The challenge for the future was defined by the Brundtland Commission (1987) and by the Rio Declaration (1992), in which the fundamental principles for achieving a sustainable development were provided. Sustainable chemistry can be defined as the contribution of chemistry to the implementation of the Rio Declaration. This thesis shows how Pressurized Fluid Extraction (PFE) can be utilized in chemical analysis, and how this correlates to Green Chemistry. The reliability and efficiency of the PFE technique was investigated for a variety of analytes and matrices. Applications discussed include: the extraction of the antioxidant Irganox 1076 from linear low density polyethylene, mobile forms of phosphorus in lake sediment, chlorinated paraffins from source-separated household waste, general analytical method for pesticide residues in rape seed, total lipid content in cod muscle, and squalene in olive biomass. Improved or comparable extraction yields were achieved with reduced time and solvent consumption. The decrease in use of organic solvents was 50-90%, resulting in minimal volatile organic compounds emissions and less health-work problem. Due to higher extraction temperatures and more efficient extractions, the selection of solvent is not as important as at lower temperatures, which makes it possible to choose less costly, more environmentally and health beneficial solvents. In general, extraction times are reduced to minutes compared to several hours. As a result of the very short extraction times, the amount of co-extracted material is relatively low, resulting in fewer clean-up step and much shorter analysis time. Selective extractions could be obtained by varying the solvent or solvent mixture and/or using adsorbents. In this thesis, the PFE technique was compared to the twelve principles of Green Chemistry, and it was shown that it follows several of the principles, thus giving a major contribution to sustainable chemistry.

Main group polycations and transition metal clusters had traditionally been synthesized via high-temperature routes by performing reactions in melts or by CTR, at room-temperature or lower temperature by using so-called superacid solvents, and at room-temperature in benzene–GaX3 media. Considering the major problems associated with higher temperature routes (e.g. long annealing time, risk of product decomposition, and low yield) and taking into account the toxicity of benzene and liquid SO2 in room-temperature or lower temperature synthesis, a soft and sustainable chemical approach has been developed, employing a Lewis-acidic IL [bmim]Cl/AlCl3. This new alternative reaction medium has proven to be an excellent solvent system for the single–step synthesis of main group polycations and transition metal clusters. X-ray diffraction and Raman spectroscopy have been used for the structural characterization of the isolated compounds. Physical properties and quantum chemical calculations of some of the compounds have also been carried out.

Environmentally benign alternatives for solvents and catalysts are essential for the development of sustainable chemical processes. Toward this end, we focused our research on the design of novel solvents and catalysts that reduce the environmental impact of these important materials. In this research, we develop switchable and tunable systems that couple reaction and separation to ease the processing requirements for product isolation and catalyst recovery. The switchable solvents use a ¡°switch¡± to transition from non-volatile, polar, aprotic solvents to volatile gases that can be easily separated. This allows us to facilitate reactions within the solvent and then enable easy separation through activation of the switch. We have used these materials for numerous reaction applications, including difficult reactions involving highly immiscible compounds. We also extended the work to acid-catalyzed reactions, in which we can avoid wasteful neutralization processes that are often associated with homogeneous acid catalysis. The tunable solvents use carbon dioxide pressure to ¡°tune¡± into desired solvent properties. We enable this through the dissolution of carbon dioxide into organic solvents, which generates gas-expanded liquids with solvent properties highly dependent on the carbon dioxide pressure. We can use this effect to couple homogeneous reaction with heterogeneous separation, allowing for recovery of expensive catalysts and ligands. In this work, we assess the possibilities of using liquid polyethylene glycol in the tunable systems, studying the phase behavior and industrial applications.

Laccase (benzenediol:oxygen oxidoreductase, EC 1.10.3.2), a multi-copper-containing oxidoreductase enzyme, is able to catalyze the oxidation of various low-molecular weight compounds, specifically, phenols and anilines. Due to their high stability, selectivity for phenolic substructures, and mild reaction conditions, laccases are attractive for fine chemical synthesis. In this study, new green domino syntheses were developed by conducting the reaction in an aqueous medium, an environmentally-friendly solvent, and using laccase as a biocatalyst. The first study presents a work on the synthesis of naphthoquinones in the aqueous medium. Herein, laccase was used to oxidize o- and p-benzenediols to generate o- and p-benzoquinones in situ. These quinones then underwent Diels-Alder and oxidation reactions to finally generate napthoquinone products. This reaction system can yield naphthoquinones in up to 80% yield. The next part of this thesis reports the cascade synthesis of benzofuran derivatives from the reaction of catechols and 1,3-dicarbonyl compounds via oxidation-Michael addition in the presence of laccase and Sc(OTf)3/SDS in an aqueous medium. Depending on the substrates, one-pot yields of benzofurans averaged 50-79%. From an environmental concern, this system still produced a hazardous waste from the transition metal catalyst. Therefore, the development of alternative methodologies to replace the lanthanide metal catalyst in this synthesis is a high priority to enhance the overall green chemistry aspect. As a consequence, lipase was used as a catalyst to replace Sc(OTf)3 for the synthesis of benzofuran derivatives. In addition, this catalytic system was also used to catalyze the reaction of anilines and catechol. In the last part of this thesis, laccase was applied to the modification of high-lignin softwood kraft pulp. This modification demonstrates the potential of laccase-facilitated grafting of amino acids to high lignin content pulps to improve their physical properties in paper products which resulted from the increase of carboxylic acid group of the fibers. In this study, a variety of amino acids were examined. Laccase-histidine treatment provided the best yield of acid groups on pulp fiber and was used in the preparation of handsheets for physical strength testing. Laccase-histidine-treated pulp showed an increase in the strength properties of the resulting paper.

Σκοπός της εργασίας αυτής είναι η ανάλυση του νέου νομικού καθεστώτος διαχείρισης και ελέγχου των χημικών ουσιών σε ευρωπαϊκό επίπεδο και η ανάδειξη των ποικίλων διακυβευμάτων που αυτό θέτει. Το νέο αυτό νομικό καθεστώς, παρά την μακροχρόνια διαβούλευση του, δεν είναι τελικά απαλλαγμένο από αδυναμίες και προβλήματα εφαρμογής. Πρόκειται για τον νέο κανονισμό REACH (αρχικά του Registration, Evaluation and Authorisation of Chemicals) ή κανονισμό 1907/2006/ΕΚ. Ο κανονισμός REACH αποτελεί ένα ενιαίο ευρωπαϊκό νομοθέτημα για την καταχώριση, την αξιολόγηση, την αδειοδότηση και τους περιορισμούς των χημικών ουσιών, αντικαθιστώντας 40 διαφορετικά υφιστάμενα νομοθετικά μέτρα. Η εργασία χωρίζεται στην εισαγωγή, σε έξι κεφάλαια και τέλος τα συμπεράσματα. Στην εισαγωγή παρουσιάζεται η υφιστάμενη νομοθεσία της ευρωπαϊκής ένωσης για τις χημικές ουσίες, τα προβλήματα από την εφαρμογή της καθώς και η ανάγκη για ένα νέο νομοθετικό πλαίσιο το οποίο θα αντικαταστήσει το υφιστάμενο και θα έχει ως πρωταρχικό σκοπό την προστασία της ανθρώπινης υγείας και του περιβάλλοντος. Αναφορά γίνεται στην βιώσιμη ανάπτυξη και την πράσινη χημεία, καθώς αποτελούν βασικούς πυλώνες του κανονισμού. Επίσης παρουσιάζονται οι βασικές αρχές του κανονισμού (αρχή της προφύλαξης, της υποκατάστασης κλπ) καθώς και οι επιδιωκόμενοι στόχοι από την εφαρμογή του. Στο πρώτο κεφάλαιο γίνεται μια αναλυτική παρουσίαση της αρχής της προφύλαξης, η οποία αποτελεί βασική και θεμελιώδης αρχή του κανονισμού. Γίνεται αναφορά στην σχέση της με την αρχή της πρόληψης, στην πορεία της μέσα στο ευρωπαϊκό δίκαιο και στη διατροφική πολιτική της ευρωπαϊκής ένωσης καθώς και η αντιμετώπισή της από το ελληνικό δικαιικό σύστημα. Στο δεύτερο κεφάλαιο παρουσιάζεται αναλυτικά η οικοδόμηση του κανονισμού REACH, μέσω των σημαντικότερων χρονολογικών γεγονότων που άλλοτε ενίσχυσαν και άλλοτε αποδυνάμωσαν το κανονισμό, ικανοποιώντας κάθε φορά και διαφορετικά συμφέροντα ή απαιτήσεις, έως την οριστικοποίηση του τελικού του κειμένου. Ειδική αναφορά γίνεται στο ρόλο του Παγκόσμιου Οργανισμού Εμπορίου για τη διαμόρφωση του τελικού κειμένου του κανονισμού. Στη συνέχεια, στο τρίτο κεφάλαιο, παρουσιάζονται αναλυτικά το πεδίο εφαρμογής του κανονισμού, τα θεσμικά όργανα και οι αρμοδιότητές τους καθώς και οι βασικές διατάξεις του κανονισμού, η καταχώριση, η αξιολόγηση, η αδειοδότηση και περιορισμοί των χημικών ουσιών. Ακολουθεί το τέταρτο κεφάλαιο, όπου παρουσιάζεται ο κανονισμός CLP (αρχικά του Classification, Labelling, Packaging) για την ταξινόμηση, την επισήμανση και συσκευασία χημικών ουσιών και μειγμάτων ή κανονισμός 1272/2008/EK. Ο κανονισμός CLP συμπληρώνει και τροποποιεί τον κανονισμό REACH στο κενό που παρουσιάζει όσον αφορά την ταξινόμηση, την σήμανση και τη συσκευασία των χημικών ουσιών και τον εναρμονίζει με το Παγκόσμιο Εναρμονισμένο Σύστημα ταξινόμησης και επισήμανσης για τις χημικές ουσίες και τα μείγματα των Ηνωμένων Εθνών. Στο πέμπτο κεφάλαιο γίνεται μια αναλυτική αποτίμηση του κανονισμού REACH, καθώς παρουσιάζονται και αναλύονται τόσο οι θετικές του όψεις όσο και οι αδυναμίες του. Αναλυτική αναφορά γίνεται στο κόστος εφαρμογής του κανονισμού καθώς και στα οικονομικά οφέλη που προκύπτουν από την εφαρμογή του. Επίσης παρουσιάζοντα τα προβλήματα ερμηνείας και εφαρμογής του κανονισμού. Ακολουθεί το έκτο κεφάλαιο, στο οποίο γίνεται αναφορά στην εφαρμογή του κανονισμού REACH στην Ελλάδα καθώς παρουσιάζεται η υπεύθυνη αρμόδια αρχή για την εφαρμογή του κανονισμού και ο ρόλος της, το πεδίο εφαρμογής του κανονισμού (επιχειρήσεις χημικών προϊόντων) καθώς και ο ρόλος του Συνδέσμου Ελληνικών Χημικών Βιομηχανιών. Τέλος στα συμπεράσματα γίνεται μια συγκεντρωτική παρουσίαση και σύγκριση των αρνητικών και θετικών χαρακτηριστικών του κανονισμού και αποτιμάται ο βαθμός της επίτευξης των αρχικών στόχων του μέσα στο χρονικό διάστημα από την ημερομηνία εφαρμογής του έως σήμερα. Επίσης παρουσιάζεται πως ο κανονισμός REACH αποτελεί καινοτόμο νομοθετικό εργαλείο στα χέρια της διοίκησης αν και αποδυναμωμένος σε σχέση με το αρχικό του κείμενο και την αρχική πεποίθηση για ολοκληρωμένη και υψηλού επιπέδου προστασία της ανθρώπινης υγείας και του περιβάλλοντος. / Aim of this work is the analysis of new legal regime of management and control of chemical substances in European level and the emergence of diverse implications that this poses. This new legal regime, despite its long-lasting consultation, is not finally exempted from weaknesses and problems of application. This is the new REACH Regulation (initials of the Registration, Evaluation and Authorisation of Chemicals) or regulation 1907/2006/EC. REACH is a uniform European legislation on the registration, evaluation, authorisation and restriction of chemicals, replacing 40 different existing legislative measures. The work is divided into the introduction, six chapters and finally conclusions. The introduction presents the existing EU legislation on chemicals, the problems of implementation as well as the need for a new legal framework which will replace the existing and will have as fundamental aim the protection of human health and environment. Reference is made to sustainable development and green chemistry, which are key pillars of the regulation. It also presents the basic principles of the regulation (precautionary principle, substitution principle, etc) as well as the objectives pursued by its application. In the first chapter becomes an analytic presentation of precaution principle, which constitutes basic and fundamental principle of regulation. Reference is made in relation to the prevention principle, in European law and food policy in the European Union as well as its confrontation from Greek law system. In the second chapter is presented in detail the construction of REACH regulation, by means of the most important chronological facts that sometimes reinforced and sometimes watered down regulation, satisfying each time and different interests or requirements, until the finalization of the final text. Special reference to the role of the World Trade Organization is made for the configuration of final text of regulation. Afterwards, in the third chapter, are presented in detail the field of application of regulation, the institutional bodies and their competences as well as the basic provisions of regulation, the registration, evaluation, authorisation and restriction of chemicals. Fourth chapter follows, where regulation CLP is presented (initials of the Classification, Labeling and Packaging) for the classification, labeling and packaging of substances and mixtures or regulation 1272/2008/EC. Regulation CLP supplements and modifies regulation REACH in the void that it presents with regard to the classification, labeling and packing of chemical substances and it harmonizes REACH with the World Harmonized System of classification and labeling for the chemical substances and mixtures of United Nations. In the fifth chapter becomes an analytic assessment of regulation REACH, while are presented and analyzed both positive aspects and weaknesses. A detailed reference becomes in the cost of implementing the regulation and to the economic benefits arising from its application. Also the problems in the interpretation and application of the regulation are presented. Following the sixth chapter, in which reference is made in the implementation of reach in Greece as the responsible authority for the application of the regulation and its role, the field of application of regulation (enterprises of chemical products) as well as the role of the Association of Greek Chemical Industries. Finally, in the conclusions is a summary and comparison of negative and positive characteristics of regulation and evaluation of the extent of the initial objectives within the period from the date of application until now. It also shows that REACH is an innovative legislative tool in the hands of the administration, although weak compared to the initial text, and the initial conviction for integrated and high level of protection of human health and environment.

Made available in DSpace on 2016-06-02T20:37:48Z (GMT). No. of bitstreams: 1 5407.pdf: 1478791 bytes, checksum: 131adc16889c1ddfaa53704df84e9bfc (MD5) Previous issue date: 2013-06-21 / The present case study focused on the development, adaptation and analysis of the introduction of Green Chemistry in an experimental course in the first year of the chemistry teacher training Degree offered by the Chemistry Department of the Federal University of São Carlos (DQ-UFSCar), São Paulo State, Brazil. Modules for experimental lessons were proposed, based on the Science-Technology-Society (STS) teaching approach, and applied during one semester in a class of 30 undergraduate s (1st Semester 2011). The proposed didactic modules began with the presentation and discussion of documentaries with emphasis on controversial socioscientific issues, followed by an experiment of investigative character. All the conceptual topics included in these modules were originally part of the course syllabus, which were associated with the procedural and attitudinal contents emphasizing environmental and green chemistry education. The research corpus consisting of students textual production (response to questionnaires and reports) and transcript interviews (focal groups). The content analysis method was employed to describe and interpret the survey data. Also, the analysis of the experimental didactic modules using a holistic metric known as Green Star (GS) was carried out. Through the analysis of the results obtained by qualitative research in this case study, the didactic proposal enabled students to understand the contents in a complex context that included socioscientific issues, considering Green Chemistry as a mandatory demand for the initial teacher training. / O presente estudo teve como objetivo principal o desenvolvimento, adaptação e análise da inserção de práticas de laboratório com ênfase à Química Verde em uma disciplina de caráter experimental do primeiro ano do curso de Licenciatura em Química do Departamento de Química da Universidade Federal de São Carlos (DQ-UFSCar). Módulos para aulas experimentais foram propostos, baseados na abordagem de ensino CTS, e aplicados no decorrer de um semestre junto uma turma de 30 licenciandos do curso de interesse (1o. Semestre de 2011). A proposta de ensino estudada iniciou-se com uma aula expositiva dialogada (apresentação e discussão de reportagens ou documentários com ênfase às problemáticas sociocientíficas controversas), seguida pela realização do experimento de caráter investigativo, que compreendia os conteúdos conceituais inicialmente contidos na ementa da disciplina, associados aos conteúdos procedimentais e atitudinais voltados às questões ambientais e da Química Verde. O corpus da pesquisa foi constituído pela produção textual discente (resposta aos questionários e relatórios) e transcrição de entrevistas. A análise de conteúdo foi a metodologia empregada para descrever e interpretar os dados da pesquisa. Também neste trabalho realizou-se uma análise do grau verde das experiências aplicadas, usando como instrumento uma métrica holística, a Estrela Verde (EV). Por meio da análise dos resultados obtidos pela pesquisa qualitativa pautada em um estudo de caso foi possível observar que as experiências executadas possibilitaram aos estudantes compreender os conteúdos abordados e considerar a Química Verde como um eixo a ser adotado no ensino da Química.

Neste trabalho, fracionou-se e tratou-se a argila Brasgel. Esta argila foi pilarizada em vários estágios de facionamento e/ou tratamento com 5 meq de Al / g de argila: (i) Al-PILC, a argila passou por todos os estágios de fracionamento e tratamento (ARG), (ii) Al-PILCFe, a argila não passou pela etapa de retirada de Fe livre (ARGFe) e (iii) Al-PILCFe/silte, a argila não passou pelas etapas de retirada de silte e Fe livre (ARGFE/silte). Em análise por DRX observou-se que as Al-PILCs apresentaram uma distância basal maior que as argilas de partida. A análise textural indicou que as argilas Al-PILCs e ARGs são materiais mesoporosos, com poros do tipo fenda estreita e do tipo fenda, respectivamente. Além disso, as Al-PILCs apresentaram área superficial razoavelmente maior que as ARGs correspondentes. Outras análises feitas nas argilas foram: teor de Si, Fe e Al; CTC; FTIR; TGA e TGD. As argilas Brasgel pilarizadas foram usadas como catalisador na reação de isomerização do óxido de estireno em hexano sob refluxo. A reação foi seletiva na formação de fenilacetaldeído. As argilas Al-PILCFe e Al-PILCFe/silte apresentaram melhor desempenho catalítico (100 % de conversão em 20 min de reação). Assim, as argilas Brasgel pilarizadas se apresentaram como uma Tecnologia Limpa na reação de isomerização do óxido de estireno ao fenilacetaldeído. Palavras-chave: Desenvolvimento Sustentável. Tecnologia Limpa. Química Verde. Argilas Pilarizadas. Isomerização de Epóxidos. / This work, the Brasgel clay was fractionated and treated. The clay was pillared in several stages of fractionation and / or treatment with Al 5 meq / g of clay: (i) Al- PILC, the clay has passed through all stages of treatment and fractionation (ARG), (ii) Al-PILCFe, the clay would not pass the step of removal of free Fe (ARGFe) and (iii) Al-PILCFe/silt, clay has not gone through the steps of removing silt and free Fe (ARGFE/silt). XRD analysis showed that the Al-PILCs showed a basal spacing greater than the starting clays. The textural analysis indicated that the Al-PILCs and ARGs are mesoporous materials, with pore narrow slit type and slit type, respectively. Moreover, the Al-PILCs showed reasonable surface area greater than the corresponding ARGs. Other analyzes were made on clays: the content of Si, Fe and Al; CEC, FTIR, TGA and TGD. Brasgel pillared clays have been used as catalyst in the isomerization reaction of the styrene oxide in refluxing. The reaction was selective for the formation of phenylacetaldehyde. Al-PILCFe and Al-PILCFe/silt clays showed better catalytic performance (100% conversion in 20 min of reaction). Thus, the pillared clays Brasgel presented as a Clean Technology in the isomerization reaction of styrene oxide to phenylacetaldehyde. Keywords: Sustainable Development. Clean Technology. Green Chemistry. Pillared Clays. Isomerization of Epoxides.

Magister Scientiae - MSc (Physics) / Zinc oxide (ZnO) is a wide and direct semiconductor with a wurtzite crystal structure. Its multifunctionality as the ideal candidate in applications such as blue-UV light emitting diodes, transparent conducting oxide, selective gas sensor and efficient catalyst support among others, has attracted a significant interest worldwide. Nano-scaled ZnO has been synthesized in a plethora of shapes. A rich variety of physical and chemical methodologies have been used in the synthesis of undoped or doped ZnO. However, such methods either necessitate relatively high vacuum infrastructures, elevated temperatures, or the use of toxic reagents. The "green chemistry" synthesis of metal oxide nanoparticles which is based on using natural plant extract as an effective 'reducing agent' of metal precursor, has been reported to be a cleaner and environment-friendly alternative to the physical and chemical methods. The thesis is based on the synthesis and the main physical properties of pure ZnO nanoparticles synthesized by a completely green chemistry process using the natural extract of Aspalathus Linearis to bio-reduce the zinc acetate precursor. The obtained ZnO nanopowdered samples were annealed at different temperatures from 300 °C to 600 °C. The samples were characterized using Scanning Electron Microscopy, Energy Dispersive Spectroscopy, Transmission Electron Microscopy, X-ray Diffraction, Differential Scanning Calorimetry, Thermogravimetric Analysis and Fourier Transform Infrared. Highly pure quasi-spherical ZnO nanoparticles with an average crystallite size of 24.6 nm (at 300 °C), 27.2 nm (at 400 °C), 27.6 nm (at 500 °C), and 28.5 nm (at 600 °C) were found. The results also showed that the average crystallite size increased with an increase in annealing temperature. It was successfully demonstrated that the natural plant extract of Aspalathus Linearis can be used in the bio-reduction of zinc acetate dihydrate to prepare highly pure ZnO nanoparticles.

Les ressources minérales s’épuisent inexorablement, les minerais riches sont de plus en plus difficilement accessibles, et le traitement des minerais implique d’importants impacts environnementaux. En Nouvelle-Calédonie, l’extraction du nickel nécessite la destruction de l’horizon fertile supérieur des sols, et les mines se présentent comme des carrières à ciel ouvert, soumises à l’érosion et menaçant la biodiversité du territoire. Bien que l’exploitation du nickel soit au cœur de l’économie locale, la réhabilitation écologique des sites miniers, et la réintroduction durable d’un couvert végétal sont une nécessité.Le laboratoire ChimEco a démontré qu’il était possible de revégétaliser les sites miniers en réintroduisant des espèces végétales pionnières, résistantes et accumulatrices de manganèse. Ces plantes accumulatrices sont capables d’extraire le manganèse naturellement présent dans le sol et de l’accumuler dans leurs parties aériennes : on parle de phytoextraction. Le laboratoire ChimEco propose en outre une valorisation scientifique et à terme économique des efforts de réhabilitation engagés sur le terrain. En effet, à partir de la biomasse riche en manganèse des plantes accumulatrices, le laboratoire ChimEco a développé un procédé innovant de recyclage des éléments métalliques d’origine végétale en catalyseurs polymétalliques pour la chimie. Il s’agit de l’Ecocatalyse. Ces écocatalyseurs riches en Mn, notés Eco-Mn, ont montré une activité catalytique intéressante dans plusieurs synthèses organiques.Les résultats obtenus en écologie et en chimie par le laboratoire ChimEco prouvent la nécessité d’étudier finement la structure des écocatalyseurs en les considérant comme des matériaux innovants, afin de comprendre et d’améliorer leur activité en synthèse organique, et d’exploiter au mieux les possibilités du procédé. C’est précisément dans ce contexte que s’inscrivent ces travaux de thèse.Plusieurs techniques d’analyse ont été utilisées. Les analyses ICP-MS ont permis de déterminer la composition élémentaire des Eco-Mn. La DRX a permis de mettre en évidence la présence de sels mixtes originaux tels que K3NaMnCl6 sous forme cristalline dans les Eco-Mn. Enfin l’absorption des rayons X a permis de déterminer la nature des espèces présentes dans les catalyseurs, ainsi que le degré d’oxydation du manganèse et du fer. En outre, l’étude du réarrangement d’un acétal cyclique, ainsi que le suivi de la désorption de la pyridine à la surface des Eco-Mn, ont été utilisés pour étudier les propriétés acides des écocatalyseurs. Ces analyses ont permis de répondre à deux objectifs précis : d’une part déterminer la nature des complexes qui composent les Eco-Mn, et d’autre part, mieux comprendre les propriétés physico-chimiques de ces catalyseurs, leur degré d’oxydation et leurs propriétés acides. Ces analyses ont également permis de mieux appréhender les deux étapes du procédé de synthèse des Eco-Mn. Enfin, des catalyseurs synthétiques et témoins ont également été produits et étudiés dans les mêmes conditions d’analyse que les Eco-Mn, dans le but de déterminer si les Eco-Mn ont une spécificité et une empreinte végétale. / Mineral resources are running out, ores are hardly accessible, and ores processing damage the environment. In New-Caledonia, nickel ores mining requires to remove all the upper layers of the ground, leading to open-cast mines subjected to erosion, which threaten the environment and the biodiversity of the archipelago. Although mining ores exploitation is important for the economy of New-Caledonia, the ecological remediation of mining areas through the restoration of a vegetation cover, are necessary.ChimEco laboratory has demonstrated that it is possible to reintroduce pioneering endemic plant species, which are resistant to climate conditions and accumulate manganese, to restore New-Caledonian mining sites. These accumulating plants extract Mn from the ground to their aerial parts: it is called phytoextraction. Besides, ChimEco laboratory puts forward a new scientific and economic valorisation of phytoremediation efforts in New-Caledonia. Indeed, an innovative process has been developed to recycle metallic elements from manganese enriched biomass into innovative and polymetallic catalysts for organic synthesis. This new process is called Ecocatalysis. Ecocatalysts enriched in manganese, Eco-Mn, have demonstrated interesting and promising catalytic activities in several reactions.Regarding the good results achieved by ChimEco in ecology and in chemistry with accumulating plants and resulting Eco-Mn, it is necessary to better and precisely characterise Eco-Mn catalysts, by considering them as innovative materials, in order to understand and foresee their catalytic activity. This PhD work belongs within this context.Several analyses have been performed to characterise Eco-Mn catalysts. First, ICP-MS enables to identify metallic composition of Eco-Mn. Besides, XRD analyses highlight the presence of complex crystallized manganese salts, like K3NaMnCl6. Finally, X-ray absorption spectroscopy enables us to study the nature of manganese species which compose Eco-Mn catalysts, and to understand the oxidation states of Mn and Fe. Moreover, acid properties of Eco-Mn were demonstrated thanks to the study of a cyclic acetal rearrangement and infra-red spectroscopy of adsorbed pyridine. All these analyses were performed in order to determine first the composition of Eco-Mn catalysts, and secondly to highlight their physico-chemical properties, their oxidation state and their acid properties. Furthermore, this study also enable us to better understand the different steps of the ecocatalysts production process. Finally, synthetic catalysts were also produced and analysed in the same conditions as Eco-Mn, in order to bring out the specificities of Eco-Mn.

Disponibiliza??o do conte?do parcial, conforme Termo de Autoriza??o no trabalho. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2016-12-21T19:05:57Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) wbiratan_cesar_macedo_oliveira_parcial.pdf: 128173 bytes, checksum: 9c9067430cf3b7ef9b7952182484b258 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-01-31T14:19:01Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) wbiratan_cesar_macedo_oliveira_parcial.pdf: 128173 bytes, checksum: 9c9067430cf3b7ef9b7952182484b258 (MD5) / Made available in DSpace on 2017-01-31T14:19:01Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) wbiratan_cesar_macedo_oliveira_parcial.pdf: 128173 bytes, checksum: 9c9067430cf3b7ef9b7952182484b258 (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Neste trabalho foi estudado o comportamento de extra??o do lant?nio em sistemas aquosos bif?sicos (SAB) e foi desenvolvido um novo m?todo hidrometal?rgico ambientalmente seguro para a extra??o seletiva de La a partir de lixiviado de baterias NiMH. O comportamento de extra??o do La foi avaliado verificando a influ?ncia dos seguintes par?metros: presen?a e concentra??o de diversos agentes extratantes (Alaranjado de xilenol, 1-(2-piridilazo)-2-naftol, Ditizona, 8-hidroxiquinolina, e 1,10-fenantrolina); pH (3,00, 6,00 e 9,00); eletr?lito (Li2SO4, Na2SO4, MgSO4, Na2C4H4O6 e Na3C6H5O7 ) e pol?mero (L64 e PEO1500) formadores do sistema. A efici?ncia de recupera??o foi avaliada atrav?s da an?lise da porcentagem de extra??o (% E) e as melhores condi??es de extra??o do analito foram obtidas no SAB formado por PEO1500 + Li2SO4 + H2O, pH = 6,00; empregando o extratante 1,10-fenantrolina, atingindo um valor m?ximo de %E = 74,1 %. Na sequencia o m?todo foi aplicado a um lixiviado de bateria NiMH. Os terras raras foram precipitados mediante ajuste de pH (2,50) e posteriormente solubilizado em solu??o de H2SO4 0,1 M. Ap?s 3 etapas sucessivas de extra??o foram obtidos altos valores de fator de separa??o (S) entre o analito e os concomitantes met?licos (SLa,Co = 6.3 x 103, SLa,Ni= 2,55 x 104, SLa,Fe= 1,15 x 103 and SLa,Ce= 30,9). Al?m disso, foi realizado um ensaio de stripping no qual 88,5% de La, em uma ?nica etapa, foi redisponibilizado sob a forma i?nica na FI para uma poss?vel etapa posterior de eletrodeposi??o. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / In this work was investigated the extraction behavior of lanthanum in the aqueous two-phase system (ATPS) and new environmentally safe hydrometallurgical method was developed for the selective extraction of La from NiMH battery leachate. The extraction behavior of La was evaluated verifying the influence of the following parameters on the metals extraction: presence and concentration of the several extractants 1-(2-piridil-azo)-2-naphtol, dithizone, 8-hydroxyquinoline, 1-10 phenanthroline and xylenol oragne; pH (3.00, 6.00 and 9.0); ATPS-forming electrolyte ((Li2SO4, Na2SO4, MgSO4, Na2C4H4O6 e Na3C6H5O7); ATPS-forming polymer (L64 or PEO1500). The recovery efficiency was evaluated through analyzing the extraction percentage (%E) and the best conditions for analyte extraction were achieved for the PEO1500 + Li2SO4 ATPS, pH = 6.00, using 1-10 phenanthroline as extractant agente (%E = 74,1 %). In the following section, the method was applied to a real NiMH battery leachate. The rare earths were precipitated by pH adjustment (2.50), which was solubilized in 0,1 M H2SO4 solution. After 3 steps of successive extractions it was possible to obtain high separation factor (S) values between the analyte and mettalic concomitant (SLa,Co = 6.3 x 103, SLa,Ni = 2,55 x 104, SLa,Fe = 1,15 x 103 and SLa,Ce = 30,9). Moreover, a stripping assay was carried out and after one single step, 88.5% of lanthanum was available to a possible electro winning step.