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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Desenvolvimento de procedimentos analíticos limpos em sistemas de análises em fluxo para determinação de espécies de interesse ambiental / Development of clean analytical procedures in flow injection analysis for determination of environmentally relevant species

Wanessa Roberto Melchert 01 April 2005 (has links)
A química limpa tem como principal objetivo o desenvolvimento e a implementação de processos e produtos químicos para reduzir ou eliminar o uso ou a geração de substâncias nocivas à saúde humana e ao meio ambiente. Neste trabalho, foram desenvolvidos procedimentos analíticos limpos para a determinação de nitrato e nitrito em águas naturais e para o tratamento dos resíduos gerados na determinação espectrofotométrica de nitrito e fenóis. Para tanto, foram exploradas as principais estratégias empregadas em química limpa: substituição dos reagentes tóxicos, minimização do consumo dos reagentes e dos resíduos gerados e tratamento desses resíduos. O procedimento analítico limpo para a determinação de nitrato em águas naturais foi baseado em medidas diretas no ultravioleta, após separação de nitrato dos interferentes utilizando um sistema de análises em fluxo com coluna de resina aniônica. O método desenvolvido emprega um único reagente (HClO4) em quantidades mínimas (18 µL/determinação) e permite a determinação de nitrato entre 0,50 e 25,0 mg L-1, sem interferência de ácido húmico, NO2-, PO43-, Cl-, SO42- e ferro(III) nas quantidades usuais em águas naturais. A freqüência de amostragem e o coeficiente de variação (n = 20) foram estimados em 17 determinações h-1 e 0,7%, respectivamente. Os resultados obtidos para amostras de águas de diferentes procedências foram concordantes com o método de referência (redução a nitrito por limalhas de cádmio cobreado seguida por reação de diazo-acoplamento) a nível de confiança de 95%. O tratamento do resíduo gerado na determinação de nitrito, empregando irradiação (UV) na presença do reagente de Fenton (80 mmol/L H2O2 e 1 mmol/L Fe2+), promoveu completa descoloração do resíduo com diminuição de ca. 87% na concentração de carbono orgânico total. A fotodegradação também foi aplicada no tratamento do resíduo gerado na determinação de fenóis totais com 4-aminoantipirina. A degradação ocorreu na presença de H2O2 e irradiação (UV). A completa supressão da absorção de radiação pela 4-aminoantipirina foi observada após 30 min de recirculação da solução no foto-reator, à vazão de 4 mL/min. O procedimento analítico para a determinação de nitrito foi baseado em sistema de análises em fluxo com multicomutação empregando mini-bombas solenóides para o gerenciamento das soluções. O sistema foi acoplado a um foto-reator para a degradação em linha dos resíduos gerados. O método desenvolvido minimiza as quantidades de reagentes (0,6 mg sulfanilamida e 0,03 mg N-naftil-etilenodiamina por determinação) e permite a determinação de nitrito entre 0,10 e 1,00 mg L-1 (r = 0,998) com sensibilidade comparável à alcançada no procedimento com adição contínua de reagentes. O limite de detecção (99,7% de confiança), coeficiente de variação (n = 20) e freqüência de amostragem foram estimados em 17 µg L-1, 2,6% e 80 determinações h-1, respectivamente. / Green chemistry has as principal objective the development and implementation of chemical processes and products to minimize or eliminate the use or generation of harmful substances to the human health and the environment. In this work, clean analytical procedures for determination of nitrate and nitrite in natural waters and for the treatment of wastes generated in the spectrophotometric determination of nitrite and phenol were developed. The principal strategies employed in green chemistry were explored to achieve these goals: replacement of the toxic reagents, minimization of reagent consumption and waste generation and waste treatment. The clean analytical procedure for nitrate determination in natural waters was based on the direct spectrophotometric measurement in the ultraviolet, after separation of nitrate from interfering species in a flow-injection system with an anion-exchange resin. The developed method employ only one reagent (HClO4) in minimum amount (18 µL/determination) and can be applied for nitrate determination within 0.50 and 25.0 mg L-1, without interference of humic acid, NO2-, PO43-, Cl-, SO42- and iron(III) in concentrations typically found in natural waters. The sampling rate and the coefficient of variation (n = 20) were estimated as 17 determinations per hour and 0.7%, respectively. Results obtained for natural water samples of different origin were in agreement with the reference method (reduction to nitrite by copperized cadmium filings followed by a diazo-coupling reaction) at the 95% confidence level. The treatment of the waste generated in nitrite determination employing UV irradiation in the presence of Fenton reagent (80 mmol/L H2O2 and 1 mmol/L Fe2+) caused the complete discoloration of the waste and reduced the total organic carbon concentration in 87%. The photodegradation was also applied for the treatment of the waste generated in the determination of total phenols with 4-aminoantipyrine. The degradation occurred in the presence of H2O2 and UV irradiation. Radiation absorption by 4-aminoantipyrine was completely suppressed after 30 min of treatment of solution in the recirculation mode at 4mL/min. The analytical procedure for nitrite determination was based on a flow system with multicommutation employing solenoid micro-pumps for the solution handling. The developed method minimizes the reagent amounts (0.6 mg sulfanilamide and 0.03 mg N-(1-Naphthyl)-ethylene-diamine per determination) and can be applied for nitrite determination within 0.10 and 1.00 mg L-1 (r = 0.998) with sensitivity comparable to the achieved in the procedure with continuous reagent addition. The detection limit (99.7% of confidence), coefficient of variation (n = 20) and sampling rate were estimated as 17 µg L-1, 2.6% and 80 determinations per hour, respectively.
82

Desenvolvimento de procedimentos limpos para extração de íons metálicos em ponto nuvem / Development of green analytical procedures for cloud-point extraction of metal ions

Sidnei Gonçalves da Silva 28 February 2008 (has links)
O presente trabalho enfoca o desenvolvimento de procedimentos analíticos limpos através da extração e pré-concentração de íons metálicos em ponto nuvem para aumento de sensibilidade, melhoria de seletividade e substituição de solventes tóxicos. Cobre(II), ferro(II) e níquel(II) foram extraídos simultaneamente em digeridos de materiais vegetais, utilizando como agente extrator o Triton X-114, após formarem complexos hidrofóbicos com o 1,2-tiazolilazo-2-naftol (TAN). Os analitos foram determinados por espectrometria de absorção atômica com chama (Cu, Fe e Ni) ou por espectrofotometria de absorção molecular (Fe). A determinação de Cu e Ni por espectrofotometria de absorção molecular foi inviabilizada por interferências espectrais causadas pela formação de complexos com diversos íons metálicos encontrados nos digeridos dos materiais vegetais. Nas medidas por FAAS, os limites de detecção (99,7 % de confiança) foram estimados em 1,10 e 5 µg L-1 para cobre, ferro e níquel, respectivamente. Respostas lineares foram observadas para cobre e ferro na faixa de concentração de 25-200 µg L-1 e para o níquel entre 5 e 80 µg L-1 . O fator de enriquecimento foi estimado em 30 e a extração dos analitos foi quantitativa, de acordo com medidas efetuadas no sobrenadante após extração. Na determinação de ferro por espectrofotometria de absorção molecular, o limite de detecção foi estimado em 1 µg L-1 , com resposta linear entre 6 e 60 µg L-1 e fator de enriquecimento estimado em 20. Após digestão com ácidos diluídos em forno de microondas, o procedimento proposto foi aplicado à determinação dos analitos em digeridos de materiais de referência certificados, sendo os resultados concordantes com os valores certificados a nível de confiança de 95 %. O consumo de reagentes foi estimado em 50 mg Triton X-114 e 150 µg TAN por determinação. / This work is focused on the development of green analytical procedures for cloud-point extraction and concentration of metal ions, aiming increasing sensitivity, improving selectivity and avoiding the use of toxic solvents. Copper(II), iron(II) and nickel(II) were simultaneously extracted from plant materials digests, by using Triton X-114 as extracting agent, after formation of hydrophobic complexes with 1,2- tiazolylazo-2-naphthol (TAN). The analytes were determined by flame atomic absorption spectrometry (Cu, Fe and Ni) or by molecular absorption spectrophotometry (Fe). The determination of Cu and Ni by UV-vis spectrophotometry was hindered by spectral interferences caused by the formation of complexes with several metal ions in the sample digests. In the measurements by FAAS, the detection limits (99.7 % confidence level) were estimated as 1, 10 and 5 µg L-1 for copper, iron and nickel, respectively. Linear responses were observed in the 25-200 µg L-1 range for copper and iron and 5-80 µg L-1 for nickel. The enrichment factor was estimated as 30 and the extraction was quantitative, as evaluated by measurements in the supernatant solution after extraction. For iron determination by UV-vis spectrophotometry, the detection limit was estimated as 1 µg L-1 , with linear response within 6 and 60 µg L-1 and enrichment factor of 20. After digestion with diluted acids in microwave oven, the procedure was applied to the determination of the metals in reference materials and the results agreed with the certified values at the 95 % confidence level. The reagent consumption was estimated as 50 mg Triton X-114 and 150 µg TAN per determination.
83

Estudo de método alternativo para determinação da demanda química de oxigênio (DQO) por meio de eletrodo Cu/CuO / Study of alternative method for chemical oxygen demand (COD) by Cu / CuO electrode

Valerio, Daniele Cerri 22 March 2018 (has links)
Submitted by Marilene Donadel (marilene.donadel@unioeste.br) on 2018-06-07T17:55:09Z No. of bitstreams: 1 Daniele_Valerio_2018.pdf: 1646287 bytes, checksum: 5865f9a0bcde43e1b44aa8bd450448e8 (MD5) / Made available in DSpace on 2018-06-07T17:55:10Z (GMT). No. of bitstreams: 1 Daniele_Valerio_2018.pdf: 1646287 bytes, checksum: 5865f9a0bcde43e1b44aa8bd450448e8 (MD5) Previous issue date: 2018-03-22 / In function of the growing demand for activities that minimize the impacts environmental created by waste, the effluent analysis are extremely important to determine the intensity of contamination in water bodies. Due to the large part these effluents have materials rich in nutrients, with C, N e P and others organics and inorganics components, it is used to determination the chemical oxygen demand (COD), methodology used to measure the amount of oxygen consumed by certain substances. In this context, the objective of this study was to develop electrochemical method to determination the Chemical Oxygen Demand using copper electrode. The electrode was prepared using accessible chemical reagents and in small quantities. By means of measures electrochemical the performance test was performed using glucose. The obtained results demonstrated the formation of a cooper oxide layer that allows the electrode application, whereas, the copper oxidizes organic compounds in alkaline medium, such as carbohydrates. Performing the repeatability test using standard glucose solution, the method accuracy was 2.13% and a detection limit of 146 mg L-1. It was possible to compare the fructose, sucrose and sorbitol compounds in order to evaluate the copper electrode answer by the cyclic voltammetry in the same experimental conditions for glucose. The Cu / CuO electrode presents satisfactory analytical response that was used to study chemical oxygen demand by addition of standard, comparing with the official method. However, because the values found in the samples by the official method were below the value of the recommended range for the analytical range, the results dispersion (RSD) among others, it was not possible to correlate the methods. / Em função da crescente demanda por atividades que minimizem os impactos ambientais gerados por resíduos, as análises de efluentes são extremamente importantes para determinar a intensidade de contaminação em corpos hídricos. Devido à grande parte desses efluentes possuírem materiais ricos em nutrientes, como C, N e P e outros componentes orgânicos e inorgânicos, a determinação da demanda química de oxigênio (DQO), é a metodologia mais utilizada para medir a quantidade de oxigênio consumido por determinadas substâncias. Neste contexto, o objetivo do presente trabalho foi desenvolver método eletroquímico para a determinação da Demanda Química de Oxigênio utilizando eletrodo de cobre. O eletrodo foi preparado utilizando reagentes químicos de baixo custo e em pequenas quantidades e submetido a teste de desempenho utilizando glicose, por meio de medidas eletroquímicas. Os resultados obtidos demonstraram a formação de uma camada de óxido de cobre que permite a aplicação do eletrodo, visto que, o cobre em meio alcalino oxida compostos orgânicos, como os carboidratos. Realizando o teste de repetitividade utilizando solução padrão de glicose, obteve-se a precisão do método de 2,13% e um limite de detecção de 146 mg L-1. Foi possível comparar os compostos frutose, sacarose e sorbitol a fim de avaliar a resposta do eletrodo de cobre por meio de voltametria cíclica nas mesmas condições experimentais para a glicose. O eletrodo Cu/CuO apresenta resposta analitica satisfatoria que foi utilizada para estudo de demanda quimica de oxigenio por adição de padrão, comparando-se com o metodo oficial. Contudo, devido aos valores encontrados nas amostras pelo metodo oficial serem abaixo do valor da faixa recomendada para a faixa analitica, à dispersão dos resultados (RSD) entre outros, não foi possível correlacionar os métodos.
84

Preparation and characterization of some ionic liquids and their use in the dimerization reaction of 2-methylpropene

Kärkkäinen, J. (Johanna) 27 February 2007 (has links)
Abstract This study concentrates on the preparation and characterization of some ionic liquids and their use in dimerization reaction of 2-methylpropene. Ionic liquids consist of cations and anions, and are commonly understood as green solvents. By definition their melting points should be lower than 100 °C. Prepared ionic liquids were used as catalytic solvents in dimerizations of 2-methylpropene to a high octane compound, isooctene. The monograph consists of two parts: the literature survey and the practical work. The literature survey reviews the preparation and characterization of ionic liquids as well as their environmental aspects, such as toxicity, biodegradability and recyclability. In addition, the acid catalyzed dimerization of butenes is discussed together with the dimerizations of light olefins carried out in ionic liquids. The practical work consists of three entities: The environmentally benign preparation of 1-alkyl-3-methylimidazolium-based ionic liquids under microwave activation, the characterization of ionic liquids and the use of the ionic liquids in the dimerization reaction. Ionic liquids absorb efficiently microwave irradiation and the most beneficial aspect in the microwave-assisted preparations was the considerably shortened reaction time compared to the conventional methods. In addition to the microwave-assisted preparations, [Cnmim][InCl4] ionic liquids were prepared successfully without microwave irradiation. A special attention was paid to the characterization of ionic liquids since impurities are known to affect on the properties of the ionic liquids. Ionic liquids were analysed with the following methods: 1H and 13C NMR, MS(ESI+ and ESI-), GC and elemental analysis. Characterization of ionic liquids was done by determining the thermal stability, the melting point and the crystal structure of each solid ionic liquid. The determination of the liquid range of ionic liquid is necessary in order to know the temperature limits for each ionic liquid. Novel InCl3-based ionic liquids revealed to be the more efficient than Brønsted acidic ILs as a catalytic reaction media in the dimerization of 2-methylpropene. It was preferable to apply [C6mim]Cl/InCl3 (x(InCl3) = 0.55) as a catalytic IL since then the conversion of 2-methylpropene and the product distribution revealed to be good. In order to maximize the production and the separation of dimers reaction should be carried out continuously at temperature high enough, such as 160 °C. Neutral InCl3-based ionic liquid did not catalyze reaction of 2-methylpropene, but it had to be acidic x(InCl3) > 0.5. Excess of InCl3 did not leach out from the IL and the recycling of IL was possible.
85

Well-defined iron and manganese catalysts for reduction and dehydrogenation reactions / Catalyseurs bien définis de fer et de manganèse pour des réactions de réductions et de déshydrogénation

Elangovan, Saravanakumar 19 January 2017 (has links)
La substitution des métaux nobles par des métaux de transition abondants et bon marché est un challenge majeur de ce siècle en chimie de synthèse. Récemment, les métaux abondants tels que le fer et le manganèse (1er et 3ème en abondance dans l'écorce terrestre) ont connu un essor remarquable en catalyse homogène, notamment en réduction. Les travaux de thèse ont portés sur le développement de nouveaux catalyseurs bien-définis efficaces du fer et du manganèse pour effectuer des réactions d'hydrogénation de dérivés carboxyliques, de réduction par prêt d'hydrogène et de déshydratation d'amides. / The substitution of noble metals by abundant and cheap transition metals is a major challenge of this century in synthetic chemistry. Recently, abundant metals such as iron and manganese (1st and 3rd in abundance in the Earth's crust) have seen remarkable growth in homogeneous catalysis, especially in reduction. The thesis work focused on the development of new well-defined efficient catalysts of iron and manganese to carry out reactions of hydrogenation of carboxylic derivatives, reduction by hydrogen and dehydration of amides.
86

Emergency Preparation and Green Engineering Tool

Whiteley, Clinton E January 1900 (has links)
Master of Science / Department of Chemical Engineering / Larry E. Erickson / As our society continues to better prepare itself to address biological, radiological, chemical, and environmental emergencies, there is a need for better and more readily available emergency planning information for program managers and military/business personnel. An online hazardous materials and emergency planning tool for the Environmental Knowledge and Assessment Tool (EKAT: www.ekat-tool.com) would adequately fill that need. The proposed online Emergency Preparation and Green Engineering (EPGE) tool would provide the user with information regarding links to local emergency response teams and resources, guides for developing emergency plans and reports, Hazardous Materials (HAZMAT) training information, case studies to illustrate HAZMAT situations, and the ability to judge the environmental friendliness of chemicals. In this way it will serve as a means of facilitating and educating individuals for best responses in an organized fashion. In order to address their environmental responsibilities, public and private organizations are adopting Environmental Management Systems (EMS). The EPGE tool can be used in conjunction with Environmental Management Systems (EMS) to begin to address sustainability in a more practical setting. Currently the development of a comprehensive tool that identifies environmental, health, and safety concerns along with supplying relevant emergency data would be applicable to any business or organization. This tool will be available as an initial building block for the sustainability of the company. It can be used as a guide to better characterize and solve the environmental issues that could affect any business.
87

Dehydration in aqueous media / Déshydradation en milieux aqueux

Le Guenic, Sarah 01 December 2015 (has links)
Les années 1990 ont été marquées par le développement de la Chimie Verte avec les premiers travaux sur le sujet et l’introduction des Douze Principes. Depuis, le nombre de recherches sur la Chimie Verte n’a cessé de croître. Ces travaux de thèse portent sur le développement de méthodes de déshydratation dans le but de former des molécules à haute valeur ajoutée en utilisant les Douze Principes de la Chimie Verte en tant que ligne directrice. Deux molécules cibles ont été sélectionnées : (i) le phénylacétaldéhyde, obtenu par déshydratation du 1-phényléthane-1,2-diol, qui est utilisé dans la composition de parfums, de médicaments, d’insecticides, etc., ou en tant qu’intermédiaire réactionnel ; et (ii) le furfural, formé par la triple déshydratation du D-xylose (monomère principal des hémicelluloses), qui peut être utilisé comme solvant sélectif ou comme molécule plateforme pour produire une large gamme de composés d’intérêt. Plusieurs points-clés ont été identifiés pour concevoir des procédés de déshydratation verts: le solvant (l’eau ou le solvant éco-compatible CPME), la méthode d’activation (utilisation d’irradiation micro-ondes ou d’un réacteur en flux continu) et le catalyseur (chlorures de métaux ou résine échangeuse d’ions). / The 1990s have witnessed the development of Green Chemistry with the first researches on the subject and the introduction of the Twelve Principles. Since then, the number of scientific works on Green Chemistry has continuously grown. This PhD work focus on the development of dehydration methods to form high added value molecules by using the Twelve Principles of Green Chemistry as a guiding framework. Two target molecules were selected: (i) phenylacetaldehyde, obtained by the dehydration 1-phenylethane-1,2-diol, which is used in perfume compositions, for the preparation of pharmaceuticals, insecticides, etc., or as a chemical intermediate; and (ii) furfural, formed thanks to the triple dehydration of D-xylose (the main sugar unit of hemicellulose), which can be used as a selective solvent or as a platform molecule to produce a wide range of high-value chemicals. The optimisation of green production processes was focused on several key points: solvents (water and the eco-friendly CPME), activation method (microwave irradiation and continuous flow) and catalysis (metal chlorides and ion-exchange resin).
88

Indium complexes and their role in the ring-opening polymerization of lactide

Douglas, Amy Frances 05 1900 (has links)
The synthesis and characterization of a series of chiral indium complexes bearing a tridentate NNO ligand are reported. The ligand 2-[[[(dimethylamino)cyclohexyl]amino]methyl]- 4,6-bis(tert-butyl) phenol (H₂NNO) was synthesized via a previously published procedure and bound to indium by both a protonolysis and salt metathesis route. A dimethylated indium complex (NNO)InMe₂ (1) was isolated by reaction of InMe₃ with H₂NNO. A one-pot saltmetathesis route was used to produce a unique mixed-bridge dinuclear indium complex [(NNO)InCl] ₂(μ-OEt)(μ-Cl) (3) from a mixture of indium trichloride, potassium ethoxide and the monopotassiated salt of the ligand, KH(NNO). Direct reaction of KH(NNO) and indium trichloride resulted in the formation of (NNO)InCl₂ (4) which was carried forward to 3 by reaction with sodium ethoxide. The complex 3 is active for the ROP of β-butyrolactone ε-caprolactone and lactide and is the first reported indium-based catalyst for lactide or β-butyrolactone ROP. Kinetic studies of 3 for ROP of LA revealed that catalyst was well-behaved, and that the rate was first order with regard to lactide and catalyst. The enthalpy and entropy of activation for the ROP were experimentally determined. Polymer produced by ROP by 3 has narrow molecular weight distribution and a good correlation is seen between the observed moleular weight and monomer loading. A mechanism was proposed for 3 acting as a catalyst for the ROP of lactide; however further experiments are required to confirm this mechanism. Polymer samples isolated from the ROP of rac-lactide by rac-3 show isotactic enrichment. It is postulated that the chiral catalyst 3 is exerting stereocontrol via an enantiomorphic site control mechanism. / Science, Faculty of / Chemistry, Department of / Graduate
89

Amine Transaminases in Multi-Step One-Pot Reactions

Anderson, Mattias January 2017 (has links)
Amine transaminases are enzymes that catalyze the mild and selective formation of primary amines, which are useful building blocks for biologically active compounds and natural products. In order to make the production of these kinds of compounds more efficient from both a practical and an environmental point of view, amine transaminases were incorporated into multi-step one-pot reactions. With this kind of methodology there is no need for isolation of intermediates, and thus unnecessary work-up steps can be omitted and formation of waste is prevented. Amine transaminases were successfully combined with other enzymes for multi-step synthesis of valuable products: With ketoreductases all four diastereomers of a 1,3-amino alcohol could be obtained, and the use of a lipase allowed for the synthesis of natural products in the form of capsaicinoids. Amine transaminases were also successfully combined with metal catalysts based on palladium or copper. This methodology allowed for the amination of alcohols and the synthesis of chiral amines such as the pharmaceutical compound Rivastigmine. These examples show that the use of amine transaminases in multi-step one-pot reactions is possible, and hopefully this concept can be further developed and applied to make industrial processes more sustainable and efficient in the future. / <p>QC 20170113</p>
90

Celulose e lignocelulósicos como suportes na remoção de contaminantes em líquidos / Cellulose and lignocellulosics as supports toward contaminants removal from liquids

Melo, Julio Cesar Perin de, 1982- 12 November 2012 (has links)
Orientador: Claudio Airoldi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-22T05:25:35Z (GMT). No. of bitstreams: 1 Melo_JulioCesarPerinde_D.pdf: 28431838 bytes, checksum: 0460daaa92bb9d6b56903affddf613c8 (MD5) Previous issue date: 2012 / Resumo: O trabalho foi realizado com biopolímeros orgânicos naturais: celulose e lignocelulósicos, modificados quimicamente aumentando a capacidade de sorção de contaminantes em líquidos. Foram caracterizados por IV, RMN de C, DRX, MEV and TG. Assim, as inércias química e física foram superadas através dos seguintes procedimentos sintéticos: esterificação com anidridos de celulose (maleato: 2,82, succinato: 3,07, ftalato: 2,99 mmol g) e de mesocarpo de babaçu (maleato: 141,79, succinato:176,99, ftalato:149,27 mg g); cloração da celulose com cloreto de tionila (4,95 mmol g); aminação de celulose com etileno-1,2-diamina (3,03 mmol g); reação de etilenossulfeto com mesocarpo (86,7 mg g) e epicarpo de babaçu (20,2 mg g). Com as modificações químicas dos biopolímeros as propriedades de sorção se tornaram superiores as dos biopolímeros de partida e as novas capacidades máximas de remoção de contaminantes foram: anidridos de celulose [maleato (Ni = 1,75 e Co = 2,40 mmol g), succinato: (Ni = 2,46 e Co = 2,46 mmol g) e ftalato: (Ni = 2,26 e Co = 2,43 mmol g)]; anidridos com mesocarpo de babaçu (maleato: (Cu = 19,88 mg g), succinato: (Cu = 38,58 mg g) e ftalato: (Cu = 30,63 mg g) soluções hidroalcoólicas); aminação de celulose com etileno-1,2-diamina (Cu = 2,32, Co = 1,35, Ni= 1,70 e Zn = 1,65 mmol g); reação de etilenossulfeto com mesocarpo (Cu = 39,6 mg g) e epicarpo (Cu = 39,2 mg g) de babaçu. A celulose também foi oxidada com metaperiodato aquoso para dar origem à celulose em sua forma oxidada, o 2,3-dialdeídocelulose, material de partida para outras reações, as quais foram: redução dos grupos aldeído do 2,3-dialdeídocelulose, seguido da reação deste material com os anidridos malêico, succínico e ftálico; em seguida cada um dos materiais na forma ácida foi reagido separadamente com etileno-1,2-diamina, dietil-1,2,4-triamina, trietil-1,2,4,6-tetramina. A outra rota foi a reação do 2,3-dialdeído-celulose com as poliaminas etileno-1,2-diamina, dietil-1,2,4-triamina, trietil-1,2,4,6-tetramina e em seguida, com cada um dos materiais aminados obtidos, reagí-los separadamente com os anidridos malêico, succínico e ftálico. / Abstract: The natural organic biopolymers, cellulose and lignocellulosics, were chemically modified in order to increase their sorption capacities for contaminants from liquids. The technics employed for characterization were IR, C NMR, XDR, SEM and TGA. Chemical modification and the degree of substitution were: esterification of cellulose with anhydrides [maleate: 2,82 mmol g, succinate: 3,07 mmol g, phthalate: 2,99 mmol g) and esterification of babassu mesocarp coconut with anhydrides (maleate: 141,79 mg g, succinate: 176,99 mg g, phthalato: 149,27 mg g); chlorination of cellulose with thionyl chloride (4,95 mmol g); amination of cellulose with ethylene-1,2-diamine (3,03 mmol g); reaction of ethylenesulfide with babaçu coconut mesocarp (86,7 mg g) and epicarp (20,2 mg g) The sorption capacities of these chemically modified biopolymers were outlighted as confirmed by the maxima sorption results and were: cellulose with anhydrides (maleate: (Ni = 1,75 e Co = 2,40 mmol g), succinate: (Ni = 2,46 e Co= 2,46 mmol g) e ftalate: (Ni = 2,26 e Co = 2,43 mmol g)); babassu mesocarp coconut with anhydrides [maleate: (Cu = 19,88 mg g), succinate: (Cu = 38,58 mg g) e ftalate: (Cu = 30,63 mg g) hydroalcoholic solution]; aminated cellulose (Cu = 2,32, Co = 1,35, Ni = 1,70 e Zn = 1,65 mmol g); babaçu coconut thyol-mesocarp (Cu = 39,6 mg g) e epicarp (Cu = 39,2 mg g). Cellulose was also oxidized with aqueous methaperiodate to produce cellulose-2,3-dialdehyde, which was used in other reactions: reduction of aldehyde groups, followed by reacting it with maleic, succinic and phthalic anhydrides; each of these materials in their acid form was reacted with ethylene-1,2-diamine, diethyl-1,2,4-triamine, triethyl-1,2,4,6-tetramine. The 2,3-dialdehyde-cellulose was also reacted with ethylene-1,2-diamine, diethyl-1,2,4-triamine, triethyl-1,2,4,6-tetramine and the aminated cellulose was separately reacted with maleic, succinic and phthalic anhydrides. / Doutorado / Quimica Inorganica / Doutor em Ciências

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