Дисертації з теми "Green sustainable chemistry"
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Stanley, Jessica. "Novel applications of catalysis for green and sustainable chemistry." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/12679.
Повний текст джерелаStanley, Jessica Nicole Gonzalo <1987>. "Novel applications of catalysis for green and sustainable chemistry." Doctoral thesis, Università Ca' Foscari Venezia, 2014. http://hdl.handle.net/10579/5655.
Повний текст джерелаMarus, Gregory Alan. "The application of green chemistry and engineering to novel sustainable solvents and processes." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/43755.
Повний текст джерелаCATERINA, RISI. "Studies on organic synthesis through sustainable catalysis." Doctoral thesis, Università di Siena, 2020. http://hdl.handle.net/11365/1094721.
Повний текст джерелаIn the first part of the PhD period, the use of the micellar catalysis was investigated, to perform reactions in water avoiding (or limiting) the use of the traditional organic solvents. The possibility to apply the micellar conditions for the hydrogen borrowing (HB) reaction to prepare amines was explored. Different Ru catalysts were screened using water as medium, under Microwave (MW) dielectric heating. Once optimized, the scope of the reaction was investigated using differently substituted amines and alcohols. Besides, the use of a biomass-derived solvent (GVL) was explored in Pd/C catalysed transformations to avoid the arching phenomena frequently observed using conventional solvents (e.g. toluene). A sustainable protocol for the synthesis of benzimidazoles employed different aliphatic and aromatic amines through a hydrogen transfer Pd/C. A heating profile and various studies of stability have been reported. A biocatalytic approach to pyridine and furans is also reported. These heterocycles are fundamental building blocks for the synthesis of pharmaceuticals, agrochemicals and organic material. Furthermore, these compounds are also employed in flavour and fragrance industry owing to their peculiar olfactory properties. Classical methodologies for their synthesis are based on low-yielding multistep methods, which involve the use of harsh conditions. Therefore, novel mild and greener methodologies for the preparation of heterocycles compounds are highly desirable. Aromatization of substituted 1,2,3,6-tetrahydropyridines (THPs) was performed using whole-cell monoamine oxidase MAO-N (variants from Aspergillus niger) catalyst. The aromatization of the tetrahydropyridine starting materials into the pyridine products was monitored through 1H NMR spectroscopy. During the optimization, different pyridine compounds are prepared to screen the best co-solvents and MAO-N variants. The kinetic profile of the biocatalytic transformation by MAO-N was also monitored via in situ 19F NMR experiments. Aromatization of different 2,5-dihydrofurans into corresponding furans was also performed using the Laccase/TEMPO catalytic system using mild conditions. A chemo- enzymatic cascade reaction starting directly from acyclic aliphatic precursor has been developed showing that metathesis Grubb's catalyst and the Laccase/TEMPO system can be used in combination for an efficient protocol.
CALASCIBETTA, ADIEL MAURO. "SUSTAINABLE SYNTHETIC METHODOLOGIES FOR THE PREPARATION OF ORGANIC SEMICONDUCTING MATERIALS: ORGANIC (OPTO)ELECTRONICS GROWING “GREEN”." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2021. http://hdl.handle.net/10281/312085.
Повний текст джерелаThe worldwide demand for energy-efficient and high-performing (opto)electronics, along with the increasing need for economically feasible and environmentally friendly chemistry, both require semiconducting materials that are both scalable and sustainable. The concern with waste generation and toxic/hazardous chemicals usage has already moulded many operations in chemical and manufacturing industries. To date, common syntheses to access organic semiconductors require the use of large quantities of toxic and/or flammable organic solvents, often involving reagents and by-products that are harmful to health and environment. Research in the field of organic electronics is now increasingly focusing on the development of new sustainable methodologies that allow to prepare active materials in a more efficiently way, caring further on safety and sustainability associated with production processes. The immediate approach applicable consist on the removal, or at least on the minimization, of harmful and toxic substances commonly employed within standard processes. The big elephant in the room in the synthesis of active materials is the amount of organic solvent employed, which could ideally be reduced by using aqueous solution of surfactants: in these nano/micro heterogeneous environments organic transformations can happen and often with unprecedent efficiency. Clearly, the process occur not through the dissolution of the reagents (starting materials and catalyst) but from their dispersion in water. Kwon as “micellar catalysis”, this strategy has proven to be highly effective on improving sustainability becoming a prominent topic in modern organic synthesis. In particular, the micellar catalysis strategy is compatible with the most common modern strategies employed for C-C and C-heteroatom bonds forming reactions and allow to perform reactions with high yields, in water and under very mild conditions. Nonetheless, the use of such method in the field of organic semiconductors is still limited, with only few relevant examples reported in literature concerning the preparation of π-conjugated molecular and polymeric materials. This Thesis describes the importance of introducing sustainability in the synthesis of organic semiconductors, satisfying several principles of the green chemistry guidance. Our research purpose is not to provide an exhaustive list of examples of such chemistry, but rather to identify a few key developments in the field that seem especially suited to large-scale synthesis. Then, the discussion will consider the synthetic approaches typically employed to access semiconducting materials with extended π-conjugated structures. In particular, the discussion will involve the well-known Pd-catalysed cross-coupling techniques. Finally, the topic of the work will focus on micro-heterogeneous environments as a new tool for introducing sustainability in the preparation of active materials in water, satisfying several criteria relevant to green chemistry. On my opinion, the micellar catalysis approach constitute today the more promising method to lower the overall cost and environmental impact in the production of organic semiconductors without affecting yields, purity, and device performance.
Downs, Emma. "An Investigation of Transition Metal Catalysts for Cyanohydrin Hydration: The Interface of Homogeneous and Heterogeneous Catalysis." Thesis, University of Oregon, 2014. http://hdl.handle.net/1794/18348.
Повний текст джерела2015-09-29
Hellman, Oskar. "Synthesis of framework porous sorbents using sustainable precursors." Thesis, Uppsala universitet, Nanoteknologi och funktionella material, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-445896.
Повний текст джерелаShearouse, William C. "Development and mechanistic understanding of ball milling as a sustainable alternative to traditional synthesis." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1353089340.
Повний текст джерелаFalco, Camillo. "Sustainable biomass-derived hydrothermal carbons for energy applications." Phd thesis, Universität Potsdam, 2012. http://opus.kobv.de/ubp/volltexte/2012/5978/.
Повний текст джерелаDie Notwendigkeit, die Abhängigkeit der Menschheit von fossilen Brennstoffen zu reduzieren ist die treibende Kraft hinter aktuellen Forschungsanstrengungen in den Materialwissenschaften. Folglich besteht heutzutage ein erhebliches Interesse daran Alternativen zu Materialien, die aus fossilen Resourcen gewonnen werden, zu finden. Kurzfristig ist zweifellos Biomasse die vielversprechendste Alternative, da sie aus heutiger Sicht die einzige nicht-fossile, nachhaltige und nachwachsende Kohlenstoffquelle ist. Konsequenterweise werden die Antrengungen neue Syntheseansätze zur Konvertierung von Biomasse und ihren Derivaten in kohlenstoffbasierten Materialien forwährend erhöht. In diesem Zusammenhang hat sich die Hydrothermalkarbonisierung (HTC) als sehr vielseitiges Werkzeug zur Konvertierung von Biomasse-basierten Ausgangsstoffen in funktionale Kohlenstoffmaterialien herausgestellt. Dennoch gibt es bisher wenige Ansätze um rohe Biomasse, genauer gesagt Lignicellulose, direkt in funktionale Materialien umzusetzen. Könnte der direkte Einsatz von roher Biomasse Verfahren wie der HTC zugänglich gemacht werden, würde dies die Nachhaltigkeit des Verfahrens immens steigern. Daher wurde in dieser Dissertation die Hydrothermalkarbonisierung von kohlenhydratreicher (d. h. Lignicelluse) und proteinreicher (d. h. Microalgae) Biomasse systematisch analysiert. Diese Untersuchung galt dem Ziel einen besseren Einblick in das Potential dieser thermochemischen Verarbeitungsmethode funktionale Kohlenstoffmaterialien aus unverarbeiteter Biomasse hervorzubringen zu gewinnen. Die hergestellten Materialien wurden mittels chemischer Aktivierung nachträglich weiter behandelt. Dieser zusätzliche Verarbeitungsschritt ermöglichte die Herstellung hochporöser aktiverter Kohlenstoffe (AC). Die aus Lignicellulose gewonnenen ACs zeigten exzellente Eigenschaften bei der Aufnahme von CO2 und der Hochdruckspeicherung von CH4 währen die aus Microalgae gewonnen Eigenschaften an den Tag legten (z. B. hohe Oberfläche und N-Dotierung), welche sie zu vielversprechenden Materialien für Superkondensatoren machen. Die in dieser Dissertation präsentierte Arbeit zeigte außergewöhnliche Fortschritte in Richtung der Anwendung von unbehandelter Biomasse als Ausgangsmaterial für die Produktion von funktionalen Kohlenstoffen.
Waldebäck, Monica. "Pressurized Fluid Extraction : A Sustainable Technique with Added Values." Doctoral thesis, Uppsala University, Department of Chemistry, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6022.
Повний текст джерелаThe 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.
RIGO, DAVIDE. "Sustainable processes for the chemical upgrading of renewables." Doctoral thesis, Università degli Studi di Trieste, 2022. http://hdl.handle.net/11368/3016991.
Повний текст джерелаThe present PhD thesis entitled Sustainable processes for the chemical upgrading of renewables has dealt with the design and implementation of both batch and continuous-flow methods for: i) the upgrading of biobased substrates including glycerol and its derivatives and 5-hydroxymethylfurfural (HMF); ii) the synthesis of cyclic organic carbonates via catalytic insertion of CO2 into terminal epoxides; iii) the preparation of polyesters from Kraft lignin (KL) with poly-anhydrides and polyisopropenyl esters as crosslinking agents. The first and part of the second year have been dedicated to the study of the reactivity of enol esters, particularly the nontoxic isopropenyl acetate (iPAc), with renawable 1,2-diols, glycerol and some of its derivatives. The design of original catalytic tandem protocols was developed, by which the above-mentioned reactants were converted into the corresponding acetates and acetal products with even 100% carbon efficiency. Based on these results, three papers were published on international peer-reviewed journals. Then, a period abroad at the University of Sydney under the supervision of Prof. T. Maschmeyer to start a cotutelle program for the achievement of the joint Italian-Australian PhD title was planned. However, due to the pandemic, the mobility was forbidden, and the related experimental work has been converted in a remote collaboration finalized at the writing of a review paper on the synthesis and reactivity of enol esters. Periodic videocalls have been organized with Prof. Maschmeyer during which the progress of the review article has been discussed. The resulting review paper entitled “Isopropenyl esters in green organic synthesis” and authored by D. Rigo, G. Fiorani, A. Masters, T. Maschmeyer, and M. Selva is currently almost finished, and its submission is expected by the end of this year. Parallelly, two new experimental studies were undertaken aimed to: a) the design of a protocol for the activation of CO2 in the insertion on terminal epoxides in the presence of a binary homogenous mixture of diethylene glycol and NaBr as catalyst/solvent; a) the upgrading of HMF through diversified approaches of transesterification, transcarbonation, reductive amination, aldol condensation, and vinylation reactions using safe reagents and solvents as iPAc, dimethyl carbonate, water, and ad-hoc prepared ionic liquids. Based on these results, two papers were published on international peer-reviewed journals. From March to September 2021 (6.5 months) an exchange research period at Stockholm University under the supervision of Prof. Joseph Samec has been undertaken. The activity was focused on the synthesis of lignin-based thermosetting polyesters. A scalable, ecofriendly, and solvent-free protocol for the preparation of the desired materials using a mixture of polyanhydrides and poly-isopropenyl esters as crosslinking agents of Kraft lignin (KL) has been implemented. Based on these results, a paper entitled “A new family of thermosets: Kraft lignin polyadipates” authored by D. Di Francesco, D. Rigo, K. R. Baddigam, A. Mathew, N. Hedin, M. Selva, J. S. M. Samec has been submitted to an international peer-reviewed journal and is currently on peer reviewing. In addition, the following book chapter M. Selva, G. Fiorani, D. Rigo “Supercritical Solvents” In Sustainable Organic Synthesis: Tools and Strategies, Chapter 10; A. Palmieri, S. Protti, Eds. RSC book, 2021 has been published.
Kassner, Michelle Kimberly. "Novel sustainable solvents for bioprocessing applications." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26683.
Повний текст джерелаCommittee Co-Chair: Eckert, Charles; Committee Co-Chair: Liotta, Charles; Committee Member: Bommarius, Andreas; Committee Member: Fernández, Facundo; Committee Member: Lu, Hang. Part of the SMARTech Electronic Thesis and Dissertation Collection.
Whitaker, Mariah R. "Design of Heterogeneous Catalysts Incorporating Solvent-Like Surface Functionality for Sustainable Chemical Production." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1563303994362428.
Повний текст джерелаBirgersson, Erica. "Chemical methods to increase the reactivity of lignin : In the context of green chemistry and education for sustainable development." Thesis, KTH, Skolan för teknikvetenskaplig kommunikation och lärande (ECE), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171044.
Повний текст джерелаForskning kring lignin i produkter har ökat under de senaste åren på grund av lignins fornyelsebarhet och tillganglighet i svartluten från massabruken. Idag används den största delen av sulfatligninet från svartluten som bränsle for att producera energi i sodapannan. Lignin fungerar som ett naturligt lim i växter och på grund av detta undersöks funktionen av kraftlignin som fenolersättning i trälim. Med anledning av ligninmolekylens låga reaktivitet behover lignin modifieras fore användning i produkter. Demetylering är en metod för att öka fenolhalten i lignin och skapa en högre reaktivitet. I denna studie utfördes Tiolmedierad och jodidmedierad demetylering. Det demetylerade ligninet utvärderades med avseende på forändringar i fenol-och hydroxylgrupper, molekylvikt, elementarsammansättning och andra egenskaper med hjälp av olika metoder,inklusive UV, SEC och 31 P NMR. Resultaten visade en minskning i fenolinnehall i motsats till den ökning som förväntades. Riktigt låga utbyten påvisades också vilket gör att resultaten inte är representativa. Storleksutvärdering visade att andelen med högt molekylviktsinnehåll i det demetylerade ligninproven hade ökat, vilket pekar mot förlust av lågmolekylära fraktioner. På grund av demetyleringen kan ligninet ha blivit mer hydrofilt och lösligt i DMF och vatten. Utöver detta kan bindningsklyvning ha skapat mindre fragment som också ökat lösligheten. Resultaten pekar mot förlust av mindre fragment i DMF-och vattenfaserna. De tillämpade demetyleringsmetoderna utvärderades med avseende på grön kemi. Produktion, avfall, kemikalier och effektivitet diskuterades och analyserades. De tillämpade demetyleringsmetoderna använder DMF som lösningsmedel, vilket inte är ett grönt alternativ. Grönare lösningsmedel såsom vatten, eller andra typer av energitillsättning, kan användas för att göra processen miljövänligare. Användandet av NaOMe i den thiolmedierade demethyleringen skapar metanol som en biprodukt vilket kan bytas ut mot vatten om NaOH istället används. Vidare studier behöver göras för att undersöka de båda baserna effektivitet. Naturvetenskapen har ett rykte om att vara hård och fast. Genom att föra in sociala frågor i den naturvetenskapliga utbildningen kan nya sätt att se på vetenskapen skapas. Ett samhälls problem och samtidigt ett miljöproblem i dagens sämhalle är det stora plast berget i Stillahavet. Ett undervisningsmaterial för"Samhällsfrågor Med Naturvetenskapligt Innehåll", SNI, principen har utvärderats med avseende på vilka förmågor som kan tränas tillsammans med huruvida eleverna kan öka sin vetenskapliga kunskap. Studien visade att eleverna kan utveckla nästan alia formågor som beskrivs i läroplanen och sina kunskaper inom naturvetenskapen genom denna typ av utbildningsmaterial. Nyckelord Biomaterial, ligninreaktivitet, tiol medierad demetylering, jodmedierad demetylering,grön kemi, SNI-fall.
Donaldson, Megan Elizabeth. "Development and application of novel solvents for sustainable reactions and separations." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24749.
Повний текст джерелаCommittee Chair: Charles A. Eckert; Committee Co-Chair: Charles L. Liotta; Committee Member: Christopher W. Jones; Committee Member: Facundo M. Fernandez; Committee Member: Thomas F. Fuller.
Nixon, Emily Cummings. "Silanes in sustainable synthesis: applications in polymer grafting, carbon dioxide capture, and gold nanoparticle synthesis." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45847.
Повний текст джерелаSchweitzer, Na'ama. "Greening the Streets: A Comparison of Sustainable Stormwater Management in Portland, Oregon and Los Angeles, California." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/pomona_theses/85.
Повний текст джерелаLo, Enlin. "Sustainable Production of Bio-based Succinic Acid from Plant Biomass." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7693.
Повний текст джерелаAguilera, Bulla Daniel Antonio. "Polysaccharide encapsulated catalysts : towards the sustainable production of fine chemicals." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2019. http://www.theses.fr/2019ENCM0004.
Повний текст джерелаAlginates are natural polysaccharides extracted from brown macro-algae, available in nearly unlimited amounts at very low prices. In the presence of some divalent metals or by lowering the pH, these renewable biopolymers can readily form hydrogels, solvogels and aerogels, characterized by high surface areas, good mechanical properties, tolerance to different media, and easy manageability. In the last years, alginate gels have been gradually used as supports for a varied range of active chemical species in heterogeneous catalysis and as solid acid Brønsted catalyst. In this context, the present work contributes to broaden the use of alginate gels in asymmetric heterogeneous catalysis, exploiting the peculiar features of this class of natural biomaterials. In the first part of this study, the use of alginate gel beads as supports to prepare a heterogenized version of an amino Cinchona alkaloid for asymmetric Michael addition is described. In contrast with the classical immobilization via covalent attachment in oil-derived support, our approach was the immobilization of the organocatalyst using non-covalent interactions. The results presented here demonstrate that the adsorption of a representative Lewis base organic catalyst (9-amino-9-deoxy epi-quinine, QNA) takes place with high yields onto acidic alginate gels (AGs) using a very simple and straightforward protocol. This protocol is robust and fully reproducible. The resulting chiral solvogel beads (QNA@AGs) are active as heterogeneous catalysts in the addition of aldehydes to nitroalkenes, affording the corresponding adducts in good yields and moderate to excellent diastereo- and enantio-selectivities. In these reactions, the carboxylic functions of the biopolymer act as both acidic co-catalyst and non-covalent anchoring site for the tertiary amine catalyst (as observed by IR spectroscopy). The use of heterocationic gels, derived from alkaline earth metal gels by partial proton exchange, provided materials with better mechanical properties and higher porosities, ultimately resulting in higher catalytic activities. The alginate gels were also assessed as a possible way of transfering chirality from the support to a reaction outcome. The Friedel-Crafts alkylation of nitroalkenes with indoles was selected as a model reaction to evaluate preliminarily the enantio-induction by metal Lewis alginate gels. The library of alginate gels tested is active in the benchmark reaction. The Cu and Ba- alginate gels afford good activity and the enantiomeric-induction is proved, obtaining moderate enantiomeric excesses under the optimized reaction conditions. Furthermore, these two metals allow access to both enantiomers of the products, an important aspect given that only one enantiomeric form of alginates is available. Finally, the heterogeneous nature of the catalyst is proved using Cu-alginate gels. The full recyclability is demonstrated, by showing that Cu-alginate gels can be recovered and recycled without loss of stereochemical activity for at least five reaction cycles. This work represents the first utilization of alginates, abundant and renewable biopolymers, as gel supports/media for asymmetric organocatalytic processes and the first example of induction of enantioselectivity for a C-C bonding reaction with interest in the fine chemical industry
Bland, Katherine Elizabeth. "Lignocellulosic fermentation of Saccharomyces cerevisiae to produce medium chain fatty alcohols." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/82720.
Повний текст джерелаMaster of Science
Karunarathna, Mudugamuwe Hewawasam Jayan Savinda. "Photochemistry of iron(III) with carboxylate-containing polysaccharides for sustainable materials." Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1586468303760847.
Повний текст джерелаBrogi, Lorenzo. "Effects of low-environmental impact graphene on paints: chemical and physical properties." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/24415/.
Повний текст джерелаFarnocchia, Giulia, and Giulia Farnocchia. "Evaluating the PHA storage capacity and the impacts of growth conditions on Chloroflexus aurantiacus, a green non-sulphur phototrophic bacterium." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Знайти повний текст джерелаGreco, Enrico. "Development of new Lithium-Transition Metals co-doped Nanotitania. A perspective for sustainable photocatalytic materials and a comparative study between benefits and health risks." Doctoral thesis, Università di Catania, 2017. http://hdl.handle.net/10761/3906.
Повний текст джерелаShi, Yiping. "Conversion of renewable feedstocks into polymer precursors and pharmaceutical drugs." Thesis, University of St Andrews, 2018. http://hdl.handle.net/10023/16461.
Повний текст джерелаWitayakran, Suteera. "Laccase in organic synthesis and its applications." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26665.
Повний текст джерелаCommittee Chair: Ragauskas, Arthur; Committee Member: Bunz, Uwe; Committee Member: Cairney, John; Committee Member: Collard, David; Committee Member: Singh, Preet. Part of the SMARTech Electronic Thesis and Dissertation Collection.
Maza, Lisa Jésus. "Résines vertes à base de lignine organosolve." Thesis, Pau, 2017. http://www.theses.fr/2017PAUU3039.
Повний текст джерелаPhenolic resins, may be used in the wood industry for the manufacture of particle boards or plywood, after gluing, impregnation and/or hot-pressing steps. They are mainly obtained by step polymerization (polycondensation) from formaldehyde and phenol. These two raw materials are currently petrochemicals.This thesis work, supported by Rolkem, a company specialized in the design and manufacture of resol type phenolic resins, aims to reduce the use of non-biobased materials by replacing phenol with lignin exhibiting a phenolic structure and a structural similarity with the network of phenolic resins. Lignin is abundant in the environment and easily available. To achieve the industrialization of these new biobased resins, a study on the understanding of the reaction mechanisms has been carried out to favor the incorporation of lignin within the resins. It has been possible to replace up to 50wt.% of the phenol with organosolve lignin and to reduce the initial concentration of formaldehyde at the same time. 75wt.% substitution has been achieved using a Kraft lignin by reducing up to 30wt.% of the formaldehyde concentration as compared to conventional resins. The new biobased resins respect the Rolkem specifications. Thanks to this work results, the scale transfer of biobased resins from the laboratory scale to the industrial pilot was possible, while respecting industrial constraints such as productivity, quality, safety and environment. In addition, the industrial plywood bonding tests were in accordance with the prerequisite.In addition to the above objectives the reactivity of BiolignineTM with formaldehyde has been studied under conventional heating and microwave irradiation. This complementary study allows the correlation of the lignine-formaldehyde reactivity and the heating modes to specifically reach products resulting from addition or condensation reactions
Farhat, Wissam. "Investigation of hemicellulose biomaterial approaches : the extraction and modification of hemicellulose and its use in value-added applications." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSES032/document.
Повний текст джерелаThe increased use of renewable materials is considered as one of the key issue of the sustainable development. Carbohydrates are readily biodegradable and tend to degrade in biologically active environments. Hemicelluloses (HC) are one of the most common polysaccharides next to cellulose and chitin, representing about 20-35% of lignocellulosic biomass, and have not yet found broad industrial applications as does cellulose. Hemicellulose is a hetero-polysaccharide and a green substitute for petroleum based polyols and is a non-food-based substitute for starch polyols. The aims of this project are to develop an optimized strategy for the extraction of hemicellulose and the use of the extracted hemicellulose in value-added biomaterials. The extraction of hemicellulose would have great potential to supply raw materials for the new bio-economy. To expand its applications to the field of stimuli-responsive hydrogels, coating and adhesives, polymer networks, as well as drug-delivery systems, the properties of hemicellulose were functionalized by introducing reactive groups onto its main chain to reversibly crosslink it by the Diels-Alder reaction. Hemicellulose based materials were prepared and characterized for their suitable application. Finally, the worldwide potential demand for replacing petroleum-derived raw materials by renewable resources in the production of valuable biodegradable polymeric materials is significant from both social and environmental viewpoints fuel and will predominate in the coming periods
Vernes, Léa. "Mise au point d’un procédé innovant d’éco-extraction assisté par ultrasons d’ingrédients alimentaires à partir de spiruline et transposition à l’échelle industrielle." Electronic Thesis or Diss., Avignon, 2019. http://www.theses.fr/2019AVIG0273.
Повний текст джерелаMicroalgae are one of the most promising renewable resource for future sustainable food. Thanks to their diversity of metabolism, these microorganisms can synthesize a wide range of compounds of interest with high nutritional value. However, their consumption remains limited because of their intrinsic organoleptic characteristics unattractive. To tackle this problem and to overcome these barriers, this thesis was focused on the development of a production process of food ingredient from spirulina.A green and innovative method using ultrasonic technology for the extraction of proteins from Arthrospira platensis was proposed in a first part. This is the manothermosonication (MTS). The use of an experimental plan made it possible to optimize extraction parameters; and mathematical modeling and microscopic investigations led to an understanding of the mass transfer phenomena on the one hand, and the structural effects of ultrasound on spirulina filaments on the other hand. According to the experimental results, MTS allowed to obtain 229 % more proteins (28.42 ± 1.15 g / 100 g DW) compared to the conventional method without ultrasound (8.63 ± 1.15 g / 100 g DW). With 28.42 g of protein per 100 g of spirulina in the extract, a protein recovery rate of 50% was achieved in 6 minutes with a continuous MTS process. Based on these promising results, extrapolation tracks have been studied in order to propose decision support tools for process industrialization. Thus, a risk analysis procedure (HACCP & HAZOP), a cost study as well as the environmental impact of the process were developed in a second part of this work. Lastly, ways of exploiting by-products have been presented in a biorefinery approach
Hammarberg, Daniel. "Grön kemi och hållbar utveckling : Laborationsdesign för gymnasium och högskola." Thesis, KTH, Skolan för teknikvetenskaplig kommunikation och lärande (ECE), 2043. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-140231.
Повний текст джерелаDenna uppsats behandar hållbarhet inom kemi, den så kallade gröna kemin. Med arbetet söker jag förena grön kemi med hållbar utveckling och hitta metoder för att undervisa grön kemi i en laborativ miljö. I undersökningen har jag designat och testat två laborationer med inslag av grön kemi och hållbar utveckling. Jag ville undersöka om undervisningsmodellen leder till en begreppsutveckling hos studenter och elever. Studenterna/eleverna har genom enkäter och intervjuer uttalat sig om dels sina egna kunskaper och dels om undervisningens inslag och dess bidrag till deras begreppsutveckling. I ett laborativt sammanhang bör fördelarna med ett laborativt arbetssätt utnyttjas. Förarbete och efterarbete ger laborationen ett sammanhang. Studenten/eleven förstår begreppen bättre om de får testa sina kunskaper i en diskussion. Lärarens roll i diskussionen bör vara att lyfta diskussionsnivån genom att styra samtalet och på ett konstruktivt sätt bidra till att föra diskussionen framåt när det är nödvändigt.
Souza, Soraia Peres Lima de. "Argilas pilarizadas: uma tecnologia limpa na reação de isomerização do óxido de estireno." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=4007.
Повний текст джерелаThis 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.
Moutaoukil, Zakaria. "Synthèse et étude de nouveaux agents de flottation et de démétallisation et leurs applications dans l'industrie des phosphates." Electronic Thesis or Diss., Université Côte d'Azur, 2023. http://theses.univ-cotedazur.fr/2023COAZ4027.
Повний текст джерелаNowadays, the mining industry has seen intense activity in the development of reagents and additives for processing a wide variety of minerals, with a special focus on collectors, depressants, as well as chelating agents. Indeed, these agents demonstrated high performances at industrial level, and more particularly in the phosphate industry.The ultimate goal of this thesis work is to develop new “Home Made” reagents and additives in order to support ongoing developments in the phosphate industry in Morocco and to open new perspectives. Accordingly, our research work is focused on the synthesis and performance evaluation of reagents and additives at laboratory, pilot and industrial scales. In this context, agents, belonging to different chemical classes, have been designed for P2O5 low-grade phosphate beneficiation as well as for heavy metals removal. Indeed, with the increase in the world population and the growing demand for free-heavy metals phosphate fertilizers, it is of utmost importance to focus on the exploitation of P2O5 low-grade phosphates and the elimination of heavy metals. In this context, we developed and evaluated various home-made organophosphorus agents during reverse flotation and precipitation processes. These chemicals have proven to be very effective and have produced high yields. Furthermore, during this thesis work, we were also interested in the design, synthesis and evaluation of new bis-phosphonic acids and dihydropyrimidines, with the aim of enhancing and diversifying the portfolio of P-based products, within the framework of green and sustainable chemistry
Schütze, Mike. "Bimetallic Complexes for Cooperative Polymerization Catalysis." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E4A0-A.
Повний текст джерелаSCELFO, SIMONE. "Metal oxides catalysts for the synthesis of value-added chemicals from 2nd generation sugars and sugar derivatives." Doctoral thesis, Politecnico di Torino, 2017. http://hdl.handle.net/11583/2675152.
Повний текст джерелаWang, Yantao. "Synthesis and conversion of furfural-batch versus continuous flow." Thesis, Compiègne, 2019. http://www.theses.fr/2019COMP2474/document.
Повний текст джерелаFurfural, which has been identified as one of top 30 bio-based chemicals, is an important green platform molecule, The aim of this PhD work is to realize the synthesis and conversion of furfural in batch and continuous flow. Here, we developed sorne greener methods for furfural synthesis, and valorized furfural into high value-added products, such as 2-furonitrile, furfuryl alcohol etc. Several keys issues were identified in order to design processes greener than the current ones. ln detail, experiments for furfural synthesis were performed in water or in water and organic solvent when co-solvents (green or eco-friendly) are necessary. Microwave irradiation has been chosen as the heating method to accelerate the dehydration process, and microwave continuous flow reactor was also applied to improve furfural productivity. When starting from furfural to produce high value-added chemicals, efficient flow reactors, suc as Pheonix, H-cube Pro as well as microwave continuous flow With micro-reactor, were also identified as interesting alternatives to improve the productivities of target compounds. As a result, some promising results were obtained in the viewpoint of industry
Bruniaux, Sophie. "Nouveaux hydrotropes biosourcés : conception, synthèse et propriétés physico-chimiques en milieu hautement salin." Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2378.
Повний текст джерелаHistorically, chemical industry was based on fossil ressources, but alternative processes have been developed since the nineteens to be green and to answer to the environmental eco-responsibility questions. In this context, a collaboration work between three public laboratories and the SAS PIVERT emerged to find new biosourced hydrotropes starting from various polyols – such as glycerol, main byproduct of the fuel production – and resistant to high saline conditions. A specific design was defined by our physico-chemical partner for the synthesis of hydrotropes. Differents approaches were used to obtain these compounds, such as a new method of methylation using sub/supercritical methanol with a phase of optimization, and another about the scope of the reaction that reduced the reaction steps. The transposition of the reductive alkylation of various alcohols was also realized – using a heterogeneous catalysis – with the obtention of various ethers, in continuous flow conditions, by the intermediate of the use of the HCube Pro from ThalesNano
Villoria, del Álamo Beatriz. "Síntesis de catalizadores sólidos orgánicos e híbridos orgánicos-inorgánicos y su aplicación." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/163789.
Повний текст джерела[CA] En aquesta tesi doctoral, la investigació s'ha centrat en el desenvolupament de dife-rents processos catalítics heterogenis emprant materials híbrids orgànic-inorgànics porosos (MOFs i sílices funcionalitzades) i materials orgànics aromàtics (PAFs), que s'han estudiat en diverses reaccions orgàniques. Després de la preparació dels MOFs en estudi, s'han caracteritzat les seues propietats estructurals i s'han determinat els seus centres actius en els clústers metàl·lics (zirconi, hafni o ceri). La reactivitat d'aquests MOFs i dels materials híbrids sílice-amines s'ha estudiat tenint en compte els seus cen-tres catalítics; aquestes reaccions s'han optimitzat duent a termini un estudi dels meca-nismes de reacció. Finalment, s'han preparat sòlids homoquirals de tipus PAF que presenten el sistema binaftilo, la reactivitat del qual també ha sigut provada. Més específicament, en el capítol 3 s'ha estudiat l'esterificació d' amides, que per-met convertir-les en èsters, grups funcionals més versàtils. Aquesta transformació s'ha abordat des de la catàlisi heterogènia via *MOFs basats en zirconi, hafni i ceri de les sèries MOF-808, UiO-66 i MOF-801. El catalitzador més eficient per a l'esterificació d'amides ha sigut el MOF-808-Zr. Mitjançant anàlisi TGA i l'adsorció d'una molècula sonda bàsica (CO) estudiada utilitzant espectroscopia FT-IR, s'han determinat els cen-tres àcids de Lewis i Brönsted presents en ells. Dels MOFs preparats en aquest treball, el MOF 808-Zr posseeix una menor connectivitat dels clústers metàl·lics i una major grandària de porus que el UiO-66 i el MOF-801; a més, té el balanç adequat de centres àcids i bàsics de Brönsted i Lewis per a activar els substrats de la reacció. L'abast de l'alcoholisi amb n-butanol s'ha estés a un gran nombre de substrats (amides primàries, secundàries i terciàries; aromàtiques i alifàtiques). La reacció també s'ha estudiat en condicions no solvolítiques amb alcohols més complexos. El catalitzador és estable durant la reacció i pot ser reutilitzat fàcilment. El mecanisme de reacció en l'esterifica-ció de benzamida amb n-butanol catalitzada per MOF-808-Zr s'ha investigat mitja-nçant l'anàlisi cinètica emprant el model de LHHW i l'estudi in situ de les interaccions moleculars per FT-IR. En el capítol 4, s'ha investigat la deuteració per intercanvi isotòpic deuteri/hidrògen catalitzada per amines suportades en sílices comercials emprant D2O com a font de deuteri. Aquest procediment és aplicable a una gran gamma de substrats, com a com-postos carbonílics, sals d'organofosfoni, nitrocompostos i, inclosa, hormones esteroi-dals. L'estabilitat del catalitzador, SiO2-(CH2)3-NH2, es manté fins a 10 usos de reac-ció sense pèrdues significatives de l'activitat. Finalment, en el capítol 5, s'afronta la síntesi i aplicació de PAFs homoquirals on s'ha integrat l'esquelet del BINOL (1,1′-binaftil-2,2′-diol) i del BINBAM (1,1'-binaftil-2,2'-disulfonimida) generant tres nous PAFs actius en catàlisi asimètrica: PAF-3,3'-(S)-BINOL, PAF-6,6'-(R)-BINOL i PAF 3,3'-(S)-BINBAM. En concret, el PAF-6,6'-(R)-BINOL ha demostrat la seua activitat catalítica en la reacció d'alquilació d'aldehids aromàtics amb dietil-zinc i el catalitzador PAF-3,3'-(S)-BINBAM és actiu en la reacció aldólica de Mukaiyama i la reducció del doble enllaç de compostos carbonílics a,b-insaturats.
[EN] In this Doctoral Thesis, the research has been focused on the development of different heterogeneous catalytic processes using hybrid porous organic-inorganic materials (MOFs and functionalized silicas) and organic aromatic materials (PAFs), which have been studied in various organic reactions. After the preparation of the MOFs under study, their structural properties have been characterised and their active centres in the metal clusters (zirconium, hafnium or cerium) have been determined. The reactivity of these MOFs and the hybrid silica-mine materials has been studied considering their catalytic centres; these reactions have been optimised by carrying out a study of the reaction mechanisms. Finally, homochiral PAF-type solids have been prepared with the binafil system, whose reactivity has also been tested. More specifically, the esterification of amides has been studied in Chapter 3. This reaction allows to convert the amides into esters, which are more versatile functional groups. This transformation has been approached from the heterogeneous catalysis via MOFs based on zirconium, hafnium and cerium of the MOF-808, UiO-66 and MOF-801 series. The most efficient catalyst for amide esterification has been MOF-808-Zr. Using TGA analysis and the adsorption of a basic probe molecule (CO) studied using FT-IR spectroscopy, the acid centres of Lewis and Brönsted present in them have been determined. Among the MOFs prepared in this work, MOF 808-Zr has a lower metal cluster connectivity and a larger pore size than UiO-66 and MOF-801; it also has the appropriate balance of acid and basic Brönsted and Lewis centres to activate the reaction substrates. The scope of n-butanol alcoholysis has been extended to a large number of substrates (primary, secondary and tertiary amides; aromatic and aliphatic). The reaction has also been studied in non-solvolitic conditions with more complex alco-hols. The catalyst is stable during the reaction and can be easily reused. The reaction mechanism in the esterification of benzamide with n-butanol catalysed by MOF-808-Zr has been investigated through kinetic analysis using the LHHW model and the in situ study of molecular interactions by FT-IR. In Chapter 4, the deuteration by isotopic deuterium/hydrogen exchange catalysed by commercial silica-supported amines using D2O as a source of deuterium has been investigated. This procedure is applicable to a wide range of substrates, such as carbonylic compounds, organophosphonium salts, nitro compounds and, even, steroid hormones. The stability of the catalyst, SiO2-(CH2)3-NH2, is maintained for up to 10 reaction uses without significant loss of activity. Finally, in Chapter 5, the synthesis and application of homochiral PAFs, in which the structure of BINOL (1,1′-binaftil-2,2′-diol) and BIN-BAM (1,1' binaftil-2,2'-disulfonimide) has been integrated, is discussed. Three new PAFs active in asymmetric catalysis has been generated: PAF-3,3'-(S)-BINOL, PAF-6,6'-(R)-BINOL and PAF 3,3'-(S)-BINBAM. In particular, PAF-6,6'-(R)-BINOL has demonstrated its catalytic activity in the alkylation reaction of aromatic aldehydes with diethyl zinc and the catalyst PAF-3,3'-(S)-BINBAM is active in the Mukaiyama aldolic reaction and the reduction of the double bond of carbonylic a,b-unsaturated compounds.
Villoria Del Álamo, B. (2021). Síntesis de catalizadores sólidos orgánicos e híbridos orgánicos-inorgánicos y su aplicación [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/163789
TESIS
Gomes, Carla Sofia Loureiro. "Mecanoquímica na síntese de compostos aromáticos com potencial atividade biológica." Master's thesis, 2017. http://hdl.handle.net/10316/83177.
Повний текст джерелаA noção de desenvolvimento sustentável «satisfazer as necessidades do presente sem comprometer a capacidade das gerações futuras de satisfazerem as suas próprias necessidades» foi introduzida na sociedade no início da década de 90. Possuindo uma ampla definição inclui diversas perspetivas, entre as quais a química sustentável e a engenharia sustentável. A química verde definida como a invenção, desenvolvimento e aplicação de produtos químicos e processos, para reduzir ou eliminar, o uso e a formação de substâncias perigosas à saúde humana e ao meio ambiente é uma parte da química sustentável em que se inserem os estudos apresentados nesta dissertação. A mecanoquímica, entendida como a área que estuda as transformações químicas promovidas pela ação mecânica, tem sido alvo de renovada atenção nos últimos anos devido à sua potencialidade para a promoção de reações sem a utilização de solvente eliminando, assim, uma das maiores fontes de desperdícios, de matérias primas e resíduos indesejáveis nos processos químicos. Desde a utilização imemorial do almofariz como “reator” para promover transformações por ação mecânica, vários equipamentos têm sido desenvolvidos para a aplicação de forças mecânicas em sólidos, contudo pela especificidade da aplicação, mantem-se a necessidade de desenvolver reatores dedicados à realização de reações de síntese química. Ao longo do trabalho apresentado nesta dissertação e em colaboração com o Laboratório de Energética e Detónica do Departamento de Engenharia Mecânica da Universidade de Coimbra desenvolveu-se um reator para síntese orgânica via mecanoquímica que se encontra em fase de finalização e de pedido de patente. A condensação de Claisen-Schmidt para a síntese de chalconas foi utilizada como reação modelo no processo de desenvolvimento e construção do reator. Nesta dissertação apresentam-se os estudos realizados na síntese via mecanoquímica de chalconas e porfirinas. A síntese via mecanoquímica revelou-se muito eficaz em ambos casos permitindo a obtenção destes compostos com rendimentos similares ou superiores a outros métodos descritos na literatura. Permitiu ainda reduzir ou eliminar a quantidade de solventes, reduzir os tempos de reação e efetuar a reação a temperatura ambiente dispensando aquecimento. As novas metodologias aproximam-se assim, aos princípios da química verde o que é evidenciado pela quantificação através das métricas, Fator-E completo e EcoScale, dos seus valores ótimos.
The notion of sustainable development 'meeting the needs of the present without compromising the ability of future generations to meet their own needs' was introduced into society in the early 1990s. Having a broad definition, it includes a number of perspectives, including sustainable chemistry and sustainable engineering. Green chemistry defined as the invention, development and application of chemicals and processes to reduce or eliminate the use and formation of substances hazardous to human health and the environment, is a part of sustainable chemistry which includes the studies presented in this dissertation. Mechanochemistry, understood as the area that studies the chemical transformations promoted by mechanical action, has been the subject of renewed attention in recent years due to its potential to promote reactions without the use of solvent, thus eliminating one of the major sources of waste, raw-materials and undesirable residues in chemical processes. Since the immemorial use of the mortar as a "reactor" to promote transformations by mechanical action, several types of equipment have been developed for the application of mechanical forces in solids, however due to the specificity of the application, the need remains for the development of appropriate reactors for carrying out chemical synthesis reactions. Throughout the work presented in this dissertation and in collaboration with the Laboratory of Energetics and Detonation of the Department of Mechanical Engineering of the University of Coimbra a reactor for organic synthesis via mechanochemistry was developed that is in the phase of finalization and patent application. The Claisen-Schmidt condensation for the synthesis of chalcones was used as a model reaction in the process of development and construction of the reactor. In this dissertation the studies carried out in the mechanochemical synthesis of chalcones and porphyrins are presented. Synthesis via mechanochemistry proved to be very effective in both cases allowing the formation of these compounds with yields similar or superior to other methods described in the literature. It also allowed to reduce or eliminate the amount of solvents, reduce the reaction times and carry out the reaction at room temperature. The new methodologies thus approach the principles of green chemistry, which is demonstrated by the quantification through the metrics, Full- E Factor and EcoScale, of their optimal values.
GUMINA, BIANCA. "Sustainable conversion of biomass derived cellulose by using heterogeneous palladium based catalysts." Doctoral thesis, 2018. http://hdl.handle.net/11570/3131227.
Повний текст джерелаPaninho, Ana Inês Brandão. "Sustainable Intensification Strategies for the Production of Cyclic Carbonates from CO2." Doctoral thesis, 2018. http://hdl.handle.net/10362/43093.
Повний текст джерела[PT] O aquecimento global provocado principalmente pelo aumento das concentrações de gases de efeito estufa na atmosfera tornou-se numa das mais sérias preocupações em termos ambientais. Entre os principais gases responsáveis pelo efeito de estufa, temos o dióxido de carbono. Pelo facto de estar bastante disponível, de ser não inflamável, ter baixa toxicidade e devido a sua independência em relação a cadeia alimentar, o uso do CO2 como matéria-prima tem vindo a ganhar muita atenção quer do ponto de vista industrial e quer académico. O objetivo deste trabalho consiste no desenvolvimento de estratégias de intensificação do processo responsável pela produção de carbonatos cíclicos a partir da reação de epóxidos com CO2. Por sua vez, os carbonatos cíclicos produzidos tem várias aplicações, podem ser utilizados como eletrólitos nas baterias de lítio, como intermediários farmacêuticos e também como monómeros para a produção de polímeros. Pela primeira vez, complexos de zinco (II) de arilhidrazonas de -dicetonas combinados com líquidos iónicos foram utilizados como catalisadores na produção de carbonatos cíclicos. Diferentes famílias de aniões e catiões foram estudadas, com o objetivo de compreender o efeito destes grupos funcionais na selectividade e no rendimento final da reação. Os resultados confirmaram a importância da nucleofilicidade do anião, com os iões de halogénios a apresentar os melhores resultados. Preservando à estrutura de catião, foi possível concluir que o tamanho da estrutura era o fator mais importante a ter em consideração. O efeito da pressão, temperatura, tipo de solvente e catalisador foram alguns dos parâmetros estudados, adicionalmente um processo de extração a alta pressão foi proposto como forma eficiente de separação do produto final e reutilização do catalisador. Finalmente, com o objetivo de desenvolver uma tecnologia verde na conversão de CO2 em carbonatos cíclicos duas diferentes abordagens, em termos de engenharia, foram investigadas. Primeiro, foi preparado e devidamente caracterizado um catalisador suportado, composto por uma matriz de aerogéis de alginato, para posteriormente ser testado com sistema catalítico. Segundo, foi explorada a possibilidade de realizar esta reação em modo contínuo, utilizando com líquidos iónicos em “bulk” com catalisadores. Em ambos os processos foi possível a produção de carbonatos cíclicos a partir de um epóxido proveniente de recursos naturais (óxido de limoneno) produzindo assim carbonato de limoneno, um carbonato 100% bio-renovável. Esta tese fornece novas oportunidades para aumentar a produtividade do processo de produção de carbonatos cíclicos a partir do CO2.
Doctoral fellowship PD/BD/52497/2014, FCT/MEC (UID/QUI/50006/2013), ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER - 007265), project EXPL/QEQ-ERQ/2243/2013, project “Sun Storage – Harvesting and storage of solar energy”, reference POCI-01-0145-FEDER-016387, FCT (RECI/BBB-BQB/0230/2012) e AQUA-CO2NV ENE2014-53459-R.
Δροσόπουλος, Δημήτριος. "Ο κοινοτικός κανονισμός REACH για τις επικίνδυνες χημικές ουσίες". Thesis, 2010. http://nemertes.lis.upatras.gr/jspui/handle/10889/3216.
Повний текст джерелаAim 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.