposition of each layer, two scenarios were identified: the kinetics limitation and the thermodynamics limitation of mass transfer, the latter being estimated from the sorption models initially optimized. The comparison of the calculated fluxes with the experimental data obtained for bi-layer and tri-layer films provided by the world-wide industrial company Arkema showed that the predictions were very satisfying. This approach was then extended to the simulation of the permeability of more complex multi-layer structures which are more representative of commercial fuel tanks

Ce travail de thèse étudie l’influence de la morphologie des feuillets de sulfure de molybdène sur la sélectivité des catalyseurs d’hydrotraitement. Les feuillets de phase active présentent en effet deux types de bords appelés « M-edge » et « S-edge » susceptibles de conduire à des réactivités différentes. Le changement de la morphologie 2D des feuillets pourrait modifier les proportions de bords M et S exposés et ainsi les propriétés catalytiques des catalyseurs sulfures. Pour cela, des catalyseurs non promus (Mo) et promus (CoMo), supportés sur alumine ont été préparés par imprégnation à sec puis sulfurés dans des conditions variées (gaz et température). Des tests catalytiques en hydrodésulfuration (HDS) sélective des essences de FCC (sélectivité HDS/HYD) ont ensuite permis d’évaluer l’impact de la morphologie en s’appuyant sur des modèles géométriques construits à partir de calculs DFT et de caractérisations expérimentales (TEM, IR (CO), TPR, XPS). Les résultats obtenus pour les catalyseurs de type Mo semblent ainsi confirmer l’influence de la morphologie 2D sur la sélectivité HDS/HYD, le bord M paraissant être le plus sélectif pour les catalyseurs non promus. Ils mettent également en évidence l’importance de la réductibilité plus ou moins marquée des bords sur les propriétés catalytiques, notamment sur le bord M. Le changement des conditions de sulfuration semble donc affecter la morphologie des particules mais également les propriétés chimiques propres à chaque bord. En ce qui concerne les catalyseurs promus, la variation des conditions de sulfuration semble agir essentiellement au niveau de la répartition du promoteur entre les bords M et S. Cependant, les interactions avec le support paraissent constituer un frein aux effets de promotion. Dans ce contexte, les sulfurations à haute température sous H2S pur permettent d’obtenir des gains significatifs en activité et sélectivité. Ces résultats semblent dus à de faibles interactions avec le support et une décoration privilégiée du bord S qui pourrait favoriser la réaction d’HDS et limiter la réaction d’HYD. Au final, les interprétations effectuées en terme de morphologie 2D tendent à confirmer que ce paramètre peut constituer un axe de développement intéressant pour les catalyseurs d’hydrotraitement. L'optimisation des conditions de sulfuration permettraient bien de faire varier la morphologie et le taux de décoration du promoteur des catalyseurs, améliorant ainsi significativement l'activité et la sélectivité / This thesis examines the influence of the morphology of particles of molybdenum sulfide on selectivity of hydrotreating catalysts. Nanoparticles of active phase present two types of edges called “M-edge” and “S-edge” which may lead to different reactivities. The change in morphology of the 2D sheets could change the proportions of M and S edges exposed and thus the catalytic properties of sulfide catalysts. For this, non-promoted (Mo) and promoted (CoMo) catalysts, supported on alumina were prepared by dry impregnation and sulfide in various conditions (gas and temperature). Catalytic tests in selective hydrodesulfurization (HDS) of FCC gasoline (selectivity HDS /HYD) were then used to assess the impact of the morphology based on geometrical models which were constructed with DFT calculations and experimental characterizations (TEM, IR (CO), TPR, XPS). The results for Mo catalysts seem to confirm the influence of the 2D morphology selectivity HDS / HYD, M-edge appearing to be the most selective for non-promoted catalysts. They also highlight the importance of the reducibility more or less pronounced of the edges on the catalytic properties, especially on the M-edge. The different conditions of sulfidation seem to affect the morphology of the particles but also the specific chemical properties at each edge. Regarding to the promoted catalysts, the different conditions of sulfidation appear to act primarily at the distribution of the promoter between the M and S edges. However, interactions with the carrier appear to constitute an obstacle to promoting effects. In this context, sulfidations at high temperature in pure H2S lead to obtain significant gains in activity and selectivity. These results appear to be due to weak interactions with the carrier and to the presence of the promoter on the S-edge which could promote the HDS reaction and limit the HYD reaction. Finally, the interpretations made in terms of 2D morphology tend to confirm that this parameter can be an interesting line of development for hydrotreating catalysts. Optimization of the sulfidation conditions could effectively allow to vary the morphology and the rate of decoration of promoted catalysts which significantly improve the activity and selectivity

Le secteur des transports est fondamental pour le développement économique d'un pays et pour assurer la communication et une bonne qualité de vie. Cependant, le transport routier conduit à une grave dégradation de la qualité de l'air et contribue au réchauffement de la planète. Parmi tous les polluants, les particules fines et ultrafines, émises par les véhicules mais également formées dans l'atmosphère sont considérées toxiques. De nombreuses études montrent que l’exposition chronique aux particules fines favorise le développement de pathologies respiratoires et cardiovasculaires. Les précurseurs gazeux, les principaux mécanismes réactionnels ainsi que les transformations physiques que les Aérosol Organiques Secondaires (AOS) subit dans l'atmosphère restent encore incertains. La présente étude porte principalement sur la caractérisation des polluants primaires émis par les échappements automobiles et les transformations photochimiques des COV / COVI. Les émissions des voitures ont été évaluées à l’aide d’un banc à rouleau au laboratoire de l’IFSTTAR. Les mesures du nombre de particules ont été effectuées directement au niveau de l’échappement. Pour les véhicules GDI, PN0.23 (<23 nm) représentait en moyenne 20- 30% du nombre total de particules émises, alors que pour les voitures diesel, cette fraction était bien inférieure (≈10-15%). Lors des régimes à grande vitesse (autoroutier Artemis) des véhicules diesel, une régénération passive de Filtre à Particules (FAP) a été observée. Les particules émises étaient principalement constituées de suie, de bisulfate et de matière organique. Les particules émises par les voitures essence à injection directe étaient principalement composées de Black Carbon (BC) et de gouttelettes organiques contenant des éléments. Pendant le démarrage à froid, les voitures GDI émettent des concentrations importantes de BC et de matière organique. Les émissions d'hydrocarbures ont également été étudiées. Les véhicules GDI ont émis des concentrations importantes de THC lors du démarrage à froid. Parmi les composés aliphatiques, des composés jusqu’à la C15 ont été identifiés, confirmant l’émission d'hydrocarbures plus lourds par les voitures diesel. La deuxième partie de ce travail consistait à étudier la transformation atmosphérique de certains COV (toluène, naphtalène, cyclohexane, nonane) émis par les véhicules Euro 5 et Euro 6 et à déterminer le potentiel de formation d’AOS de ces composés. Les composés choisis ont été photo-oxydés (seuls et en mélange) dans un réacteur à tube à flux d'aérosol afin de simuler leur vieillissement atmosphérique. Les résultats majeurs suggèrent: (1) des composés aromatiques et des HAP représentent les composés avec le plus fort potentiel de formation d'AOS ; (2) la température a un impact important sur la formation et le rendement d'AOS ; (3) la présence de particules préexistantes a un effet positif sur la formation d'AOS; (4) il a été constaté que la présence des NOx affectaient négativement la formation d'AOS ; (5) la formation d'AOS de mélanges de COV est fortement influencée par la fraction de composé aromatique. Certains des produits identifiés dans la phase particulaire n’ont jamais été signalés auparavant. La dégradation des composés aromatiques en régime de NOx moyen a produit des composés nitro-aromatiques identifiés à la fois en phase gazeuse et en phase particulaire. Cette thèse contribue à enrichir la base de données d’émissions des voitures, encore limitée aux véhicules Euro 5 et Euro 6. La spéciation des composés non réglementés aidera à mieux comprendre le budget atmosphérique d’AOS et les impacts des voitures sur la qualité de l’air. Enfin, l’étude de photoxydation de COV primaires (seuls, mélange et émissions complètes) conduira à une meilleure compréhension de la formation d’AOS / The transport sector is fundamental to the economic development of a country and to ensure communication and a good quality of life. However, road transport contributes significantly to global warming and leads to serious degradation of the air quality. Among all pollutants, fine and ultrafine particles, emitted by vehicles but also formed in the atmosphere are considered as potentially toxic. Many studies show that chronic exposure to fine particles promotes the development of respiratory and cardiovascular diseases. The main gaseous precursors, the atmospheric chemical pathways as well as the chemical composition and the physical transformations that secondary organic aerosol (SOA) undergo in the atmosphere, remain poorly understood. The main aim of this work was on one side to improve the knowledge about primary pollutants emitted from Euro 5 and Euro 6 diesel and gasoline passenger cars and on the other side to investigate the photochemical transformations of the VOCs/IVOCs emitted from these cars. Passenger car emissions have been evaluated on a chassis dynamometer test bench at the IFSTTAR laboratory. Particle number measurements were carried out directly at the tailpipe. For GDI vehicles PN0.23 (< 23 nm) represented on average 20 -30 % of total particle number emitted, while for diesel cars, this fraction was considerably lower (≈10-15%). During high speed regimes (Artemis motorway) of diesel passenger cars Diesel Particulate Filter (DPF) passive regeneration was observed. These periods were characterized by a high particle number concentration; their composition was mainly soot, bisulfate and some organic material. PM emitted from gasoline DI passenger cars was mainly composed by BC and some organic droplets containing traces of other elements. During cold start GDI cars do emit important concentrations of BC and organic material. Emission of hydrocarbons has also been investigated. Gasoline DI emitted important concentration of THCs during cold start. Among the aliphatic compounds, families until C15 have been identified, confirming emission of heavier HCs from diesel cars. The second aim of this work was the study of atmospheric degradation of selected VOCs (toluene, naphthalene, cyclohexane, nonane) emitted from Euro 5 and Euro 6 vehicles and to determine the SOA formation potential of these compounds under different environmental conditions. The chosen compounds have been photoxidized (alone and in mixture) in an Aerosol Flow Tube (AFT) reactor in order to simulate VOCs atmospheric aging. The results suggest: (1) aromatic and PAHs compounds, own highest potential to form SOA; (2) the temperature has an important impact on SOA formation and yield; (3) the presence of pre-existing seed particles has, in general, a positive effect on SOA formation and (4) NOx has been found to negatively affect SOA formation; (5) SOA potential formation of VOC mixtures is highly influenced by the fraction of aromatics. Some of the products identified in the particle phase have never been previously reported. Degradation of aromatic compounds under medium NOx regime produced nitro-aromatic compounds identified both in the gas and particle phase. This PhD contributes to enrich vehicle emissions database, still limited for Euro 5 and Euro 6 cars. Speciation of non-regulated compound will help to better understand atmospheric SOA budget and car emissions air quality impacts. By last, the photoxidation study of primary VOCs (alone, mixture and full emissions) will lead to a better comprehension of SOA formation from vehicles

[pt] Neste trabalho, métodos analíticos baseados na fosforimetria na temperatura ambiente foram desenvolvidos para a determinação de sete compostos policíclicos aromáticos (CPA) sulfurados e nitrogenados presentes do petróleo. Mais especificamente, o objetivo foi o de fornecer ferramentas analíticas que permitissem avaliar e quantificar estes CPA em gasolina e em uma amostra ambiental (sedimento). Adicionalmente, a informação obtida através da fosforimetria mostrou potencial para permitir diferenciar amostras (por exemplo, a identificação de amostras contaminadas) por meio de perfil em três dimensões ou curvas de nível. A aplicação de técnica de varredura sincronizada e o uso do efeito externo seletivo do átomo pesado aumentaram o grau de seletividade e de discriminação entre amostras, pois induziu fosforescência de componentes específicos na amostra e melhorou a resolução espectral dos resultados. Inicialmente, foi feito um estudo das características fosforescentes das substâncias em diferentes condições experimentais, seguido da maximização do sinal fosforescente de cada uma das substâncias nas condições experimentais mais propícias para observação do sinal fosforescente. Para tal, o papel filtro, previamente tratado para redução do sinal de fundo, foi utilizado como substrato sólido para imobilização dos analitos, permitindo a observação de intensa fosforescência na temperatura ambiente. Os parâmetros de mérito das metodologias desenvolvidas para cada um dos analitos em questão foram obtidos. As faixas lineares se estenderam entre 1,0 x 10-7 e 5,0 x 10-4 mol L-1, considerando as concentrações das soluções dos analitos aplicadas no substrato. Os coeficientes de determinação (r2) obtidos ficaram sempre acima de 0,9784. Os limites de detecção absolutos (para 5 µL de amostra) foram todos na ordem do ng, mostrando a capacidade para detecção sensível em termos de massa efetiva de analito. Os testes de repetibilidade mostraram valores variando entre 12 e 18%, o que pode ser considerado satisfatório para a técnica realizada em substrato sólido. Também foram conduzidos estudos de robustez e reprodutibilidade. Alternativamente, sinais fosforescentes foram maximizados em condições experimentais secundárias do ponto de vista da magnitude de sinal, mas potencialmente relevantes do ponto de vista da seletividade. Testes de recuperação indicaram, na maioria dos casos, resultados bastante satisfatórios no caso das misturas sintéticas contendo quantidades eqüimolares de componentes (nesse caso, foram testadas várias combinações de analitos e de interferentes) ou contendo interferentes, em concentrações cinco vezes maior que a do analito de interesse. Nos casos mais críticos em termos de interferências, recursos instrumentais ou quimiométricos foram aplicados para melhorar a seletividade e possibilitar a quantificação. Os métodos desenvolvidos foram testados em amostras simuladas de gasolina, em gasolina comercial e em uma matriz ambiental (sedimento) fortificadas com os analitos de interesse. As recuperações obtidas foram bastante satisfatórias e compreendidas entre 90% e 117%. Estudos envolvendo varreduras de fosforescência total (TPS) também foram realizados, com o intuito de se obter uma impressão digital característica para cada um dos analitos. Testes de TPS em gasolina comercial indicaram a presença de pelo menos seis dos sete analitos estudados, devido à obtenção de perfis espectrais muito semelhantes aos dos padrões. Testes adicionais mostraram a capacidade de identificar contaminações (misturas) na gasolina pela adição de diesel e de querosene. / [en] In this work, analytical methods based on room-temperature phosphorimetry were developed aiming the quantification of seven polycyclic aromatic compounds (PAC) containing sulfur and nitrogen present in petroleum. More specifically, the goal was to obtain analytical tool to allow the evaluation and the quantification of these PCA in sediment and gasoline. In addition, the phosphorimetric information displayed potential for the discrimination of samples (for instance, the identification of contaminated samples) by means of three dimension plots or level curves. The application of synchronized sweeping technique and the use of the selective external heavy atom effect had increased the degree of selectivity and discrimination between samples, since it induces phosphorescence from specific components of the sample and improved the spectral resolution of the results. Initially, a study of the phosphorescent characteristics of the compounds in different experimental conditions was made, followed of the signal maximization in the most appropriate experimental conditions for the observation of phosphorescence. Filter paper, previously treated for background reduction, was employed as solid substrate for the immobilization of analytes. The analytical figures of merit for each one of the methods had been obtained. The linear range varied between 1,0 x 10-7 mol L-1 and 5,0 x 10-4 mol L-1, taking into consideration the concentration of the solutions spotted on the substrate. The determination coefficient values (r2) were always above of 0.9784. The absolute limits of detection (5 µL sample) were in ng order, showing the sensitivity of the developed methods. The repeatability tests had enabled values varying between 12 and 18%, which can be considered satisfactory for solid substrate technique. Robustness and reproducibility studies were also carried out. Additionally, secondary experimental conditions, in terms of signal magnitude, were optimized since these could be relevant from the selective point of view. Recovery tests indicated, in most of the cases, satisfactory results for synthetic mixtures containing equimolar quantities of components (in these cases, several analyte/interferent combinations were tested) and containing interferents in concentrations five times higher than the one of the analytes. In the most critical cases in terms of interferences, instrumental or quimiometric approaches had been applied to improve selectivity and make the quantification possible. The developed methods had been tested in simulated gasoline samples, commercial gasoline and in a sediment sample fortified with the analytes of interest. The obtained recoveries had been considered satisfactory and within 90 and 117%. Total phosphorescence scanning (TPS) studies had been also carried out in order to get the characteristic fingerprint for each one of the compounds of interest. TPS tests in gasoline had indicated the presence of six out of seven of the studied analytes, since very similar fingerprints were obtained. Additional tests had demonstrated the capability of this procedure to detect gasoline contaminations with diesel or kerosene.

Em muitos países e principalmente no Brasil, compostos oxigenados tais como etanol e metil terta-butil-éter (MTBE) têm sido adicionados à gasolina em cerca de 26% do seu volume para aumentar a octanagem do motor e diminuir a emissão de monóxido de carbono e os níveis de ozônio na atmosfera. O derramamento de tais gasolinas, referidas como gasolina oxigenada tem um efeito cosolvente, provocando um aumento da concentração dos hidrocarbonetos na água subterrânea. A taxa de dissolução em água da gasolina oxigenada, que é dependente das propriedades químicas dos compostos orgânicos, determinam o grau e a severidade de contaminação da água subterrânea nas vizinhanças do derramamento. O objetivo do trabalho foi analisar e quantificar o potencial de contaminação da água subterrânea e de solos arenosos residuais dos arenitos da Formação Botucatu por derramamento de gasolina oxigenada. As análises realizadas buscam fornecer dados para a modelagem numérica em casos envolvendo derramamento de gasolina. Ensaios de equilíbrio em lote e de dissolução em colunas foram realizados objetivando a determinação da concentração aquosa de hidrocarbonetos da gasolina em equilíbrio de fases e a avaliação do tempo estimado para total dissolução em água dos hidrocarbonetos da gasolina pura. Ambos os ensaios analisaram também o efeito cosolvente do etanol na mistura. Verificou-se a validade da lei de Raoult e do modelo log-linear na determinação da concentração aquosa da gasolina pura e oxigenada. Em colunas de solos não saturados avaliou-se a difusão na fase vapor dos compostos orgânicos da gasolina em função do tempo. Finalizando as análises, fez-se uma simulação numérica do transporte da gasolina em zonas não saturadas fazendo-se uso do programa R-UNSAT. / In many countries and mainly in Brazil oxygenated compounds such as ethanol and MTBE have been added to gasoline up to 26% to increase the octane level and to reduce carbon monoxide and ozone levels in the air. The spill of such gasolines, referred as oxygenated gasoline has a potential cosolvent effect, resulting in an increased groundwater concentration of hydrocarbons. The rate of oxygenated gasoline dissolution, which is dependent of the chemical properties of the compounds, determines the degree and severity of groundwater contamination in the vicinity of the spill. The goal of this research was to analyze and to quantify the potential of contamination of the groundwater and of the residual sandy soils from Botucatu sandstone due to the spill of oxigenated gasoline. The performed analysis supply data to the numerical model in case of gasoline spills. Laboratory batch and column leaching tests were carried out in order to determine the equilibrium aqueous concentration of the hydrocarbons compounds of gasoline and to evaluate the time scale for aqueous dissolution of the hydrocarbons compounds. Both tests have analyzed the cosolvent effect of ethanol in the mixture. It was verified the validity of the Raoult's law and the log-linear cosolvency model to estimate the solubility of the hydrocarbons compounds from unamended gasoline and from oxygenated gasoline. Column tests with unsaturated undisturbed soil samples were carried out to investigate the vapor-phase diffusion of aromatic hydrocarbons compounds with time. Finally the transport of gasoline in unsaturated zones was simulated with the R-UNSAT model.

Este trabalho teve como objetivo principal propor procedimentos de avaliação de metodologia de coleta e análise de solventes no ar em ambiente de trabalho. Utilizou-se o metanol em mistura MEG (Metanol 33%, Etanol 60% e Gasolina 7%) como exemplo. Na época, a mistura MEG estava sendo indicada para substituir o etanol combustível, devido a sua falta no mercado. Foi montada uma atmosfera controlada dinâmica por injeção, para gerar concentrações conhecidas de vapor metanol em mistura MEG. Essa atmosfera permaneceu estável ao redor de 7,5 horas. O limite de detecção método analítico do CG-DIC, utilizado para o acompanhamento das concentrações geradas, foi de 18mg/m3 para um volume amostrado de 2mL coletado por uma válvula de coleta. Estando a atmosfera controlada apta para os testes de validação, foram realizados estudos de volume de \"breakthrough\" para coleta de metanol em tubos de sílica gel, com a finalidade de se conhecer o volume a ser amostrado em campo. Esses estudos foram realizados levando em conta as possíveis interferências de etanol, gasolina e elevada umidade relativatotal . O tempo de coleta de amostra para a mistura com umidade relativa recomendado para uma vazão de 200mL/min foi de 15 minutos. O método analítico utilizado, para a determinação de metanol coletado em tubos de sílica gel e analisado por CG-DIC. foi uma adaptação de métodos encontrados na literatura do NIOSH, para as condições da mistura. Após encontrar a melhor seletividade para o menor tempo de retenção do metanol em mistura MEG, foi determinado o limite de detecção de 9,7x 10-3&#181;g. A precisão do método analítico encontrada foi de 2,1% e a exatidão esteve entre 89% e 97%. Estabelecida a metodologia analítica, as melhores condições de atmosfera controlada e o volume de coleta de amostra, foram realizados estudos que integram a coleta e análise ou seja, precisão e exatidão de coleta e análise e estabilidade de armazenamento. Para estudos de precisão e exatidão de coleta e análise, foram geradas concentrações de metanol em mistura MEG, com umidade ao redor de 0,5, 1 e 2 vezes o limite de tolerância brasileiro(156ppm); dessorção em água e análise por CGDIC. O coeficiente de variação total calculado para o método de coleta e análise de metanol em mistura MEG foi de 7,3% (precisão) e wazzu exatidão esteve entre 90% e 101%. As concentrações de metanol foram estáveis, em tubos adsorventes armazenados em geladeira, durante o período de estudo de 14 dias. Porém, foi constatada uma migração de metanol através da camada analítica para a camada controle de forma gradativa com o passar do tempo. As soluções, a partir da dessorção dos tubos armazenadas em geladeira, foram estáveis durante o período de estudo de 45 dias. Além desses experimentos foram também realizados estudos de capacidade de adsorção da sílica gel para metanol levando em conta os interferentes, e verificado se eram capazes de dessorver totalmente o metanol, após um certo período de coleta. Constatou-se que após 30 minutos de coleta, os interferentes (etanol, umidade e gasolina) entravam em equilíbrio com o adsorvente e o metanol. / The main objective of this work is to propose procedures for the evaluation of the methodology of the sampling and analysis of solvents in the air in the workplace. Methanol in a MEG mixture (Methanol 33%, Ethanol 60%, and Gasoline 7%) was used as an example. At that time the MEG mixture was being proposed to substitute ethanol fuel due to its shortages on the Brazilian market. An atmosphere, dynamically controlled by injection, was produced to generate the known concentrations of methanol vapour in MEG mixtures. This atmosphere remained stable for about 450 minutes. The detection Iimit, using the GC-FID analytical method to monitor the concentrations produced, was 18mg/m3 for a sample volume of 2mL sampled from a sampling valve. The controlled atmosphere being suitable for the validation tests, studies of the breakthrough volume for the sampling of methanol in silica gel tubes were carried out, with the aim of discovering the total volume to be sampled in the field. These studies were carried out taking into account the possible interference of ethanol, gasoline and the high relative humidity. The sampling time for the mixture with the recommended relative humidity with a flow rate of 200mL/min was fifteen minutes. The analytical method used for the determination of methanol sampled in silica gel tubes and analyzed by GC-FID, was based on the methods found in the NIOSH and OSHA literature, adapted to the mixture conditions. After finding the best selectivity for the lowest retention time for the methanol in the MEG mixture, the detection Iimit of 9.7 x 10-3&#181;g was determined. The precision of the analytical method was 2.1% and the accuracy was between 89% and 97%. Having established the analytical methodology. the best conditions for the controlled atmosphere and the sampling volume, studies were carried out which integrated the sampling and the analysis, that is, the precision and the accuracy of the sampling and the analysis and the storage stability. To study the precision and the accuracy of the sampling and analysis, concentrations 1 or 2 times that of the Brazilian tolerance Iimit of methanol (156 ppm) in MEG mixture, with humidity around 0.5, were generated, using dessorption in water and analysis by GC-FID. The total coefficient of variation calculated for the method of sampling and analysis of methanol in MEG mixture was 7.3% (precision) and the accuracy was between 90% and 101% . The concentrations of methanol were stable, in adsorption tubes stored in the refrigerator, throughout the study period of fifteen days. However, a gradual migration of methanol through the analytical layer to the control layer with the passage of time was noted. The solutions from the dessorption of the tubes, stored in the refrigerator, were stable throughout the study period of 45 days. Besides these experiments, studies of the adsorption capacity of silica gel for methanol, taking into account the interferents, were also carried out, and it was verified whether these were capable of the total dessorption of the methanol, after a certain sampling period. It was noted that after thirty minutes of sampling, the interferents came into equilibrium with the adsorbent and the methanol.