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L'emballage alimentaire est l'un des principaux acteurs de la préservation de la sécurité alimentaire et de la qualité au cours du stockage. Toutefois, de transferts de masse se produisent entre le l'emballage polymère et les denrées alimentaires. Polylactide (PLA) est un nouveau polymère biosourcé utilisé dans les applications d'emballage. Pour cela son interaction avec des denrées alimentaires a été étudiée dans des conditions réelles d'utilisation. Une méthodologie originale basée sur l'extraction multiple de l'espace de tête (MHE) et l'extraction multiple de l'espace de tête couplée à la microextraction sur phase solide (MHS-SPME) pour la mesure de sorption de composés organiques volatils (COVs) dans le PLA a été développé à des activités faibles et dans le domaine vitreux du polymère. Les COVs ayant une structure chimique modérément hydrophobe et des similarités de structure avec le PLA montrent une forte affinité pour le polymère. Plus surprenant, la forte sorption de composés aromatiques, notamment du benzaldéhyde, a été montrée. En mélange avec d'autres COVs le benzaldéhyde favorise leur sorption par un effet synergique. De plus, même à des activités faibles (0,01) et en présence de benzaldéhyde, la sorption de COVs induit une cristallisation du PLA. En contact avec un aliment aqueux, le PLA se montre résistant à l'hydrolyse et la sorption des matières grasses est faible, même en utilisant des conditions de stockage proches de sa transition vitreuse. L'apparition de COVs pendant le procédé de transformation a été étudiée par MHS-SPME. Des lactides, l'acétaldéhyde et le 2,3-pentanedione étaient détectés après extrusion et thermoformage. Les quantités des deux derniers composés diminuaient cependant pendant le procédé de thermoformage. / Packaging plays a major role in the preservation of food but mass transfer between the packaging material and foodstuff occurs during shelf life leading to the quality deterioration. Polylactide (PLA) is a novel packaging material; therefore its interaction with food was investigated at service conditions. The sorption of ethyl esters, benzaldehyde and 2-nonanone at low concentrations and in mixture and the effects on the thermal properties of PLA were studied. Multiple Headspace Extraction (MHE) and Multiple Headspace coupled to Solid Phase MicroExtraction (MHS-SPME) developed here allow to show a high affinity for moderately hydrophilic molecules sharing structure similarities with PLA such as ethyl acetate. However, a very high affinity for the aromatic structure of benzaldehyde was revealed which seems to favor interaction and sorption of the aroma compounds present in the mixture. At 0.01 activities, a plasticization by aroma compounds was observed and a solvent induced crystallization seemed to be correlated to the sorption of benzaldehyde. The contact between a flavored food emulsion and PLA, using conditions near the PLA glass transition showed that PLA hydrolysis was moderate and oil and aroma compound sorption was low. The formation of VOC during the PLA manufacturing process was assessed by MHS-SPME. Lactides, acetaldehyde and 2,3-pentanedione are VOCs present in PLA after extrusion and thermoforming. The two latter compounds increased after extrusion and then decreased or disappeared after thermoforming.

A quantificação de 11 compostos carbonílicos (formaldeído, acetaldeído, acetona, acroleína, propionaldeído, crotonaldeído, butiraldeído, benzaldeído, isovaleraldeído, valeraldeído e 2,5-dimetilbenzaldeído) e a identificação de outros 43 compostos orgânicos voláteis (alcanos, alcenos, aromáticos, halogenados e nitrogenados) foram feitas em 9 ambientes diferentes de trabalho localizados em áreas internas do Hospital Universitário, USP, São Paulo. Dentre os compostos carbonílicos, os mais abundantes em ordem decrescente foram formaldeído, acetona, acetaldeído e acroleína. As maiores razões de mistura de formaldeído foram observadas nas salas de Macroscopia (169,9 e 90,2 ppbv) e Técnicas Histológicas (11,7 e 58,7 ppbv), em decorrência da atividade desenvolvida nos locais. Na sala de Macroscopia, os níveis de formaldeído encontrados foram acima do limite (100 ppbv) estabelecido por órgãos internacionais que controlam a qualidade do ar em ambientes internos não industriais. As razões de mistura entre o ambiente interno e o ambiente externo, razões I/E, permitiram indicar a predominância dos compostos carbonílicos nos ambientes internos. A acroleína foi encontrada na faixa de 6,4 a 9,3 ppbv nos ambientes internos estudados. Na área externa, entretanto, foram encontrados valores similares (6,4 e 6,8 ppbv) aos dos ambientes internos obtendo razões I/E próximas de 1. Os compostos podem ter sido emitidos por materiais de construção e acabamento, fumaça do tabaco, adesivos, via metabolismo microbiano e bacteriano ou podem ter sido transportados por correntes de ar do ambiente externo para o ambiente interno / The quantification of 11 carbonyl compounds (formaldehyde, acetaldehyde, acrolein, acetone, propionaldehyde, crotonaldehyde, butiraldehyde, benzaldehyde, isovaleraldehyde, valeraldehyde and 2,5-dimethylbenzaldehyde) and the identification of another 43 volatile organic compounds (alkanes, alkenes, aromatic, halogenated and nitrogenated compounds) have been done with samples of 9 different indoor places inside the University Hospital at USP in São Paulo. Among the carbonyl compounds, there where found higher quantities of formaldehyde, acetone, acetaldehyde and acrolein in this order. The highest ratios of formaldehyde mixture have been observed at the Macroscopic room (169.88 and 90.2 ppbv) and Histological Techniques (11.7 and 58.7 ppbv), due to the routine activities of these places. At the Macroscopy room, the level of formaldehyde identified (100 ppbv) was above the international limits established to non-industrial internal places. The ratios of the mixture of indoor and outdoor places, I/O, indicate the biggest presence of carbonyl compounds in internal places. Acrolein has been identified (6.4 to 9.3 ppbv) at indoor places. At the external area, there where found similar values (6,4 to 6,8 ppbv), and the ratio I/O obtained is near to 1. The origin of these compounds is possibly construction materials, smoke of cigarettes, adhesives, metabolism of microorganisms or they may have come from the outdoor to the indoor

Les composés organiques volatiles (COVs) sont les polluants organiques atmosphériques les plus abondants. Parmi les différentes solutions pour combattre cette pollution, l'utilisation d'adsorbants moléculaires tels que les zéolithes semble être efficace. Cependant les synthèses classiques de zéolithes aboutissent généralement à des tailles de cristaux de l'ordre de plusieurs dizaines de micromètres. Les capacités et les cinétiques de piégeage, sensibles aux phénomènes de diffusion et de surface pourraient potentiellement être améliorées par l'utilisation de nanocristaux ou de produits zéolithiques hiérarchisés (micro/mésoporeux). Dans ce travail de thèse, nous avons synthétisé des zéolithes aluminosiliciques ou purement siliciques de type structural FAU, MFI et *BEA. Ces dernières sont synthétisées avec différentes morphologies et tailles de particules telles que les nanocristaux et les zéolithes hiérarchisées (nanofeuillets et/ou nanoéponges en utilisant des agents structurants bifonctionnels). Ces matériaux sont comparés aux zéolithes conventionnelles, afin d'étudier l'influence de la morphologie sur la cinétique et la capacité de piégeage de COVs. Les caractéristiques structurales et texturales des zéolithes synthétisées ont été étudiées par ORX, MEB, manométrie d'adsorption/désorption de diazote, ATG-ATD, RMN du solide. Enfin, la capacité d'adsorption d'une molécule modèle, le n-hexane, au sein de ces zéolithes a été étudiée par thermogravimétrie. Dans le cas des zéolithes de type MFI et *BEA, les zéolithes hiérarchisées ont montré une augmentation de la capacité de piégeage en n-hexane par rapport aux zéolithes conventionnelles. La capacité de piégeage en n-hexane a été multipliée par 7 dans le cas des nanoéponges de type *BEA et par 6 dans le cas des nanocristaux de type *BEA comparés aux microcristaux de type *BEA (693 mg/g vs 103 mg/g et 591 mg/g vs 103 mg/g, respectivement). / Volatile organic compounds (VOCs) are the most abundant organic pollutants. Among the various solutions to fight against this pollution, the use of molecular adsorbents appears as a potential alternative for the control of contamination. The porous materials have many advantages due to their low cost, their physical characteristics and their useful properties related to their structure and their large surface area. However, conventional synthesis of zeolites generally lead to micrometer size crystals. The capacity and the kinetics of adsorption that are sensitive to the diffusion and the surface phenomena could be potentially improved by the use of zeolite nanocrystals or hierarchical products (micro / mesoporous). These nanomaterials have high potential due to their small size and their exalted outer surface that promote access of pollutants and improve the adsorption capacity. ln the thesis work, we synthesized zeolites with different structural types such as FAU, MFI and *BEA. Each structure type was synthesized in different morphologies such as nanosponges and /or nanosheets using a bifunctional structuring agent, as well as nanocrystals by the clear solution method. These materials were compared with conventional micrometer-sized zeolites. The purity and the porous texture have been characterized by using XRD, SEM, nitrogen adsorption/desorption techniques, TGA-DTA and solid state NMR. Finally, the adsorption capacity of a model molecule, the n-hexane, in these zeolites have been studied by thermogravimetry. In the case of *BEA and MFI-type zeol ites, the hierarchical zeolites showed an increase of the adsorption capacity of n-hexane compared to conventional zeolites. The adsorption capacity of n-hexane was multiplied by 7 in the case of *BEA-type nanosponges and by 6 in the case of the *BEA-type nanocrystals compared to *BEA_type microcrystals (693 mg / g vs 103 mg / g and 591 mg / g vs 103 mg / g, respectively).

Como em qualquer outra organização, as empresas de engenharia química vêm cada vez mais utilizando ferramentas de Tomadas de Decisão para escolhas de soluções técnicas para projetos, operações, desenvolvimento, dentre tantas. A tomada de decisão é o processo de responder a um problema, utilizando um conjunto de técnicas qualitativas e quantitativas para selecionar a solução ou ação, dentre várias alternativas que seja mais adequada para a resolução daquele problema. Dentre estas ferramentas, as mais utilizadas são a MAUT, do inglês Multiattribute Utility Theory (Teoria de Utilidade Multiatributos) e a AHP, do inglês Analytic Hierarchy Process (Processo de Análise Hierárquica).Neste trabalho, estes dois métodos são aplicados num mesmo problema de engenharia química: a seleção de um sistema para tratamento de compostos orgânicos voláteis durante o carregamento de navios que transportam petróleo e derivados. Para isto é realizada, em primeiro lugar, a descrição detalhada de cada método, a conceituação de composto orgânico volátil, a legislação pertinente e a descrição de cada alternativa como solução para controle deste tipo de emissão. Os resultados apontados pelos métodos MAUT e AHP são então comparados a fim de verificar se ambos conduzem a mesma solução. Pretende-se também observar o grau de influencia das diferentes áreas de atuação de uma organização na escolha final da tomada de decisão e verificar as percepções dos profissionais sobre cada método aplicado. Percebeu-se, entretanto, que as metodologias não conduziram, neste trabalho, a soluções idênticas, devido à influência das características de cada método, e que profissionais de uma mesma área de atuação tendem a tomarem o mesmo tipo de decisão

Como em qualquer outra organização, as empresas de engenharia química vêm cada vez mais utilizando ferramentas de Tomadas de Decisão para escolhas de soluções técnicas para projetos, operações, desenvolvimento, dentre tantas. A tomada de decisão é o processo de responder a um problema, utilizando um conjunto de técnicas qualitativas e quantitativas para selecionar a solução ou ação, dentre várias alternativas que seja mais adequada para a resolução daquele problema. Dentre estas ferramentas, as mais utilizadas são a MAUT, do inglês Multiattribute Utility Theory (Teoria de Utilidade Multiatributos) e a AHP, do inglês Analytic Hierarchy Process (Processo de Análise Hierárquica).Neste trabalho, estes dois métodos são aplicados num mesmo problema de engenharia química: a seleção de um sistema para tratamento de compostos orgânicos voláteis durante o carregamento de navios que transportam petróleo e derivados. Para isto é realizada, em primeiro lugar, a descrição detalhada de cada método, a conceituação de composto orgânico volátil, a legislação pertinente e a descrição de cada alternativa como solução para controle deste tipo de emissão. Os resultados apontados pelos métodos MAUT e AHP são então comparados a fim de verificar se ambos conduzem a mesma solução. Pretende-se também observar o grau de influencia das diferentes áreas de atuação de uma organização na escolha final da tomada de decisão e verificar as percepções dos profissionais sobre cada método aplicado. Percebeu-se, entretanto, que as metodologias não conduziram, neste trabalho, a soluções idênticas, devido à influência das características de cada método, e que profissionais de uma mesma área de atuação tendem a tomarem o mesmo tipo de decisão

A quantificação de 11 compostos carbonílicos (formaldeído, acetaldeído, acetona, acroleína, propionaldeído, crotonaldeído, butiraldeído, benzaldeído, isovaleraldeído, valeraldeído e 2,5-dimetilbenzaldeído) e a identificação de outros 43 compostos orgânicos voláteis (alcanos, alcenos, aromáticos, halogenados e nitrogenados) foram feitas em 9 ambientes diferentes de trabalho localizados em áreas internas do Hospital Universitário, USP, São Paulo. Dentre os compostos carbonílicos, os mais abundantes em ordem decrescente foram formaldeído, acetona, acetaldeído e acroleína. As maiores razões de mistura de formaldeído foram observadas nas salas de Macroscopia (169,9 e 90,2 ppbv) e Técnicas Histológicas (11,7 e 58,7 ppbv), em decorrência da atividade desenvolvida nos locais. Na sala de Macroscopia, os níveis de formaldeído encontrados foram acima do limite (100 ppbv) estabelecido por órgãos internacionais que controlam a qualidade do ar em ambientes internos não industriais. As razões de mistura entre o ambiente interno e o ambiente externo, razões I/E, permitiram indicar a predominância dos compostos carbonílicos nos ambientes internos. A acroleína foi encontrada na faixa de 6,4 a 9,3 ppbv nos ambientes internos estudados. Na área externa, entretanto, foram encontrados valores similares (6,4 e 6,8 ppbv) aos dos ambientes internos obtendo razões I/E próximas de 1. Os compostos podem ter sido emitidos por materiais de construção e acabamento, fumaça do tabaco, adesivos, via metabolismo microbiano e bacteriano ou podem ter sido transportados por correntes de ar do ambiente externo para o ambiente interno / The quantification of 11 carbonyl compounds (formaldehyde, acetaldehyde, acrolein, acetone, propionaldehyde, crotonaldehyde, butiraldehyde, benzaldehyde, isovaleraldehyde, valeraldehyde and 2,5-dimethylbenzaldehyde) and the identification of another 43 volatile organic compounds (alkanes, alkenes, aromatic, halogenated and nitrogenated compounds) have been done with samples of 9 different indoor places inside the University Hospital at USP in São Paulo. Among the carbonyl compounds, there where found higher quantities of formaldehyde, acetone, acetaldehyde and acrolein in this order. The highest ratios of formaldehyde mixture have been observed at the Macroscopic room (169.88 and 90.2 ppbv) and Histological Techniques (11.7 and 58.7 ppbv), due to the routine activities of these places. At the Macroscopy room, the level of formaldehyde identified (100 ppbv) was above the international limits established to non-industrial internal places. The ratios of the mixture of indoor and outdoor places, I/O, indicate the biggest presence of carbonyl compounds in internal places. Acrolein has been identified (6.4 to 9.3 ppbv) at indoor places. At the external area, there where found similar values (6,4 to 6,8 ppbv), and the ratio I/O obtained is near to 1. The origin of these compounds is possibly construction materials, smoke of cigarettes, adhesives, metabolism of microorganisms or they may have come from the outdoor to the indoor

Abstract The work in this thesis concentrates on finding more active and durable catalysts for the demanding environmental application of the oxidation of sulfur-containing volatile organic compounds (S-VOCs). This application is challenging due to the high purification levels required and the catalyst deactivating nature of sulfur. In this thesis, dimethyldisulfide (DMDS) was used as the model molecule to represent S-VOCs since it is often present in odorous emissions and it is more difficult to treat than most of the other S-VOCs. It was found that the addition of a very small amount of Pt (0.3%) especially improves the selectivity of copper oxide based catalysts towards complete oxidation products ((carbon dioixide (CO2), water (H2O) and sulfur dioxide (SO2)) in DMDS oxidation. Catalyst characterization by transmission electron microscopy, temperature programmed reduction and X-ray photoelectron spectroscopy analyses suggests that this promoting effect is most likely due to the close interaction between Cu and Pt species on the bimetallic PtCu/γ-Al2O3 catalyst. The drawback of using the Al2O3 support is that it is not resistant towards sulfur poisoning. The deactivation of the self-made catalysts was studied with the help of an accelerated ageing procedure that was developed based on the information from the industrially aged volatile organic compound (VOC) catalysts. Industrial deactivation was caused by the sintering of the support and active metals and by the formation of metal sulfates with the support. After accelerated ageing, the silica doped alumina (Al2O3)0.8(SiO2)0.2 supported catalyst, showed remarkably promising results in terms of stability towards sulfur poisoning and the activity in DMDS oxidation was very close to that of the most active PtCu/Al2O3. The addition of less than 20% of SiO2 on the Al2O3 support led to a catalyst that is more selective and resistant to sulfur poisoning. / Tiivistelmä Väitöskirjassa tuotetaan uutta tietoa rikkipitoisten orgaanisten yhdisteiden (S-VOC) hapetukseen soveltuvien uusien katalyyttisten materiaalien synteesistä ja karakterisoinnista. S-VOC-yhdisteiden käsittely on vaativa katalyyttisen polton sovellus, koska näiden päästöjen käsittely edellyttää korkeaa puhdistustehoa, ja lisäksi yhdisteiden sisältämä rikki on katalyyttimyrkky. Tässä väitöskirjassa valittiin S-VOC-yhdisteitä edustavaksi malliaineeksi dimetyylisulfidi (DMDS), koska se on usein mukana käsiteltävissä S-VOC-päästöissä ja sen käsittely on vaativampaa kuin useiden muiden S-VOC-yhdisteiden käsittely. Tutkimustulosten mukaan hyvin pieni Pt-lisäys (0.3 %) parantaa erityisesti kuparioksidikatalyyttien selektiivisyyttä DMDS:n kokonaishapetustuotteiksi (CO2, H2O, SO2). Katalyyttien karakterisoinnin (läpäisyelektronimikroskopia, lämpötilaohjattu pelkistysreaktio, röntgensädefotoelektronispektroskopia) perusteella voidaan esittää parannuksen syyksi kuparin ja platinan läheinen kontakti bimetallisen PtCu/γ-Al2O3-katalyytin pinnalla. Al2O3-tukiaineen heikkoutena on sen deaktivoitumisherkkyys rikkiyhdisteiden läsnä ollessa. Väitöskirjatyössä valmistettujen katalyyttien deaktivitumista tutkittiin laboratoriomittakaavassa nopeutettujen ikäytyskokeiden avulla, jotka kehitettiin teollisessa käytössä deaktivoituneen katalyytin karakterisointien avulla saadun tiedon perusteella. Teollisessa käytössä olleen katalyytin deaktivoitumisen syyksi havaittiin tukiaineen ja aktiivisten metallien sintrautuminen sekä metallisulfidien muodostuminen tukiaineen kanssa. Nopeutettujen ikäytyskokeiden tulosten perusteella havaittiin, että piidioksidin lisäys alumiinioksiditukiaineeseen paransi tukiaineen rikin kestoa merkittävästi. Tutkimuksissa havaittiin myös, että piidioksidilla muokatun katalyytin aktiivisuus oli hyvin lähellä vastaavaa PtCu/γ-Al2O3-katalyytin aktiivisuutta. DMDS:n hapetuksessa selektiivisempi ja stabiilimpi katalyytti voidaan aikaansaada alle 20 %:n SiO2-lisäyksellä Al2O3-tukiaineeseen.

Ce manuscrit s’intéresse à une filière globale et durable de dépollution des eaux souterraines. Le polluant cible, le tétrachloroéthylène, est un composé organique volatil. La première étape de cette filière est la séparation du contaminant de l’eau. Elle a été réalisée par adsorption sur charbons actifs dans une colonne en lit fixe. Les résultats obtenus en laboratoire sur les capacités et les cinétiques d’adsorption ont permis de montrer l’efficacité de ce procédé. Un modèle issu de ces expériences a représenté correctement des conditions opératoires variées correspondant à celles utilisées dans l’industrie. Ce modèle a été validé par un pilote préindustriel installé sur site et fonctionnant en conditions réelles. La gestion des charbons actifs chargés en polluant a été étudiée. La régénération thermique a été privilégiée. Cette opération présente l’intérêt de rétablir les capacités d’adsorption des carbones activés et de récupérer les polluants en phase liquide. Bien que préférable à la production d’adsorbants, elle pourrait encore être plus durable et compétitive économiquement en effectuant le traitement thermique par voie solaire. Il a été montré que le taux de régénération est le même pour les régénérations solaire et classique. Il est donc possible, dans le cas du tétrachloroéthylène, de remplacer une source d’énergie fossile par le soleil. La solution de distillat obtenue lors de la régénération peut être minéralisée par photocatalyse hétérogène. Cette opération a été réalisée en laboratoire avec une lampe reproduisant le spectre solaire. La faisabilité de la photocatalyse solaire sur le résidu issu de cette filière de dépollution a ainsi été montrée. / This manuscript focuses on a comprehensive and durable treatment of polluted groundwater. The target contaminant, tetrachlorethylene, is a volatile organic compound. The first step in the treatment is the separation of contaminants. It was carried out by adsorption on activated carbons in a fixed bed column. The results obtained in the laboratory on the adsorption capacity and kinetics have shown the efficiency of this process. A mathematic model represented properly the various operating conditions corresponding to those used in the industry. This model has been validated by a pre-industrial pilot installed onsite and operating in real conditions. Management of spent activated carbons was studied. The thermal regeneration was chosen because it has the interest to restore the adsorption capacity of adsorbents and to collect the pollutants in a liquid phase. Although preferable to the production of activated carbons, it could still be economically more competitive and more sustainable by performing the heat treatment by solar means. It has been shown that the regeneration rate is the same for the solar and classical regenerations. It is therefore possible, in the case of tetrachlorethylene, to replace a fossil energy source by the sun.The distillate solution obtained during the regeneration can be mineralized by heterogeneous photocatalysis. This operation was carried out in the laboratory with a lamp reproducing the solar spectrum. The feasibility of solar photocatalysis on the final residue of the water treatment has been shown.

Diploma thesis deals with the assessment of volatile organic compounds contamination of selected working environment in Gumotex, joint stock company using passive sampling. The theoretical part contains description of these compounds and their reactions in the atmosphere, practical use of these substances and their effect on human health. The possibilities of passive sampling and determination of these substances are described as well. The experimental part contains analysis of volatile organic compounds at two selected workplaces in Gumotex, joint stock company using passive samplers Radiello. Final determination by gas chromatography with flame ionization detector was preceded by adsorption surface extraction of sampler with carbon disulfide. In conclusion, obtained data are compared with the permissible exposure limits and maximum allowable concentrations, which are defined by the National Health Institute.