Afin de pallier aux problèmes dus aux limites de détection des capteurs et des détecteurs usuels, un système de préconcentration est indispensable. Ce microcomposant permet d’accumuler le ou les vapeur(s) à détecter à l’aide d’un adsorbant et permet de les libérer sous l’effet d’une montée brutale de la température vers un détecteur. Une amplification de la concentration et donc du signal est ainsi obtenue.Cette thèse poursuit le développement d’un préconcentrateur pour la détection de vapeurs toxiques et d’explosifs. Ce préconcentrateur sera constitué d’un microcomposant en silicium rempli d’un adsorbant et muni d’une résistance de chauffage sur sa face inférieure. Des capillaires métalliques permettent d’assurer la circulation du gaz dans le dispositif. Différents types de préconcentrateurs ont été développés avec différents adsorbants afin satisfaire les conditions pour des applications concernant les composés organiques volatils (COV) et les explosifs. L’optimisation des phases d’adsorption et de désorption est cruciale pour le procédé.Le couplage entre un micro-chromatographe et un préconcentrateur a été réalisé et a montré l’apport de ce microcomposant pour la chromatographie. L’analyse d’un mélange de COV a pu être réalisée avec des concentrations initiales de l’ordre de 40 ppb alors que la limite de détection de l’appareillage était de quelques ppm. Un facteur d’enrichissement de 800 a été atteint.L’avantage de l’utilisation du silicium poreux a également été mis en évidence pour l’adsorption de gaz avec des faibles pressions de vapeur saturante. Cette propriété est intéressante pour la préconcentration de vapeur d’explosifs. / In order to overcome problems due to the conventional sensors detection limits, a preconcentration system is required. Accumulation of vapor(s) for detection is possible with an adsorbent and allows releasing them toward a detector, under the effect of a sudden rise of the temperature. Amplification of the concentration and the signal are obtained.This thesis continues the development of a preconcentrator for the detection of toxic gas and explosives. This preconcentrator is made of a silicon microcomponent filled with an adsorbent and a heater at its back. Two metal capillary allow ensuring the gas flow into the device. Various designs of preconcentrators were developed with different adsorbents to satisfy the requirements for volatile organic compounds (VOCs) and explosives applications.The optimization of adsorption and desorption phases is very important for the process.The coupling between a micro-chromatograph and a preconcentrator was conducted and showed the contribution of the microcomponent to the chromatography. Analysis of a VOCs mixture was achieved with initial concentrations in the order of 40 ppb, whereas the detection limit was of a few ppm. An enrichment factor of 800 was achieved.The advantage of using porous silicon was also demonstrated for the gas adsorption with low saturation vapor pressure. This result is interesting for explosive vapor préconcentration.

La pollution atmosphérique résulte d’un mélange complexe de composés, des gaz et des particules, dont les effets sont notoirement néfastes. Les composés organiques volatils (COV) tiennent un rôle prépondérant dans la chimie atmosphérique et sont précurseurs d’ozone et d’aérosols organiques secondaires (AOS). En Île-de-France, l’exposition à la pollution est préoccupante ; or, des incertitudes significatives sont toujours associées aux sources de polluants, ainsi qu’à leur intensité et leurs variabilités à différentes échelles de temps et très peu d’investigations ont porté sur la quantification de l’exposition individuelle. Dans ce contexte, cette thèse a cherché à mieux caractériser les variabilités temporelle et spatiale de la pollution en Île-de-France.La fiabilité discutable des capteurs portables a été dépassée par l’élaboration d’un protocole de sélection et de qualification comprenant différents tests en mesures fixes, en chambre et en mobilité. Cette nouvelle méthodologie, basée notamment sur l’utilisation d’un outil combinant différents indicateurs statistiques, a été appliquée pour retenir l’AE51, le Cairclip et le Canarin, mesurant respectivement le carbone suie (BC), le dioxyde d’azote (NO2) et les particules (PM).Ces trois capteurs ont été déployés au cours de campagnes de mesures impliquant une trentaine de volontaires. L’exposition individuelle ainsi quantifiée est plus élevée à l’automne qu’au printemps et varie de manière substantielle en fonction des différents environnements fréquentés. La proximité de la circulation routière (pour le BC et le NO2) ainsi que les activités de cuisine et la fumée de tabac (pour les PM) présentent des contributions importantes à l’exposition totale (jusqu’à 34 %, 26 % et 44 % respectivement), alors même que le temps passé dans ces environnements est faible.En plus du trafic routier, le BC est traditionnellement imputé au feu de bois. Une campagne hivernale de mesures (3,5 mois) a permis d’imputer respectivement 22 % et 47 % des COV mesurés à ces deux sources. Certains composés ont été mesurés et associés au feu de bois pour la première fois en air ambiant comme le benzènediol et le méthylbutènone. Une comparaison avec l’inventaire régional des émissions a permis d’identifier des similitudes et des différences pour proposer des améliorations. / Air pollution results from a complex mixture of compounds, gases and particulate matter, whose effects have proven to be harmful. Volatile organic compounds (VOCs) play a major role in atmospheric chemistry and are precursors of ozone and secondary organic aerosols (SOAs). In Île-de-France, exposure to pollution is a concern; however, significant uncertainties are still associated with the pollutants’ sources, as well as their intensity and variability at different time scales, and very few investigations have focused on quantifying personal exposure. In this context, this research sought to better characterize the temporal and spatial variabilities of pollution in Île-de-France.The questionable reliability of portable sensors has been addressed by the design of a selection and qualification protocol including various tests in static measurements, controlled chamber and mobility. This new methodology, based in particular on the use of a tool combining different statistical indicators, was applied to choose the AE51, Cairclip and Canarin, measuring black carbon (BC), nitrogen dioxide (NO2) and particulate matter (PM) respectively.These three sensors were deployed during measurement campaigns involving about thirty volunteers. The personal exposure thus quantified is higher in fall than in spring and varies substantially according to the different environments frequented. Proximity to road traffic (for BC and NO2) as well as cooking activities and tobacco smoke (for PM) make significant contributions to total exposure (up to 34 %, 26 % and 44 % respectively), even though the time spent in these environments is short.In addition to road traffic, BC is traditionally attributed to wood burning. A winter measurement campaign (3.5 months) attributed respectively 22 % and 47 % of the measured VOCs to these two sources. Compounds including benzenediol and methylbuteone were measured and associated with wood burning for the first time in ambient air. A comparison with the regional emissions inventory identified similarities as well as differences and suggested improvements.

Les composés organiques volatils (COV) jouent un rôle majeur au sein du système atmosphérique puisqu’ils interviennent en tant que précurseurs d’ozone troposphérique et d’aérosols organiques secondaires (composés aux divers impacts sanitaires et climatiques) ; d’où le réel besoin de mieux les caractériser. A ce jour, de fortes incertitudes demeurent quant à leur nature, leur quantification et la contribution de leurs sources d’émissions respectives.Cette thèse propose, au travers d’expérimentations de laboratoire et de terrain, une caractérisation exhaustive des COV et de leurs principales sources d’émissions en région Île-de-France. Les méthodes mises en place dans ce travail de thèse reposent sur la détermination de profils de spéciation caractéristiques du trafic routier, du chauffage au bois et du gaz naturel à partir d’investigations en champ proche (en tunnel, en cheminée et à partir d’un conduit de gaz domestique). Ces différents profils de source ont été utilisés comme empreinte chimique de référence pour l’identification des principales sources d’émissions de COV, dont les contributions respectives ont été estimées à l’aide du modèle source-récepteur Positive Matrix Factorization (PMF), appliqué sur une année d’acquisition de mesures COV (HCNM+COVO) à Paris. Ce travail de thèse a ainsi permis, pour la première fois, d’étudier la variabilité saisonnière des COV et de leurs sources majeures. Les émissions liées au trafic routier ont été révélées comme la principale source de COV d’origine locale/régionale à Paris (contribuant à ¼ des émissions totales à l’échelle annuelle). L’impact prépondérant du chauffage au bois en hiver (50 % de la masse totale COV mesurée) a également été mis en évidence. Les résultats de cette étude de répartition de sources ont été confrontés à l’inventaire des émissions d’Airparif. Nous avons souligné un bon accord entre nos observations et l’inventaire pour les sources liées au trafic automobile et au chauffage au bois.Cette évaluation indépendante des inventaires est essentielle puisque ces derniers sont aujourd’hui utilisés comme données d’entrée au sein des modèles de prévision de qualité de l’air. / Volatile organic compounds (VOCs) play a key role within the atmospheric system acting as precursors of ground-level ozone and secondary organic aerosols (causing health and climatic impacts); hence the growing interest of better characterizing them. Significant uncertainties are still associated with compounds speciation, quantification and respective contributions from the different emission sources.This thesis proposes, through several laboratory and intensive field campaigns, a detailed characterization of VOCs and their main emissions sources within the Île-de-France region. We used methods based on the determination of speciation profiles indicative of road traffic, wood burning and natural gas sources obtained from near-field investigations (inside a tunnel, at a fireplace and from a domestic gas flue). These different source profiles were used as chemical fingerprints for the identification of the main VOC emission sources, which respective contributions were estimated using the Positive Matrix Factorization (PMF) source-receptor model applied to one-year VOCs (including NMHC+OVOC) measurements in Paris. This thesis allowed, for the first time, to evaluate the seasonal variability of VOCs and their main emission sources. Road traffic-related emissions are major VOC local/regional sources in Paris (contributing to a quarter of total annual emissions). The important impact of wood burning in winter (50 % of the VOC total mass) was observed. Results obtained from this approach were compared with the regional emissions inventory provided by the air quality monitoring network Airparif. Finally, a good agreement was found between our observations and the inventory for road traffic and wood burning-related sources.This independent assessment of inventories is of great interest because they are currently used as input data within air quality prediction models.

La sensibilisation du grand public à la pollution intérieure, les exigences croissantes des réglementations/recommandations le tout combiné à une nécessité de se démarquer de la concurrence, font de la limitation de la concentration des COV (COV : Composés Organiques Volatiles) dans l’air habitacle un enjeu crucial pour l’industrie automobile. En effet, à l’intérieur des véhicules, les COV sont principalement issus de l’air extérieur par combustion et évaporation du carburant mais, contrairement aux autres polluants, peuvent également avoir une origine intérieure à l’habitacle de par la désorption de substances chimiques utilisées lors de la fabrication des matériaux présents dans le véhicule. La capture des COV par adsorption sur charbons actifs ou zéolithes est à ce jour l’une des techniques d’abattement des COVs les plus efficaces et les moins coûteuses mais souffre de certaines limitations (sélectivité, régénération). L’objectif de cette thèse a consisté à étudier une alternative avec l’emploi d’une autre classe d’adsorbants ‘hybrides’ : les Metal-Organic Frameworks (MOFs). Formés de briques inorganiques connectées par des ligands organiques, ces matériaux poreux cristallisés présentent une grande diversité structurale ainsi qu’une composition chimique (métal, ligand) et une porosité (taille des pores, surface spécifique et volume poreux) extrêmement modulables. Cela vient de la possibilité quasi-infinie de faire varier à la fois le centre métallique et le ligand organique, ce que l’on ne retrouve pas à cette échelle chez les zéolithes et les charbons actifs. Le travail a consisté à évaluer les performances d’une série d’une dizaine de MOFs, possédant des propriétés chimiques (acidité, redox, hydrophiles/hydrophobes, …) et structurales (taille et forme des pores, réseaux rigides ou flexibles…) différenciées mais aussi de leur stabilité avérée (eau, température) et mise à l’échelle déjà établie. En plus des caractérisations usuelles (diffraction des rayons X, analyse thermogravimétrique, spectroscopie Infra-Rouge, porosimétrie N2 à 77K), la spectroscopie Infra-Rouge operando a été utilisée pour simuler le comportement de ces MOFs en présence de COV dans des conditions aussi proches que possible de la réalité. Les adsorbants les plus prometteurs ont ensuite été mis à l’échelle (50-100 g) et mis en forme (pastilles) puis testés en chambre de simulation environnementale. / The indoor air pollution awareness of general public and the increasing demands of regulations / recommendations, combined with a need to stand out from the competition, make limiting the concentration of VOCs (VOCs : volatile organic compounds ) in the air cockpit crucial for the automotive industry. For example, inside a vehicle, the VOCs are originated from the outside air by combustion and evaporation of fuel. However, unlike other pollutants, it may also have an inner origin from the desorption of existing chemical substances used in the manufacture of the vehicle. Thus, the capture of VOCs by adsorption is one of the challenging techniques today. In this context, activated carbon and zeolite based VOC abatement are effective and least expensive but suffers some limitations in stability, selectivity and regeneration. The aim of this thesis was to study an alternative class of 'hybrid' adsorbents i.e. Metal-Organic Frameworks (MOFs). These porous crystalline materials are built by the association of inorganic bricks connected by organic ligands. They have highly tunable structural diversity,chemical composition (metal:ligand) and porosity (pore size, surface area and pore volume). Moreover, they possess almost infinite ability to vary both the metal center and the organic ligand that is not found at this level in zeolites and activated carbons. The work was to evaluate the performance of a series of ten MOFs, having diverse architecture (size and shape of the pores, rigid or flexible networks ...), chemical properties (acidity, redox, hydrophilic / hydrophobic, ...) and stability (water temperature). In addition to the usual characterization (X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, porosimetry N2 at 77K), Infra-Red spectroscopy operando was performed to simulate the behavior of these MOFs in the presence of VOCs in conditions as close as possible to the reality. Furthermore, the most promising adsorbents were scaled up (50-100 g) and formatted/fabricated as pellets and tested for environmental simulation chamber.

The first part of the work is aimed to the study of changes of electrical properties of substituted phthalocyanines under the influence of humidity. Thin films were prepared by spin coating technique. During the influenece of humidity electrical conductivity increases. Sorption and desorption and the changes in electrical properties under the repated humidity exposure were investigated as well. Impedance spectroscopy was used for the studies. The second part of this work consists of optical studies and changes of optical parametrsunder the influence of different alcohols (methanol, ethanol, 2-propanol) exposures. The investigated samples were prepared by vacuum evaporation a glow-discharge-induced sublimation. The changes of optical reflectances of the films upon exposure to alcoholvapour-containg atmospheres were studied as a function of alcohol concetration and exposure time.

This thesis aims to answer the question on how to introduce a paint reuse program in Stockholm, Sweden. In both the US and in the UK, paint reuse programs have been successfully introduced and are today working to create a more circular thinking about paint, how to minimize paint waste and to reuse or remanufacture paint. In the UK only, there are around 50 million litres of leftover paint, in which approximately 20 million litres could be recycled into new paint. The British Coatings Federation started investigating on how to build a more sustainable approach to paint, how to decrease the paint waste, that usually is incinerated or landfilled, by remanufacturing leftover paints into new paint. The British Coating Federation’s PaintCare started a paint reuse program, facilitating for paint to be remanufactured. This manual goes through all aspects of implementing a national paint reuse program and has been of great value of this thesis. Before implementing a paint reuse program, one must be aware of the many difficulties that comes with it. Paint is today regarded as waste, and for waste to be recycled into a new product, authorities need to grant a so-called End-of-Waste certificate, this could, due to the European Commission Waste Directive be done to waste by an approved process. One other implication when implementing a paint reuse program, or more specifically, paint remanufacturing, is to recognise the European Commission’s directive on REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) and ECHA (European Chemicals Agency). All leftover paints used in paint remanufacturing must be authorised by REACH and all the components/substances used in remanufacturing paint must be evaluated and approved by ECHA. There is a need for transparency in the paint remanufacturing, therefore samples must be taken of every batch of remanufactured paints so that the paint can be tested. Because of this, only paints manufactured in the EU can be used in remanufacturing. When considering starting a paint reuse program in Stockholm, all these aspects need to be solved. Therefore, to begin with, a public survey should be sent out to gather information about how much leftover paint could be collected in Stockholm, what the public thinks about leaving leftover paints for remanufacturing, and to evaluate if remanufactured/recycled paints would sell, if there is a market. A good starting point would be to set up a small-scale pilot plant, to sorting out/get to know the difficult aspects of staring a paint reuse program/remanufacturing to work, i.e. the supply of waste that can be collected, buy all the equipment needed for remanufacturing to work, the regulatory, and to get to know the market for remanufactured paint. / Målet med denna uppsats är att se hur ett färgåtervinningsprogram skulle kunna tas fram för Stockholm, Sverige. Färgåtervinning har introducerats framgångsrikt i både USA och Storbritannien, vilka idag arbetar för att bygga ett mer cirkulärt tänkande gällande färg, samt arbetar för att minska mängden färgavfall genom färgåtervinning. Enbart i Storbritannien finns det ungefär 50 miljoner liter överbliven färg där cirka 20 miljoner av dessa skulle kunna återanvändas. British Coatings Federation har undersökt möjligheten att bygga ett mer hållbart tänk kring färg för att minska mängden färgavfall som i dagsläget förbränns eller deponeras och istället återvinna färgen. PaintCare i Storbritannien har därför startat ett återvinningsprogram, för att på så sätt möjliggöra detta. De har konstruerat en manual vilken går igenom alla steg för en nationell implementation av ett sådant program, vilken varit till stor nytta för denna rapport. Utöver detta så har en stor del av uppsatsens innehåll kommit att handla om själva processen för att återvinna färg. Innan en implementation genomförs av ett färgåtervinningsprogram måste svårigheterna redogöras för. Färg ses idag som avfall och för att ett avfall ska sluta vara ett avfall och istället ses som en återvunnen produkt måste ett end-of-waste certifikat beviljas, vilket görs av statliga myndigheter på uppdrag av EU-kommissionens avfallsdirektiv. Ytterligare en svårighet i implementationen av ett färgåtervinningsprogram är att följa direktiven från REACH (Registration, Evaluation, authorisation and Restriction of Chemicals) och ECHA (European Chemicals Agency). All den färg som återvinns måste genomgå REACH’s krav och alla komponenter i den återvunna färgen måste kontrolleras av ECHA, detta måste göras innan färgen kan marknadsföras. Det är av stor vikt att produktionen är transparent och att prover tas för varje sats återvunnen färg, för att senare kunna genomgå olika tester och på grund av detta kan bara färg vilken är producerad inom EU användas i återvinning. När ett återvinningsprogram för färg övervägs, måste alla dessa aspekter undersökas. Till att börja med bör därför en offentlig undersökning göras för att samla information om mängden överbliven färg ett hushåll samlar i förråd, vilka åsikter allmänheten har gällande färgåtervinning, samt för att utvärdera om återvunna färger har en marknad i Stockholm. En bra utgångspunkt skulle vara att börja med en småskalig pilotanläggning. Detta för att förstå vad som krävs för att driva ett välfungerande återvinningsprogram, för att lära känna marknaden och för att komma igång med processen och få den att fungera på ett effektivt sätt.

Ground-level ozone is harmful to the human respiratory system, as well as the environment. The national EPA 8-hour ozone standard for ground-level ozone was reduced from 85 parts per billion (ppb) to 75 ppb in 2008, and trends from previous years show that some of the counties in Central Florida could be in danger of violation. Violation means "non attainment" status; in which the county is ordered by EPA to develop specific implementation plans to reduce its emissions. The objective of this study was to compile an emissions inventory of volatile organic compounds (VOCs) and nitrogen oxides (NOx) from nonroad equipment in Osceola, Seminole, and Orange Counties (OSO) in Central Florida, and to develop possible action steps to reduce those emissions. This is important because VOC and NOx emissions are precursors to ground-level ozone. Thus, compiling emissions inventories is important to identify high VOC and NOx emitters. Mobile and point sources have long been the highest emitters of VOC and NOx and have therefore been targeted and monitored since the Clean Air Act of 1970, but the nonroad sources (such as construction and lawn equipment) have only been regulated since the 1990s. Using the NONROAD and NMIM modeling programs, the highest nonroad emitters of VOC for Central Florida were found to be lawn/garden equipment, and boating equipment, emitting a combined percentage of 77% of the total nonroad mobile source VOC. Construction equipment contributed 67% of the total nonroad mobile source emissions of NOx in Central Florida. The components of these categories were also analyzed to find the largest individual sources of VOC and NOx. Of the individual sources, lawn mowers and outboard boat engines were found to be the largest sources of VOCs. Of the NOx sources, all the construction equipment components had a relatively similar level of NOx emissions. Next, action steps were developed to reduce emissions, focusing on the high emitters, along with an estimated cost and feasibility for each measure. Of these steps, implementing a ban on leafblowers, and reducing use of lawn mowers, edgers, trimmers, etc. seemed to be the most effective for reducing VOCs. Although these are effective measures, the cost and feasibility of both pose challenges. The best action step for reducing NOx emissions in construction equipment seemed to be by simply reducing idling of equipment on job sites. This also poses challenges in feasibility and enforcement by management. Further, constant on/off cycles could result in decreasing the useful life of the older construction equipment. Finally, a survey was conducted with various construction managers and companies to find out the typical equipment and quantity needed for land clearing/grubbing, as well as the typical use, idling time, and total project time for each piece of equipment on a 10-acre site, under various conditions. The purpose of the study was to develop a rough estimate for the average amount of VOC and NOx emissions that will be produced per acre of land clearing activities, and to estimate the emissions reductions and cost savings if idling of the equipment was reduced.

No description available.

No description available.

According to the World Health Organization, urban air pollution is a high public health priority due its linkage to cardio-pulmonary disease and association with increased mortality and morbidity (1, 2). Additionally, air pollution impacts climate change, visibility, and ecosystem health. The development of effective strategies for improving air quality requires accurate estimates of air pollutant emissions. In response to the need for new approaches to measuring emissions, we have designed a mobile Flux Lab for the Atmospheric Measurement of Emissions (FLAME) that applies a proven, science-based method known as eddy covariance for the direct quantification of anthropogenic emissions to the atmosphere. The mobile flux lab is a tool with novel, multifaceted abilities to assess air quality and improve the fidelity of emission inventories. Measurements of air pollutant concentrations in multiple locations at the neighborhood scale can provide much greater spatial resolution for population exposure assessments. The lab's mobility allows it to target specific sources, and plumes from these can be analyzed to determine emission factors. Through eddy covariance, the lab provides the new ability to directly measure emissions of a suite of air pollutants. We have deployed the FLAME to three different settings: a rural Appalachian town where coal transport is the dominant industry; schools in the medium-sized city of Roanoke, Virginia; and the large urban areas around Norfolk, Virginia, to measure neighborhood-scale emissions of air pollution. These areas routinely experience high ozone and particulate matter concentrations and include a diverse array of residential neighborhoods and industries. The FLAME is able to capture emissions from all ground-based sources, such as motor vehicles, rail and barge traffic, refuse fires and refueling stations, for which no direct measurement method has been available previously. Experiments focus on carbon dioxide (CO₂), the principal greenhouse gas responsible for climate change; nitrogen oxides (NOx), a key ingredient in ground-level ozone and acid rain; volatile organic compounds (VOCs), a second key ingredient in ozone and many of which are air toxics; and fine particulate matter (PM2.5), a cause of mortality, decreased visibility, and climate change. This research provides some of the first measurements of neighborhood-scale anthropogenic emissions of CO₂, NOx, VOCs and PM2.5 and as a result, the first opportunity to validate official emission inventories directly. The results indicate that a mobile eddy covariance system can be used successfully to measure fluxes of multiple pollutants in a variety of urban settings. With certain pollutants in certain locations, flux measurements confirmed inventories, but in others, they disagreed by factors of up to five, suggesting that parts of the inventory may be severely over- or underestimated. Over the scale of a few kilometers within a city, emissions were highly heterogeneous in both space and time. FLAME-based measurements also confirmed published emission factors from coal barges and showed that idling vehicles are the dominant source of emissions of air toxics around seven schools in southwest Virginia. Measurements from this study corroborate existing emission inventories of CO₂ and NOx and suggest that inventories of PM2.5 may be overestimated. Despite the tremendous spatial and temporal variability in emissions found in dense urban areas, CO₂ fluxes on average are very similar across the areas in this study and other urban areas in the developed world. Nevertheless, the high level of variability in spatial and temporal patterns of emissions presents a challenge to air quality modelers. The finding that emissions from idling vehicles at schools are likely responsible for creating hot spots of air toxics adds to the urgency of implementing no-idling and other rules to reduce the exposure of children to such pollutants. Ultimately, the results of this study can be used in combination with knowledge from existing emission inventories to improve the science and policies surrounding air pollution. / Ph. D.