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The Paris Agreement has ambitious targets to limit the global warming below 1.5 °Cin the 21st century. This goal is reflected in the national climate targets, for example, Sweden aims to achieve net zero greenhouse gas emissions by 2045, and thereafter achieve negative emissions. One of the pivotal ways to achieve these goals is by applying the mature bioenergy with carbon capture and storage (BECCS) technology to large-scale industries that emit CO2. Around 6% of the global emissions arise from the pulp and paper industry making them one of the largest localized emitters of biogenic CO2. This makes them suitable for retrofitting BECCS technologies and post-combustion capture (PCC) is one among them. This study presents a techno-economic assessment of an absorption-based PCC unit in SCA Östrand pulp mill. Chemical absorption using MEA and chilled ammonia process (CAP) using NH3 as the solvent are considered in this study. For both the processes, mass and energy balances using Aspen HYSYS were done and validated against published data in literature. Heat integration by applying excess or waste heat from the mill is also considered in this work. CO2 capture from flue gas originating from various emission sources in the mill (recovery boiler, lime kiln and multi-fuel boiler) are considered in different combinations in the analysis. The main key performance indicator (KPI) evaluated in this work is the cost of CO2capture for all the different cases for both the MEA- and chilled NH3-based absorption processes. The minimum cost of CO2 capture for MEA-based absorption process was found to be in the range 37-41 €/tCO2 and for CAP, it was found to be in the range 73-81 €/tCO2. For MEA-based absorption process, the excess low pressure steam from the mill satisfies the steam demand in all the cases, except the one where CO2 is captured from all the three emission sources. For CAP, sufficient excess low pressure steam is present in the mill for all the capture cases due to a lower reboiler duty compared to MEA-based absorption process. An optimal process configuration and capture scenario for the existing design conditions in the mill are derived and justified. A sensitivity analysis was carried out to find the associated bottlenecks from the breakdown of the cost of CO2 capture for each process. The overall BECCS cost is also sensitive to CO2 transport & storage costs. However, it is also clear that incentives for negative emissions will make BECCS an attractive solution for the pulp and paper industry.

Rechargeable aluminium (Al) batteries (RABs) have long-been pursued due to the high sustainability and three-electron-transfer properties of Al metal. However, limited redox chemistry is available for rechargeable Al batteries, which restricts the exploration of cathode materials. Herein, we demonstrate an efficient Al–amine battery based on a quaternization reaction, in which nitrogen (radical) cations (R3N*+ or R4N+) are formed to store the anionic Al complex. The reactive aromatic amine molecules further oligomerize during cycling, inhibiting amine dissolution into the electrolyte. Consequently, the constructed Al–amine battery exhibits a high reversible capacity of 135 mAhg1 along with a superior cycling life (4000 cycles), fast charge capability and a high energy efficiency of 94.2%. Moreover, the Al–amine battery shows excellent stability against selfdischarge, far beyond conventional Al–graphite batteries. Our findings pave an avenue to advance the chemistry of RABs and thus battery performance.

Les composés aminés représentent une grande part des substances actives en chimie médicinale. Les travaux rapportés dans cette thèse décrivent les efforts consacrés au développement d’une nouvelle méthode d’amination de liens C-H propargyliques. Notre groupe de recherche a développé depuis quelques années un nouveau précurseur de nitrène métallique, les N-mésyloxycarbamates, permettant d’effectuer des réactions d’amination de liaisons C-H diversement activées. Au cours du développement de notre méthodologie, la synthèse du N-mésyloxycarbamate a fait l’objet de nombreuses optimisations, notamment en améliorant l’échelle globale de la synthèse ainsi que son efficacité. De même, des efforts ont été consacrés pour diminuer le nombre d’étapes nécessaires à la synthèse du réactif en développant la synthèse d’un des intermédiaires de manière énantiosélective. Enfin, la synthèse de ce réactif a également été envisagée à l’aide de la chimie en flux continu. Au cours du développement de la méthode de synthèse d’amines propargyliques, nous avons constaté que l’acide acétique jouait un rôle déterminant dans la conservation de bonnes sélectivités et réactivités de la réaction. Ces différentes observations ont permis de mettre au point un procédé diastéréosélectif efficace permettant d’obtenir des amines propargyliques avec des rendements allant de moyens à bons et avec d’excellentes diastéréosélectivités. A la suite de l’étude de l’étendue de notre procédé, nous avons tenté de déterminer les mécanismes réactionnels qui régissaient la réactivité et la sélectivité de celui-ci. Nous avons ainsi montré que l’espèce réactive du système catalytique était bel et bien un nitrène métallique, et que l’étape cinétiquement déterminante était celle d’insertion. Des expériences faites en oxydant l’espèce catalytique de rhodium ont suggéré que plusieurs états d’oxydation de cette espèce peuvent être présents et actifs dans le système catalytique. / The nitrogen containing compounds represent a large portion of the active substances in medicinal chemistry. The work reported in this manuscript describe the efforts devoted to the development of a new method of amination of propargylic C-H bonds. Our research group has developed recently a new metal nitrene precursor, N-mesyloxycarbamates, to perform amination reactions on various C-H bonds. During the development of our methodology, the synthesis of N-mesyloxycarbamate has undergone many improvements, including improved global scale synthesis and effectiveness. Similarly, efforts were devoted to reduce the number of steps required for the synthesis of the reagent by developing the synthesis of an intermediate enantioselectively. Finally, the synthesis of this reagent was also considered using continuous flow chemistry. During development of the method of synthesis of propargylic amines, we have found that acetic acid plays a key role in the conservation of good selectivity and reactivity of the reaction. These observations allowed to develop an efficient diastereoselective process in order to obtain propargylic amines with moderate to good yields and with excellent diastereoselectivities. Following the study of the scope of our process, we tried to determine the reaction mechanisms governing the reactivity and selectivity. We have shown that the reactive species of the catalyst system was indeed a metal nitrene, and that the rate-determining step was the insertion. Experiments made by oxidizing the rhodium catalytic species suggested that several oxidation states of this species may be present and active in the catalytic system.

Plasma-based surface modifications offer many interesting possibilities for the production of high value-added polymeric materials. In this work, different plasma-based synthetic concepts were employed to endow poly(ethylene terephthalate) (PET) fabrics with accessible amine functionalities. These concepts were compared to find out the appropriate engineering methods, which can be further accepted by textile industries to overcome the limited reactivity of PET fabric surfaces, while the bulk characteristics are kept unaffected. Amine functionalities were introduced onto the surface of PET fabrics using either low-pressure ammonia plasma treatment or coating oxygen plasma-treated PET fabric with cationic polyelectrolytes. Two different cationic polyelectrolytes were used in this study namely poly(diallyldimethylammonium chloride) as an example of strong polyelectrolytes and poly(vinyl amine-co-vinyl amide) as an example of weak polyelectrolytes. The modified surfaces were characterized by a combination of various surface-sensitive techniques such as X-ray photoelectron spectroscopy (XPS), electrokinetic measurements and time-dependent contact angle measurements. Furthermore, the amine functionalities introduced by different surface modifications were used for the subsequent immobilization of various classes of anionic dyes to evaluate the efficiency of different surface modifications. Color strength (K/S) and fastness measurements of colored fabrics were also explored. Their results can be taken as a measure of the extent of the interaction between different modified surfaces and anionic dyes. Finally, it was demonstrated that anchoring poly(vinyl amine-co-vinyl amide) layer onto PET fabric surfaces modified with low-pressure oxygen plasma is an efficient approach to improve coloration behavior and to overcome different problems related to PET fabrics coloration, such as coloration of PET/wool blend fabric with a single class of dyes. This is a crucial step towards the substrate independent surface coloration, which becomes dependent on the properties of the top layer rather than chemical structure of the fibers.

Doctorat en philosophie et lettres / info:eu-repo/semantics/nonPublished

Plasma-based surface modifications offer many interesting possibilities for the production of high value-added polymeric materials. In this work, different plasma-based synthetic concepts were employed to endow poly(ethylene terephthalate) (PET) fabrics with accessible amine functionalities. These concepts were compared to find out the appropriate engineering methods, which can be further accepted by textile industries to overcome the limited reactivity of PET fabric surfaces, while the bulk characteristics are kept unaffected. Amine functionalities were introduced onto the surface of PET fabrics using either low-pressure ammonia plasma treatment or coating oxygen plasma-treated PET fabric with cationic polyelectrolytes. Two different cationic polyelectrolytes were used in this study namely poly(diallyldimethylammonium chloride) as an example of strong polyelectrolytes and poly(vinyl amine-co-vinyl amide) as an example of weak polyelectrolytes. The modified surfaces were characterized by a combination of various surface-sensitive techniques such as X-ray photoelectron spectroscopy (XPS), electrokinetic measurements and time-dependent contact angle measurements. Furthermore, the amine functionalities introduced by different surface modifications were used for the subsequent immobilization of various classes of anionic dyes to evaluate the efficiency of different surface modifications. Color strength (K/S) and fastness measurements of colored fabrics were also explored. Their results can be taken as a measure of the extent of the interaction between different modified surfaces and anionic dyes. Finally, it was demonstrated that anchoring poly(vinyl amine-co-vinyl amide) layer onto PET fabric surfaces modified with low-pressure oxygen plasma is an efficient approach to improve coloration behavior and to overcome different problems related to PET fabrics coloration, such as coloration of PET/wool blend fabric with a single class of dyes. This is a crucial step towards the substrate independent surface coloration, which becomes dependent on the properties of the top layer rather than chemical structure of the fibers.

Mechanisms of adsorption of alkaline copper quat (ACQ) components in wood were investigated with emphasis on: copper chemisorption, copper physisorption, and quat adsorption. Various factors were investigated that could affect the adsorption of individual ACQ components in red pine wood. Copper chemisorption in wood was affected by ligand types coordinating with Cu and the stability of the Cu-ligand complexes in solution. For Cu-monoethanolamine (Cu-Mea) system, the prevailing active solvent species at the solution pH, [Cu(Mea)2-H]+ complexes with wood acid sites and loses one Mea molecule through a ligand exchange reaction. The amount of adsorbed Cu was closely related to the cation exchange capacity of wood. An increase in Mea/Cu ratio increased the proportion of the uncharged Cu-Mea complex and resulted in decreased Cu chemisorption in wood. Copper precipitation is also an important Cu fixation mechanisms of Cu-amine treated wood. X-ray diffraction analysis revealed that in vitro precipitated Cu was a mixture of copper carbonates (azurite and malachite) and possibly Cu2O. Higher concentration Cu-amine solutions retarded the Cu precipitation to a lower pH because of higher free amine in the preservative-wood system. The changes in zeta potential of wood in relationship to the quaternary ammonium (alkyldimethylbenzylammonium chloride: ADBAC) adsorption isotherm showed two different adsorption mechanisms for quat in wood: ion exchange reaction at low concentration and additional aggregation form of adsorption by hydrophobic interaction at high concentration. Because of the aggregation effect, when wood was treated with ACQ, high amounts of ADBAC were concentrated near the surface creating a steep gradient with depth. This aggregated ADBAC was easily leached out while the ion exchanged ADBAC had high leaching resistance. Free Mea and Cu of ACQ components appeared to compete with ADBAC for the same bonding sites in wood.

The effects of ACQ solution parameters such as copper to quat ratio, pH and copper to ligand ratio on distribution of copper complexes in solution and insoluble precipitates, and on fixation and leaching of copper in treated wood were evaluated. The distribution of ionic complexes, predicted by equilibrium speciation model (MINTEQA2), was related to laboratory fixation and leaching results at controlled ACQ solution parameters. A decrease in the relative proportion of copper in the ACQ formulation from a copper oxide (CuO) to didecyldimethylammonium carbonate (DDACb) ratio of 2:1 to 1:1 and 1:2 resulted in lower copper retention in the treated samples and substantially decreased the amount of copper leached per unit area. For monoethanolamine (Mea) based ACQ, solution parameters which favour a higher proportion of monovalent cationic complex, which consume one reactive site in wood, and the presence of insoluble carbonate precipitate of copper in wood during preservative treatment resulted in higher leach resistance compared to the neutral copper complex present at higher pH. Ammonia (NH3) based ACQ can fix more copper at high pH as there is no chelated neutral complex as in Mea based ACQ; however divalent copper-NH3 complexes may consume two sites to fix in wood. Addition of NH3 in Mea based ACQ at Cu:Mea:NH3 ratio of 1:4:6 at pH 10.6 significantly reduced copper leaching compared to 1:4:0 (without ammonia) at pH 9 due to increased divalent copper-ammonia complexes and decreased neutral copper amine complex at elevated pH. Ammonia addition with a lower proportion of Mea (1:2.5:4 at pH 10.5-10.7), significantly reduced copper leaching compared to 1:4:0 at pH 9; no reduction was observed for ammonia addition in ACQ with a higher proportion of Mea (1:4:4 at pH 10.45). The lower copper leaching from 1:2.5:4 resulted from the higher amount of divalent copper-NH3 complexes at higher pH without compromising the amount of copper precipitated at lower pH. The higher percent copper leached from tetramethylethylenediamine (Tmed) based ACQ compared to Mea and NH3 based ACQ suggested that highly stable complexes tend to stay in solution and do not result in leach resistant copper in the wood.

O neuropeptídeo urocortina 1 (UCN 1) tem entre os seus principais locais de expressão o núcleo de Edinger-Westphal (EW) e o núcleo lateral superior da oliva. Após sua descoberta, sugeriu-se que o EW e o núcleo paraventricular do hipotálamo (PVH) possuíssem papéis complementares e opostos na resposta ao estresse, porém, não existem trabalhos que relacionam anatomicamente núcleos hipotalâmicos e o EW. A fim de contribuir para esta área foi proposto o mapeamento das aferências hipotalâmicas do EW, através da injeção de Fluoro-Gold neste núcleo e posterior mapeamento de suas aferências. Os resultados encontrados foram: PVH, área hipotalâmica lateral (LHA) e o núcleo posterior do hipotálamo (PH) e outras regiões do sistema nervoso central. Para controle, o traçador anterógrado Amina Dextrana Biotinilada, foi injetado nos núcleos/áreas hipotalâmicas PVH, LHA e PH sendo encontradas fibras próximas as células urocortinérgicas do EW. Nossos dados mostram um possível envolvimento das células UCN 1 do EW com o controle de funções autonômicas e neuroendócrinas. / The neuropeptide urocortin 1 (UCN 1) has its main sites of expression at the Edinger-Westphal nucleus (EW) and the lateral superior olivary nucleus. After its discovery has suggested that EW and paraventricular nucleus of hypothalamus (PVH) have complementary and opposing roles in the stress response. However, there are no works relating anatomically the hypothalamic nuclei and EW. To contribute to this area we proposed mapping the hypothalamic afferents of the EW. We have used the Fluoro-Gold injected in the EW as a result of we have found retrogradely labeled cells in the following nuclei: PVH, lateral hypothalamic area (LHA), posterior hypothalamic nucleus (PH) and other regions of the central nervous system. For control, the anterograde tracer biotinylated dextran amine was injected into the nuclei/areas hypothalamic PVH, LHA, and PH we have found anterogradely labeled fibers in a very close apposition over urocortinergic cells at EW. Based on these data we are suggesting a involvement of cells with UCN 1 EW control of autonomic and neuroendocrine functions.