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Wastewater activated sludge is produced during the biological treatment of wastewater. After treating the sewage, the sludge is allowed to settle. Part of the settled material is returned to the treatment process as return activated sludge (RAS) and the excess is removed as waste activated sludge (WAS). The handling and disposal of the sludge are energy and capital-intensive treatments, with a significant environmental impact. This work studies the possibility to utilize RAS (an example of wastewater sludge) as a source of surface active agents. The results indicate that higly surface active materials can be extracted from RAS, and that the RAS extract has potential applications as a detergent and wood adhesive. The results also suggest that recovering a suite of products from RAS, a biological heterogenous source, can be technically feasible. An effective alkaline treatment was developed (at pH>12) that can extract up to 75% of the sludge’s organic matter, a yield higher than previously reported. Increasing the extraction pH increased the extract surface activity, which is linked to increasing the amount of higher molecular weight molecules and the presence of phospholipids. Increasing the extraction pH beyond 11 was also related to extensive cell lysis, increasing significantly the amount of recovered material and the surface activity of the extract. The alkaline extract has properties comparable to commercial detergents. Without further purification, the extract has a low surface tension (37 mN/m on average) and performs similarly to synthetic detergents. Further assessment of the RAS extract (insensitivity to pH, surface tension, interfacial tension) suggests that it may be suitable for commercial applications. The RAS extract can also be formulated into wood adhesives using glutaraldehyde as a crosslinker. The extract fraction with 10-50 kDa constituents at pH 9 achieves high adhesive shear strengths (4.5 MPa on average, at 30% relative humidity and 25°C) with 40% of wood failure. The adhesive strength of RAS-based adhesives is strongly correlated to its protein content.

Biomass is the world’s largest renewable energy source, accounting for approximately 10% of global primary energy supply, and 5% of energy consumed in the United States. Prominent national programs like the U.S. Renewable Fuel Standard incentivize increased use of biomass, primarily as a transportation fuel. There has been comparatively little government support for using biomass as a renewable feedstock for the chemical sector. Such asymmetry in incentives can lead to sub-optimal outcomes in the allocation of biomass toward different uses. Greenhouse gas reduction is among the most cited benefits of bioenergy and bio-based products, however, there is increasing controversy about whether increased use of biomass can actually contribute to greenhouse gas emission targets. If biomass is to play a role in current and future greenhouse gas mitigation efforts its use should be guided by efficient use of natural and economic resources. This thesis addresses these questions through a series of case studies, designed to highlight important tradeoffs in the use of biomass for greenhouse gas mitigation. Should biomass be used as a fuel, a chemical feedstock, or neither? The first case study in this thesis focuses on the ‘fuel vs feedstock’ question, examining the greenhouse gas implications of expanding the scope of the U.S. Renewable Fuel Standard to include credits for bioethylene, an important organic chemical readily produced from bioethanol. Results suggest that an expanded policy that includes bioethylene as an approved use for ethanol would provide added flexibility without compromising greenhouse gas targets – a clear win scenario. Having established that bioethylene based plastics can achieve similar greenhouse gas reductions to bioethanol used as fuel, this thesis expands the analysis by considering how the greenhouse gas emissions from a wider range of bio-based plastics compare to each of the main commodity thermoplastics produced in the U.S. The analysis demonstrates that there are large uncertainties involved in the life cycle greenhouse gas emissions from bio-based plastics, and that only a subset of pathways are likely to be preferable to conventional plastics. The following chapter then builds on the existing model to compare the greenhouse gas mitigation potential of bio-based plastics to the potential for reducing emissions by adopting low carbon energy for plastics production. That chapter concludes that switching to renewable energy across the supply chain for conventional plastics energy cuts greenhouse gas emissions by 50-75%, achieving a greater reduction, with less uncertainty and lower cost, than switching to corn-based biopolymers – the most likely near-term biopolymer option. In the long run, producing bio-based plastics from advanced feedstocks (e.g. switchgrass) and/or with renewable energy likely offers greater emission reductions. Finally, this thesis returns to the dominant form of policy surrounding biomass use: biofuel mandates. That study takes a consequential approach to the ‘fuel or neither’ question. Specifically, this work examines how petroleum refineries are likely to adjust their production in response to biofuel policies, and what this implies for the success of these policies. The research demonstrates that biofuel policies induce a shift toward greater diesel production at the expense of both gasoline and non-combustion petroleum products. This has the potential to result in an increase in greenhouse gas emissions, even before accounting for the emissions from producing the biofuels themselves.

In today’s world the significance of bio-based materials are increasing rapidly because ofthe environmental concern. Material scientists are nowadays engaged in development ofsuch materials which have natural origin and degrade in its environment. Several workshave already been reported in area of thermoplastic biocomposites. However biocompositesbased on thermosets is comparatively new area of research. In this work biobasedcomposites have been developed from two different bio-based thermoset resins.The main objective of the work was room temperature curing of poly lactic acid basedresin (POLLIT™) and AESO, acrylated epoxidized soy-bean oil (TRIBEST®). These tworesin systems were impregnated with different natural fibre mats. Cure behavior wascharacterized by means of DSC (Differential Scanning Calorimeter) and results showsthat the resins have been cured at room temperature. The mechanical properties ofprepared composites were assessed by the means of flexural testing and charpy impacttesting. The viability of using these composites in structural applications are also beendiscussed. / Uppsatsnivå: D

Les résines polyesters sont des composants présents dans une majorité des revêtements et matériaux utilisés aujourd'hui. Ils sont obtenus par polycondensation de polyols, polyacides et monoacides. Les réglementations évoluant (REACH) et le public étant de plus en plus sensible à l'origine et l'impact des produits qu'il consomme, la substitution des produits pétrosourcés vers des matières premières renouvelables semble évidente. De nouveaux polyesters, composés majoritairement de monomères biosourcés, ont donc été synthétisés. L'acide L-(+)-tartrique a été principalement étudié, ce monomère quadri-fonctionnel étant peu utilisé dans la chimie des matériaux bien que disponible en grandes quantités et peu coûteux. Afin de caractériser les polyesters, différents tests utilisés dans l'industrie ont été mis en place, les caractéristiques physico-chimiques pouvant varier d'une application à l'autre. Différents mécanismes de réticulation ont également été explorés afin d'adapter les polyesters aux contraintes de résistance et de séchage requises. Ces mécanismes incluent la réaction entre les hydrazides et les méthyles cétones ainsi que celle des dérivés du Bore et des hydroxyles à température ambiante. La solubilité des polyesters synthétisés a également été étudiée afin d'obtenir un produit soluble en phase aqueuse capable de devenir insoluble après réticulation et séchage / Polyester binders are the main components of the coatings and materials used nowadays. They are obtained by the condensation of polyols, polyacids and monoacids. Evolving regulations (REACH) and the public being increasingly sensitive to the origin and impact of the products it consumes, petro based compounds substitution to renewable raw materials seems obvious. New polyesters, mainly composed of biobased monomers were therefore synthesized. The L-(+)-tartaric acid was mainly studied, this quad-functional monomer being barely used in materials chemistry, although available in large quantities and inexpensive. To characterize polyesters, various tests used in the industry have been established, the physicochemical characteristics may vary from one application to another. Different crosslinking mechanisms have also been explored to adapt polyesters constraints of resistance and drying. These mechanisms include the reaction between the hydrazide and methyl ketones, as well as the derivatives of Boron and hydroxyl at room temperature. The solubility of the synthesized polyesters was also studied in order to obtain a water soluble material capable of becoming insoluble after crosslinking and drying

Phenol formaldehyde (PF) resol resins have long been used widely as wood adhesives due to their excellent bonding performance, water resistance and durability. With the growing concern for fossil fuel depletion and climate change, there is a strong interest in exploring renewable biomass materials as substitutes for petroleum-based feedstock. Bark, rich in phenolic compounds, has demonstrated potential to partially substitute phenol in synthesizing bio-based PF resins. In this study, acid-catalyzed phenol liquefaction and alkaline extraction were used to convert mountain pine beetle (MPB; Dendroctonus ponderosae) infested lodgepole pine (Pinus contorta) barks to phenol substitutes, liquefied bark and bark extractives. Two types of bio-based phenol formaldehyde (PF) resol resins, namely liquefied bark-PF resin and bark extractive-PF resins, were then synthesized and characterized. It was found that acid-catalyzed phenol liquefaction and alkaline extraction were effective conversion methods to obtain phenol substitute with the maximum yield of 85% and 68%, respectively. The bio-based PF resol resins had higher molecular weights, higher polydispersity indices, shorter gel times, and faster curing rates than the lab synthesized control PF resin without the bark components. Based on the lap-shear tests, the bio-based PF resol resins exhibited comparable wet and dry bonding strength to lab PF resin and commercial PF resin. The post-curing thermal stability of the bio-based PF resins was similar to the lab control PF resin. The liquid-state 13C nuclear magnetic resonance (NMR) study revealed significant influences on the resin structures by the inclusion of the bark components. Methylene ether bridges, which were absent in the lab PF resin, were found in the bio-based PF resins. The bark components favored the formation of para-ortho methylene linkages in the bio-based bark extractive-PF resins. The liquefied bark-PF resin showed a higher ratio of para-para/ortho-para methylene link (-CH2-), a higher unsubstituted/substituted hydrogen (-H/-CH2OH) ratio and a higher methylol/methylene (-CH2OH/-CH2-) ratio than the bark extractive-PF resin. Both tannin components of bark alkaline extractives and phenolated barks contributed to the acceleration of the curing rate of the bio-based resins. This research demonstrated the promise of the bio-based PF resins containing either bark alkaline extractives or liquefied barks as environmentally friendly alternatives to PF adhesives derived solely from fossil fuel based phenol and proposed a novel higher value-added application of the largely available barks from the mountain pine beetle-infested lodgepole pine trees.

Wastewater activated sludge is produced during the biological treatment of wastewater. After treating the sewage, the sludge is allowed to settle. Part of the settled material is returned to the treatment process as return activated sludge (RAS) and the excess is removed as waste activated sludge (WAS). The handling and disposal of the sludge are energy and capital-intensive treatments, with a significant environmental impact. This work studies the possibility to utilize RAS (an example of wastewater sludge) as a source of surface active agents. The results indicate that higly surface active materials can be extracted from RAS, and that the RAS extract has potential applications as a detergent and wood adhesive. The results also suggest that recovering a suite of products from RAS, a biological heterogenous source, can be technically feasible. An effective alkaline treatment was developed (at pH>12) that can extract up to 75% of the sludge’s organic matter, a yield higher than previously reported. Increasing the extraction pH increased the extract surface activity, which is linked to increasing the amount of higher molecular weight molecules and the presence of phospholipids. Increasing the extraction pH beyond 11 was also related to extensive cell lysis, increasing significantly the amount of recovered material and the surface activity of the extract. The alkaline extract has properties comparable to commercial detergents. Without further purification, the extract has a low surface tension (37 mN/m on average) and performs similarly to synthetic detergents. Further assessment of the RAS extract (insensitivity to pH, surface tension, interfacial tension) suggests that it may be suitable for commercial applications. The RAS extract can also be formulated into wood adhesives using glutaraldehyde as a crosslinker. The extract fraction with 10-50 kDa constituents at pH 9 achieves high adhesive shear strengths (4.5 MPa on average, at 30% relative humidity and 25°C) with 40% of wood failure. The adhesive strength of RAS-based adhesives is strongly correlated to its protein content.

Phenol formaldehyde (PF) resol resins have long been used widely as wood adhesives due to their excellent bonding performance, water resistance and durability. With the growing concern for fossil fuel depletion and climate change, there is a strong interest in exploring renewable biomass materials as substitutes for petroleum-based feedstock. Bark, rich in phenolic compounds, has demonstrated potential to partially substitute phenol in synthesizing bio-based PF resins. In this study, acid-catalyzed phenol liquefaction and alkaline extraction were used to convert mountain pine beetle (MPB; Dendroctonus ponderosae) infested lodgepole pine (Pinus contorta) barks to phenol substitutes, liquefied bark and bark extractives. Two types of bio-based phenol formaldehyde (PF) resol resins, namely liquefied bark-PF resin and bark extractive-PF resins, were then synthesized and characterized. It was found that acid-catalyzed phenol liquefaction and alkaline extraction were effective conversion methods to obtain phenol substitute with the maximum yield of 85% and 68%, respectively. The bio-based PF resol resins had higher molecular weights, higher polydispersity indices, shorter gel times, and faster curing rates than the lab synthesized control PF resin without the bark components. Based on the lap-shear tests, the bio-based PF resol resins exhibited comparable wet and dry bonding strength to lab PF resin and commercial PF resin. The post-curing thermal stability of the bio-based PF resins was similar to the lab control PF resin. The liquid-state 13C nuclear magnetic resonance (NMR) study revealed significant influences on the resin structures by the inclusion of the bark components. Methylene ether bridges, which were absent in the lab PF resin, were found in the bio-based PF resins. The bark components favored the formation of para-ortho methylene linkages in the bio-based bark extractive-PF resins. The liquefied bark-PF resin showed a higher ratio of para-para/ortho-para methylene link (-CH2-), a higher unsubstituted/substituted hydrogen (-H/-CH2OH) ratio and a higher methylol/methylene (-CH2OH/-CH2-) ratio than the bark extractive-PF resin. Both tannin components of bark alkaline extractives and phenolated barks contributed to the acceleration of the curing rate of the bio-based resins. This research demonstrated the promise of the bio-based PF resins containing either bark alkaline extractives or liquefied barks as environmentally friendly alternatives to PF adhesives derived solely from fossil fuel based phenol and proposed a novel higher value-added application of the largely available barks from the mountain pine beetle-infested lodgepole pine trees.

Cette thèse traite la préparation et l'application d’élastomères bio-sourcés et leurs nanocomposites qui sont les suivants : (1) des nanocomposites basés sur le 3,9 - bis [ethyl-2-à 1,1 terne {b-(3-tertbutyle-4-hydroxy-5-méthylephényle) propionyloxy} éthyle]-2,4,8,10-tetraoxaspiro-[5,5]-undécane (AO-80) et le poly(itaconate de diisoamyle-co-isoprène) (PDII), (2) le poly(itaconate de dibutyle-co-isoprène-co-acide méthacrylique) (PDIM), un élastomère carboxylique bio-sourcé, et des nanocomposites basés sur cet élastomère et la silice ou les nanotubes de halloysite, (3) le poly(itaconate de dibutyle-co-butadiène) (PDIB), un nouvel élastomère bio-sourcé, et des nanocomposites basés sur cet élastomère et la silice. Des pneus verts bio ont été fabriqués en utilisant les nanocomposites PDIB/silice dans une formulation de bande de roulement de pneu. En plus de la préparation de ces dits élastomères bio et leurs nanocomposites, cette thèse donne aussi une revue sur les travaux sur des liaisons sacrificielles bio-inspirées qui sont introduites dans des matériaux polymères. Cette revue servira d'un guide pour incorporer des liaisons sacrificielles dans des élastomères à base d’itaconate ayant une grande rigidité et résistance / This thesis deals with the preparation and application of itaconate based engineering elastomers and their nanocomposites. The following elastomers or nanocomposites were prepared: (1) nanocomposites based on 3,9-bis[1,1-dim ethyl-2-{b-(3-tertbutyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]-2,4,8,10-tetraoxaspiro-[5,5]-undecane (AO-80) and poly(diisoamyl itaconate-co-isoprene) (PDII), (2) a bio-based carboxylic elastomer, poly(dibutyl itaconate-co-isoprene-co-methacrylic acid) (PDIM), and nanocomposites based on it and silica or halloysite nanotubes, (3) a novel bio-based elastomer, poly(dibutyl itaconate-co-butadiene) (PDIB), and nanocomposites based on it and silica. Bio-based green tires were manufactured by using PDIB/silica nanocomposite in a tire tread formulation. In addition to the preparation of the above bio-based elastomers and their nanocomposites, this thesis also gives a review on the progresses on bio-inspired sacrificial bonds in polymeric materials. This review will serve as a guide to engineer sacrificial bonds into itaconate based elastomers with high strength and toughness

A utilização das fontes não-renováveis de energia, como o petróleo e seus derivados, tem proporcionado elevados índices de desenvolvimento em algumas nações, mas também tem causado sérios impactos ao meio ambiente. Diante disso, este trabalho visualiza as mudanças do macro-ambiente dos biocombustíveis no transcurso do tempo, num olhar comparativo a uma rota energética proposta nos anos 30 nos Estados Unidos pelo Movimento Chemurgic. Transcorridos 70 anos de uso de derivados de petróleo, a produção e o uso de biocombustíveis passou a ser um tema de grande relevância no âmbito energético mundial, principalmente devido ao aquecimento global, ocasionado pela concentração do dióxido de carbono na atmosfera. Reporta-se no transcurso do tempo, uma clara participação das inovações tecnológicas no desenvolvimento dos biocombustíveis e dos biomateriais, cuja difusão no presente se dá sob condicionantes de natureza política e ambiental. Para tanto, procurou-se determinar a participação das variáveis de emergência econômicas, sociais, políticas, ambientais e tecnológicas que caracterizam o mencionado macro-ambiente do desenvolvimento e uso de materiais de origem agrícola na produção de combustíveis renováveis, por meio de uma analise léxica e de conteúdo na literatura científica mundial numa interpretação qualitativa dos textos científicos mediante a utilização de um software, que identificou a freqüência de citação das palavras-chave de cada dimensão estabelecida, em que a analise documental permitiu a elaboração de mapas conceituais atuais e retrospectivos, representando o comportamento e desenvolvimento dos biocombustíveis. Considera-se finalmente que, diante de uma visível deterioração ambiental, da poluição atmosférica em particular, os fatores socioeconômicos e políticos de maior importância que promoveram o uso dos biocombustíveis e os biomateriais nos anos 30, abriram lugar para os fatores de natureza ambiental que, paralelamente, promovem a ampliação da produção e do uso dos biomateriais. / The use of non-renewable sources of energy, like petroleum and its derivatives, has been providing high development levels in some nations, but also has been causing serious impacts on the environment. Thus, this work visualizes the changes on biofuel’s macro-environment through the time, in a comparative view of an energetic route proposed in the 30’s in United States by the Chemurgic Movement. Passed 70 yeas of using petroleum derivates, the production and the use of biofuel turned to be a theme of great relevance on energetic world circuit, especially because of global warming, caused by the concentration of Carbon dioxide on atmosphere. It is alluded, in the course of time, a clear participation of technological innovations on the biofuel and biomaterials’ development, whose diffusion in present time happens according to political and environmental conditioners. To do so, it attempted to stipulate the participation of the economical, social, political, environmental and technological emergent variables that characterize the mentioned macro-environment of development and use of agricultural origin materials in the renewable fuel production, through a lexical and content analysis on the world scientific literature in a qualitative interpretation of scientific texts using one Software, which set the keywords citation frequency in each established dimension, in which the documental analysis allowed to elaborate actual and retrospective conceptual maps, representing biofuel’s behavior and development. It is considered, as a conclusion, that, facing a visible environmental degradation, in particular the atmospheric pollution, the most important social-economical and political factors that promoted the use of biofuel and biomaterial in the 30’s, giving place to environmental factors that, in the same time, promote the increase of production and use of biomaterials.