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Thermal degradation (pyrolysis) and chemical digestion of carbon nanotube polymer compositesAkinyi, Caroline J. 19 June 2015 (has links)
No description available.
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Sustainability measures in quicklime and cement clinker productionEriksson, Matias January 2015 (has links)
This thesis investigates sustainability measures for quicklime and cement clinker production. It is the aim of this thesis to contribute to the effort of creating a more sustainable modus of industrial production. The methods used comprises process simulations through multicomponent chemical equilibrium calculations, fuel characterization and raw materials characterization through dynamic rate thermogravimetry. The investigated measures relate to alternative fuels, co-combustion, oxygen enrichment, oxyfuel combustion, mineral carbonation and optimizing raw material mixes based on thermal decomposition characteristics. The predictive multicomponent chemical equilibrium simulation tool developed has been used to investigate new process designs and combustion concepts. The results show that fuel selection and oxygen enrichment influence energy efficiency, and that oxyfuel combustion and mineral carbonation could allow for considerable emission reductions at low energy penalty, as compared to conventional post-combustion carbon dioxide capture technologies. Dynamic rate thermogravimetry, applied to kiln feed limestone, allows for improved feed analysis with a deeper understanding of how mixing of different feed materials will affect the production processes. The predictive simulation tool has proven to be of practical value when planning and executing production and full scale campaigns, reducing costs related to trial and error. The main conclusion of this work is that several measures are available to increase the sustainability of the industry.
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Analysis of vegetable oils, seeds and beans by TGA and NMR spectroscopyRetief, Liezel 03 1900 (has links)
Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Due to the commercial, nutritional and health value of vegetable oils, seeds and beans, the
analysis of their components is of much interest. In this dissertation oil-containing food
products, specifically vegetable oils, seeds and beans, were investigated.
Selected minor components of three locally produced vegetable oils, namely apricot
kernel, avocado pear and macadamia nut oils were investigated using 31P NMR
spectroscopy. These minor components, including 1,2 diacylglycerols, 1,3 diacylglycerols
and free fatty acids, were identified in the 31P NMR spectra of each of the three vegetable
oils for the first time. Two approaches were used for the quantification of the minor
components present in the spectra. A calibration curve approach used known
concentrations of standard minor components to establish calibration curves while a direct
correlation approach calculated the unknown concentration of minor components in the
vegetable oils using a known amount of standard compound within the analysis solution.
These approaches aided in determining the concentration of minor components during
storage studies in which vegetable oils were stored in five different ways: exposed to light,
in a cupboard, in a cupboard wrapped in tin foil, at -8 °C and at 5 °C. It was found that
determining the best storage condition for each oil was difficult since individual minor
components were affected differently by the various storage conditions. However, in
general the best storage conditions appeared to be 5 °C and -8 °C.
The oil, protein and carbohydrate contents of sesame, sunflower, poppy, and pumpkin
seeds, and soy, mung, black and kidney beans were analysed by thermogravimetric
analysis and 13C NMR solid state NMR spectroscopy. It was shown that the first derivative
of TGA data for seeds and beans can give valuable information about the carbohydrate,
moisture, protein and fat content. This has not been previously demonstrated. For the
seeds, the integration of a region between 270–480 ºC was equal to the sum of the oil and
protein content and compared well to quantitative results obtained by other conventional
methods. For beans the integration of a region between 180-590 ºC, gave a value which
represented the sum of the oil, protein and carbohydrate content.
13C solid state NMR spectroscopy, including SPE-MAS, CP-MAS and variable contact time
experiments, was carried out on these seeds and beans and gave valuable information on
the solid-like and liquid-like components. To our knowledge these seeds and beans have
never been previously analysed using this technique. 13C SPE-MAS NMR spectroscopy
indicated that the seeds contained more liquid-like components than the beans. In turn the
13C CP-MAS NMR spectra indicated that beans had higher levels of solid-like components
than the seeds. These conclusions correlated well with the quantities of liquid-like
components and solid-like components that were determined by conventional methods
and TGA. Preliminary studies using T1pH experiments on the components present in the
seeds and beans led to a few observations. Most interesting is that a model using a two-
phase fit in order to determine T1pH values appears to be more accurate than a one-phase
model. / AFRIKAANSE OPSOMMING: Groente olies, sade en bone is ‘n onderwerp van groot belang omrede hul kommersiële,
voeding en gesondheidswaardes. In hierdie tesis is olie-bevattende voedselprodukte,
spesifiek groente-olies, sade en bone geanaliseer.
Geselekteerde komponente teenwoordig in klein hoeveelhede in drie lokaal
geproduseerde groente-olies, naamlik appelkoos-pit, avokadopeer en makadamia-neut
olies is geanaliseer met behulp van 31P KMR spektroskopie. Hierdie komponente,
insluitend 1,2 diasielglyserole, 1,3 diasielglyserole en ongebonde vetsure, is vir die eerste
keer geïdentifiseer in die 31P KMR spektra van die drie groente olies. Twee benaderings is
gebruik vir die hoeveelheids-bepaling van die komponente in die spektra. ‘n Yking-kurwe
metode het gebruik gemaak van bekende hoeveelhede konsentrasies standaard
komponente vir die opstel van yking-kurwes, terwyl ‘n direkte korrelasie metode gebruik is
om die onbekende konsentrasie van komponente in groente olies te bepaal met behulp
van ‘n bekende hoeveelheid standaard verbinding teenwoordig in die oplossing. Hierdie
metodes het gelei tot die bepaling van die konsentrasies van die komponente gedurende
vyf verskillende berging toestande wat ingesluit het: Blootgestel aan lig, in ‘n donker kas,
in ‘n donker kas toegevou in tin foelie, bevries by -8 °C en in ’n koelkas by 5 °C. Dit was
bevind dat bepaling van die beste bergingstoestand vir elke olie moeilik is aangesien die
individuele komponente verskillend geaffekteer word deur die verskeie berging toestande.
Die beste bergings toestand oor die algemeen blyk egter om by 5 °C en -8 °C te wees.
Sesamsaad, sonneblomsaad, papawersaad en pampoensaad sowel as sojaboontjie,
mungboontjie, swartboontjie en pronkboontjie se olie, protein en koolhidraat komponente
was geanaliseer met behulp van termogravimetriese analise (TGA) en 13C soliede
toestand KMR spektroskopie. Dit was bevind dat die eerste afgeleide van die TGA data
waardevolle inligting lewer oor die komponent inhoud van elk van die sade en bone.
Hierdie is nog nie vantevore bevind nie. Vir die sade, was die integrasie van ‘n area tussen
270–480 ºC gelyk aan die som van die olie en proteïen inhoud en het goed vergelyk met
die waardes verky deur algemene analitiese metodes. Vir die boontjies, was die integrasie
van ‘n area tussen 180-590 ºC gelyk aan die som van die olie, protein en koolhidraat
inhoud.
13C vaste staat KMR spektroskopie, insluitende SPE-MAS, CP-MAS en variëerbare
kontak-tyd eksperimente, was gedoen en het waardevolle inligting gelewer omtrent die
solied-agtige en mobiel-agtige komponente. Hierdie sade en bone is tot ons kennis nog
nie van te vore met die tegnieke ondersoek nie. 13C SPE-MAS NMR spektroskopie het
aangedui dat daar ‘n groter hoeveelheid mobiel-agtige komponente in sade as in bone
teenwoordig is. 13C CP-MAS NMR spektroskopie het weer aangedui dat daar ‘n groter
hoeveelheid solied-agtige komponente in bone as in sade teenwoordig is. Hierdie
gevolgtrekkings het goed vergelyk met die waarnemings verkry deur konvensionele
analitiese metodes en TGA. Voorlopige studies op die komponente van sade en bone deur
T1pH eksperimente het tot ‘n paar gevolgtrekkings gelei waarvan die mees interessantste
was dat ‘n twee-fase model vir die bepaling van T1pH waardes beter resultate lewer as ‘n
een-fase model.
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Etude expérimentale et théorique des paramètres régissant la combustion du noir de carbone au cours d'une analyse thermogravimétrique / Experimental and theorical study of the parameters governing the carbon black combustion during thermogravimetry analysisZouaoui, Nabila 17 December 2009 (has links)
La combustion du noir de carbone (NC) dans le creuset d'une thermobalance est contrôlée à la fois par la réaction et par le transport de l'oxygène jusqu'à la surface du lit et à l'intérieur du lit poreux de NC.Les expériences menées en modifiant la masse de NC ont montré que la concentration en oxygène peut tomber à zéro avant d'atteindre le fond du lit. Ainsi, à un instant donné, seule une partie du lit est en combustion. Cette masse, appelée masse critique (mc) dépend de la température. Elle passe de 35 mg à 570°C à 17,5 mg à 650°C.Un gradient d'oxygène s'établi donc dans le lit. La modélisation du transport interne de l'oxygène a montré que la diffusion de Fick constitue une bonne approximation pour représenter ce transport.Des conseils pour extraire correctement une constante cinétique à partir d'expériences thermogravimétrique sont donnés. La procédure est adaptée en fonction de la précision souhaitée.Ainsi, l'utilisation de faibles masses afin de réduire au mieux l'effet de la masse et l'exothermicité de la réaction est fortement conseillée. L'influence de la diffusion externe du gaz peut être réduite en utilisant des creusets de très faibles hauteurs, ou en mettant l'échantillon le plus proche de la bouche du creuset en remplissant le fond du creuset avec un matériau inerte. / Combustion of carbon black (CB) in the crucible of a thermobalance is controlled by both carbon reactivity and oxygen transport from the oxidizing flux to the surface of the bed and within the porous bed.The experiments conducted by changing the mass of CB showed that the oxygen concentration can fall to zero before the bottom of the bed. Thus, at a given time, only a part of the bed is burning. This mass, called critical mass (mc), depends to temperature. It went from 35 mg at 570°C to 17.5 mg at 650°C.An oxygen gradient is thus established in the bed. The Modelling of the internal transport of oxygen showed that the Fick diffusion is a good approximation to represent the transport.Advices to correctly extract a kinetic constant using thermogravimetric experiments are given. The procedure is adjusted depending to the precision desired.Thus, the use of low masses to best reduce the mass and exothermic reaction effects is strongly recommended. The influence of stagnant gas can be reduced by using crucibles with very low height, or by placing the sample closest to the mouth of the crucible by filling the bottom of the crucible with an inert material.
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Síntese, caracterização e estudo termoanalítico de isonicotinatos de lantanídeos e ítrio no estado sólido /Nunes, Wilhan Donizete Gonçalves. January 2018 (has links)
Orientador: Flávio Junior Caires / Banca: Edilene Cristina Ferreira / Banca: Roni Antônio Mendes / Banca: Jose Marques Luiz / Banca: Rita de Cassia da Silva / Resumo: O presente trabalho visa à síntese, caracterização e estudo termoanalítico dos isonicotinatos de lantânio(III), cério(III), praseodímio(III), neodímio(III), samário(III), európio(III), gadolínio(III), térbio(III), disprósio(III), hólmio(III), érbio(III), túlio(III), itérbio(III), lutécio(III) e ítrio(III) no estado sólido. A síntese foi realizada por precipitação, tendo como precursores o ácido isonicotínico, e os óxidos dos respectivos metais. A caracterização dos compostos obtidos foi realizada empregando-se métodos analíticos clássicos, e as técnicas de Termogravimetria e calorimetria exploratória diferencial simultânea (TG-DSC), espectroscopia de absorção na região do infravermelho (IV) com transformada de Fourier (FTIR), termogravimetria acoplada à espectroscopia de absorção na região do infravermelho (TG/FTIR), calorimetria exploratória diferencial (DSC), e difração de raios X pelo método do pó (DRXP). A partir dos dados das análises a estabilidade térmica, comportamento térmico, principais produtos gasosos liberados durante a decomposição térmica, estequiometria, quantidade e modo de interação das moléculas de água presentes, cristalinidade e modo de coordenação metal-ligante foram determinados. Os resultados foram ainda comparados com dados da literatura. / Abstract: The present work aims at the synthesis, characterization and thermoanalytical study of isonicotinates of lanthanum (III), cerium (III), praseodymium (III), neodymium (III), samarium (III), europium (III), gadolinium (III), dysprosium (III), holmium (III), erbium (III), thulium (III), ytterbium (III), lutetium (III) and yttrium (III) solid. The synthesis was carried out by precipitation, having as precursors the isonicotinic acid, and the oxides of the respective metals. The characterization of the obtained compounds was carried out using classical analytical methods, and the techniques of thermogravimetry and simultaneous differential scanning calorimetry (TG-DSC), absorption spectroscopy in the infrared (IV) region with Fourier transform (FTIR), coupled thermogravimetry infrared absorption spectroscopy (TG / FTIR), differential scanning calorimetry (DSC), and X-ray diffraction by the powder method (XRD). From the analysis data the thermal stability, thermal behavior, main gaseous products released during thermal decomposition, stoichiometry, amount and mode of interaction of the water molecules present, crystallinity and mode of metal-bonding coordination were determined. The results were also compared with data from the literature. / Doutor
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L'hydrazine borane et ses dérivés, nouveaux matériaux pour le stockage chimique de l'hydrogène / Hydrazine borane and derivatives, news materials for chemical hydrogen storageMoury, Romain 15 October 2013 (has links)
Dans ce manuscrit, nous trouverons l'étude et la caractérisation de 3 nouveaux matériaux pour le stockage chimique de l'hydrogène : l'hydrazine borane (N2H4BH3, HB avec 15.3 % m H) et les hydrazinidoboranes de lithium (LiN2H3BH3, LiHB avec 11.6 % m H) et de sodium (NaN2H3BH3, NaHB avec 8.8 % m H). Ces matériaux font partie de la famille des boranes, récemment envisagés comme des matériaux prometteurs pour le stockage chimique de l'hydrogène. Comme exemple type, nous pouvons citer l'ammoniaborane (NH3BH3, AB avec 19.6 % m H), car il possède une capacité massique théorique en hydrogène élevée et débute sa déshydrogénation à une température modérée (122°C). Cependant, la cinétique de déshydrogénation de AB est lente. En outre, des gaz nocifs à la pile à combustible, tel que de la borazine, sont émis au cours de la thermolyse. Dans ce contexte, des dérivés, à savoir les amidoboranes, ont été synthétisés pour améliorer les performances de AB. En effet, les amidoboranes de lithium (LiNH2BH3) et de sodium (NaNH2BH3) génèrent 10.9 et 7.5 % m H (respectivement) à 90°C sans période d'induction et sans formation de borazine. Pour notre étude, nous avons choisi de suivre une stratégie similaire de déstabilisation ; nous avons travaillé sur la modification chimique du HB. Dans le premier chapitre nous présentons le protocole de synthèse de HB ainsi que sa caractérisation chimique, structurale et thermique. La synthèse, une métathèse de sel, a été une optimisation du protocole mis en place en 1961 par Goubeau et Ricker. Nous l'avons optimisé en termes de coût, de rendement (≈ 80 %) et de pureté (≥ 99 %). Les caractérisations chimique et structurale nous ont révélé la présence d'un réseau de liaisons Hδ+•••Hδ-, ce qui confère à HB son état solide ainsi que sa stabilité à température ambiante. Cependant, ce réseau ne met pas en jeu la totalité des motifs de HB, au contraire de AB. Les caractérisations thermiques nous ont confirmé cette observation par une diminution de la température de début de déshydrogénation d'environ 60°C et l'absence de période d'induction lors de la décomposition isotherme. Aucune émission de borazine n'a été enregistrée. Cependant, nous avons mis en avant la formation de N2H4 et de NH3. Par des mesures volumétriques, nous avons enregistré que HB est capable de libérer 6.2 % m H en 3 h à 110°C. Les deux chapitres suivants traitent de la synthèse et caractérisation des hydrazinidoboranes de lithium (chapitre II) et de sodium (chapitre III). Les analyses chimique et structurale ont mis en avant une augmentation du degré de liberté du groupement BH3 pour ces deux matériaux par rapport celui de HB, mais aussi la présence d'un réseau de liaisons Hδ+•••Hδ- moins complexe que dans HB. La synthèse de LiHB donne lieu à la formation de deux polymorphes notés ici α- et β-LiHB. Dans nos conditions, NaHB et LiHB ont présenté des propriétés de déshydrogénation plus intéressantes que HB, avec une déshydrogénation totale lorsqu'ils sont tous deux soumis à une rampe de température. En outre, il a été remarqué une nette diminution de l'émission de NH3 (sans N2H4). Pour NaHB, cette émission peut être supprimée par l'ajout d'un excès de NaH lors de la synthèse. La cinétique de déshydrogénation est également améliorée. Nous avons enregistré une déshydrogénation quasi-totale en 1 h à 150°C pour LiHB (2.6 équiv. H2) et en 24 s à 110°C pour NaHB (2.5 équiv. H2). NaHB montre par ailleurs un comportement non conventionnel lors de sa décomposition à des températures supérieures à 100°C ; il libère la quasi-totalité de son hydrogène en quelques minutes à une vitesse de 4 L H2/min à 110°C. Ces matériaux ont donc démontrés leur potentiel pour le stockage chimique de l'hydrogène. / In this manuscript, we present the study and characterization of three new materials for chemical hydrogen storage: i.e. hydrazine borane (N2H4BH3, HB with 15.3 wt % H), lithium and sodium hydrazinidoboranes (LiN2H3BH3, LiHB with 11.6 wt % H and NaN2H3BH3, NaHB with wt 8.8 % H). These materials belong to boranes' family, which have recently been seen as promising materials for chemical hydrogen storage. A typical example of such materials is ammoniaborane, which has a high theoretical hydrogen content (NH3BH3, AB with 19.6 wt % H) and starts it dehydrogenation at moderate temperature (122°C). However, the dehydrogenation kinetics of AB is slow. In addition, some gaseous impurities are detected; e.g. borazine has been often reported to form. In this context, derivatives of AB, i.e. amidoboranes, have been synthesized with the objective to improve the dehydrogenation properties of the parent AB. Lithium and sodium amidoboranes (LiNH2BH3 and NaNH2BH3) generates 10.9 and 7.5 wt % H (respectively) at 90 ° C without any induction period and no borazine formation. For our study, we have chosen to follow a similar strategy in order to destabilize HB by chemical modification. In the first chapter, we report the synthesis protocol of HB and its chemical, structural and thermal characterizations. The synthesis, which is a salt metathesis, is an optimization of the protocol established in 1961 by Goubeau and Ricker. We optimized it in terms of cost, yield (≈ 80%) and purity (≥ 99%). The chemical and structural characterizations have revealed the presence of a Hδ+••• Hδ- network conferring the solid state to the borane as well as its stability in room conditions. However, the network does not involve all of the HB molecules unlike in the case of AB. Thermal characterizations have confirmed this observation through a decreased onset temperature of about 60 °C and the absence of an induction period. No emission of borazine was besides recorded. However, we put forward the formation of N2H4 and NH3. By volumetric measurements, we demonstrated that HB is able to release 6.2 wt % H2 in 3 h at 110 ° C. Chapters II and III deal with the synthesis and characterization of lithium (Chapter II) and sodium (Chapter III) hydrazinidoboranes. We performed detailed chemical and structural characterizations that revealed an increase of the degree of freedom of the BH3 group for these materials compared to HB, but also the presence of the Hδ+ •••Hδ- network but it is less complex than in HB. The LiHB synthesis has put forward the formation of two polymorphs, here noted α- and β-LiHB. In our conditions, Na- and Li-HB have presented more attractive dehydrogenation properties compared to HB, with a total dehydrogenation and a net decrease in the emission of NH3 (without N2H4) when both materials are subjected to a temperature ramp. The emission of unwanted NH3 can be hindered for NaHB by adding an excess of NaH during the synthesis. The dehydrogenation kinetics is also improved. We recorded an almost complete dehydrogenation with 2.6 equiv. H2 in 1 h at 150 ° C for LiHB and with 2.5 equiv. H2 in 24 s at 110 ° C for NaHB. Note that NaHB shows an unconventional behavior upon isothermal decomposition at temperatures above 100 ° C since it releases substantially all of its hydrogen in few minutes with the very high rate of 4 L H2/min at 110 ° C. These materials have thus demonstrated their potential for chemical hydrogen storage.
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Thermal Characterization And Kinetics Of Diesel, Methanol Route Biodiesel, Canola Oil And Diesel-biodiesel Blends At Different Blending Rates By Tga And DscTopa, Ece Hatice 01 September 2010 (has links) (PDF)
Application of thermogravimetric analysis to the renewable energy sources is a novel
study and it has been becoming attractive by the researchers in recent years. In this
thesis, thermal and kinetic properties of biodiesel as new energy source, diesel and
canola oil have been analyzed by using very popular thermogravimetric analysis
methods which are / Differential Scanning Calorimetry (DSC) and Thermogravimetry
(TGA/DTG). The main aim of the study is to observe the combustion and pyrolysis
behaviour of methanol route biodiesel and diesel blends at different blending rates.
Additionally, combustion and pyrolysis behaviour of canola oil, the origin of biodiesel
have been analysed to observe the transesterification reaction effect on biodiesel.
Therefore, biodiesel, diesel, canola oil and blends of diesel and biodiesel at different
percentages are exposed to isothermal heating under nitrogen and air atmosphere with a
constant heating rate of 5, 10 and 15
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Effect of different types of coal in thermal performance of economisers in power stations.Aphane, Manthulane Hezekiel. January 2014 (has links)
M. Tech. Mechanical Engineering. / Discusses the economiser design to absorb as much heat as possible within the flue gases. Fly ash particles, a product of combustion, entrained in the flue gas of the furnace part of the boiler in coal fired boilers, affect economiser thermal performance by causing erosive wear and scale on the outer surface of the economiser tubes along the flow path, which in turn increases the thermal resistance characterisation of coals in relation to combustion behaviour traditionally relies on staged quenching of the reaction and subsequent gravimetric analysis of the remaining sample. Three typical steam-raising coals are compared with regard to reactivity and broadly examined relative to their petro-graphic constituents and other standard laboratory tested samples. A significant correlation was found between the ignition temperature and the hydrogen or carbon ratio determined by the ultimate analysis, inter alia, the erosion rate and the heat transfer rate.
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Síntese, caracterização e estudo termoanalítico dos nicotinatos de lantanídeos (III) e de ítrio (III), no estado sólido / Synthesis, characterization, and thermoanalytical study of nicotinate lanthanide (III) and yttrium (III), in the solid stateColman, Tiago André Denck 19 February 2016 (has links)
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Previous issue date: 2016-02-19 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Foram sintetizados os compostos LnL3•2H2O, sendo que Ln representa os lantanídeos trivalentes (La ao Lu e o ítrio (Y) e o L representa o nicotinato (C6H4NO2--). Os compostos foram sintetizados por adição do ácido nicotínico em carbonatos de lantanídeos e ítrio, sob agitação e aquecimento. A caracterização dos compostos no estado sólido, foi realizada utilizando as técnicas de difratometria de raios X pelo método do pó, complexometria, espectroscopia de absorção na região do infravermelho com transformada de Fourier (FTIR) e pelas técnicas termo analíticas: termogravimetria e calorimetria exploratória diferencial simultâneas (TG-DSC), calorimetria exploratória diferencial (DSC), analise dos gases desprendidos (EGA) por espectroscopia de absorção na região do infravermelho com transformada de Fourier (EGA:TG-FTIR) e termomicroscopia. Os resultados forneceram informações sobre o comportamento térmico, estequiometria dos compostos estudados, cristalinidade, sítios de coordenação e também foi possível identificar os principais produtos gasosos desprendidos durante o aquecimento. / The LnL3•2H2O compounds, where Ln represents the trivalent lanthanides (La to Lu) and yttrium (Y), and L represents nicotinate (C6H4NO2--) were synthesized. The synthesis was perfomed by addition of nicotinic acid lanthanides and yttrium carbonates, with stirring and heating. The characterization of the compounds in the solid state was carried out using the techniques of X-ray diffraction powder pattern, complexometry, infrared spectroscopy (FTIR) and by thermoanalytical techniques: simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC), differential scanning calorimetry (DSC), evolved gas analysises (EGA) by infrared spectroscopy (EGA: TG-FTIR) and thermalmicroscopy.The results provided information on the thermal behavior of the studied as compounds stoichiometry, crystallinity, coordination sites. It was also possible to identify the main gaseous products evolued during heating. / CNPq: 141952/2013-0
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Avaliação de emulsificante baseado na borra de óleo de soja para fluidos de perfuração sintéticos.LEAL, Caline Alves. 22 June 2018 (has links)
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Previous issue date: 2018-06-21 / CNPq / Este trabalho visa avaliar o desempenho de um emulsificante baseado na borra de
óleo de soja (EBO) para fluido de perfuração sintético a base de n-parafina. O
estudo do emulsificante foi realizado em três etapas distintas: na primeira, a
caracterização do emulsificante por meio dos ensaios de ATG, DTA e FTIR; na
segunda, a avaliação do emulsificante de acordo com a norma EP-1EP-00028-A da
Petrobras e, a terceira e última etapa, dedicada a avaliação do emulsificante em
formulações da indústria, por meio das propriedades reológicas (viscosidade
aparente (VA), viscosidade plástica (VP), limite de escoamento (LE) e força gel
(FG)), a estabilidade elétrica (EE) e o volume de filtrado HPHT (VF). A partir dos
resultados obtidos pode-se concluir que: o emulsificante obtido a partir da borra do
óleo de soja (EBO) é formado a partir de ácidos graxos com ligações dos tipos C-H,
C-O, C=O e C=C, com picos de intensidades e posições semelhantes ao óleo de
soja puro, apresentando três etapas de decomposição térmica: a primeira referente a
perda de material volátil, a segunda a matéria carbonosa e a terceira a
decomposição térmica do EBO; a borra de óleo de soja pode ser utilizada como
emulsificante primário para fluidos de perfuração sintético e, por fim, que o
emulsificante EBO apresentou maior eficiência nas propriedades reológicas (VA,
VP, LE e FG) e de filtração (VF) para fluidos sintéticos com razão óleo água 60/40.
No entanto, quando se trata da EE os melhores resultados foram obtidos para
fluidos com razão óleo água 70/30. / This study aimed to evaluate the performance of an emulsifier based on soybean oil
sludge (EBO) in synthetic drilling fluid to n-paraffin base. The study of the emulsifier
was conducted in three distinct stages: first, the characterization of the emulsifier
through the TGA , DTA and FTIR tests; second, the evaluation of the emulsifier
according to the standard EP-1EP-00028-Petrobras norm; and the third and last
stage, the evaluation of the emulsifier according to the industry formulations which
were evaluated by the rheological properties (apparent viscosities (AV), plastic
viscosity (PV), yield limit (YL) and gel strength (GS)), the electrical stability (ES) and
the filtrate volume HPHT (VF). From the results obtained it can be concluded that: the
emulsifier obtained from soybean oil sludge (EBO) is formed from fatty acids with HC, C-O, C = O and C = C bond types, with peaks intensities and positions similar to
pure soybean oil, with three-step thermal decomposition: The First Regarding Volatil
loss material, the second carbonaceous matter ea Third thermal decomposition do
EBO. Soybean oil sludge can be used as a primary emulsifier for synthetic drilling
fluids and finally the EBO emulsifier with highest efficiency rheological properties (AV,
PV, YL and GS) and filtering (FV) or synthetic fluids with water oil ratio 60/40.
However, when it comes EE best results were obtained with a ratio of oil to water
fluid 70/30.
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