Profenofós é um organofosforado empregado como inseticida e acaricida amplamente utilizado no Brasil para o controle de pragas de cebolas, milho, soja, café, tomate, algodão, feijão, batata e outros. A irradiação é um processo empregado em todo o mundo e recomendada por diversos órgãos de saúde para a conservação de alimentos. A radiação ionizante utiliza raios gama, raios X ou aceleradores de elétrons e tem sido aplicada para eliminar ou reduzir a ação de agentes patogênicos e contribuir para aumentar o tempo de estocagem de vários alimentos. Os objetivos desse trabalho foram: (a) avaliar a degradação de soluções aquosas de profenofós submetidas à radiação ionizante, identificar e quantificar a formação de novos produtos por GC-MS; (b) analisar o efeito de feixe de elétrons em ervilhas inoculadas com soluções aquosas de profenofós; (c) sintetizar Polímeros Molecularmente Impressos (MIP) e Sílica Impressa Molecularmente (MIS), posteriormente, caracterizar os adsorventes em fase sólida e verificar sua seletividade para profenofós. O tratamento com aceleradores de elétrons com dose 31,6 kGy promoveu a formação de um novo produto de degradação e redução de 93,40 % de profenofós em soluções aquosas. Em ervilhas inoculadas com 1 μg de profenofós submetidas à radiação ionizante de 30,4 kGy promoveu uma redução na concentração de profenofós em 57,46 %. Além disso, foram realizadas sínteses de MIP e MIS para a extração em fase sólida de profenofós. Os MIS sintetizados por sol-gel mostraram-se eficazes para o reconhecimento molecular e extração seletiva de profenofós. / Profenofos is an organophosphate widely used in Brazil as insecticide and acaricide in the control of pests in onions, corn, soybeans, coffee, tomato, cotton, beans, potatoes among others. Irradiation is a process used worldwide and recommended by many health agencies for food preservation. Food irradiation preserving process uses accelerated electrons, gamma rays or X-rays. Ionizing radiation treatment is applied to eliminate or to reduce the action of pathogens and to increase the shelf life of some foods. The objective of this study were (a) to evaluate the degradation of aqueous solutions of Profenofos by ionizing radiation, identify and quantify the formation of new products by GC-MS; (b) to analyze the effects of electron beam in peas inoculated with aqueous solutions of Profenofos; (c) to synthesize Molecularly Imprinted Polymer (MIP) and Molecularly Imprinted Silica (MIS), subsequently characterize the adsorbents in solid phase and check its selectivity for profenofos. The treatment with electron accelerators with 31.6 kGy dose promoted the formation of a new by-product and 93.40 % reduction of profenofos in aqueous solutions. In peas inoculated with 1 μg of profenofos by ionizing radiation of 30.4 kGy promoted a reduction of 57.46 % in the concentration of profenofos. Furthermore, the MIP and MIS were performed for solid phase extraction of profenofos. The MIS synthesized by sol-gel proved to be effective for the recognition molecular and selective extraction of profenofos.

A lamotrigina (LTG) é um fármaco pertencente à classe das feniltriazinas utilizado no tratamento de crises epilépticas generalizadas e focais e no tratamento adjunto da epilepsia refratária. Devido à alta variabilidade interindividual, às interações medicamentosas e aos efeitos adversos apresentados durante a administração da LTG, a monitorização terapêutica nos pacientes que fazem uso deste fármaco é necessária para ajuste de dose individual e evitar os efeitos adversos. Assim, o objetivo deste trabalho foi a avaliação de duas técnicas de microextração: a microextração em fase líquida com fibras ocas (HF-LPME) e a microextração líquido-líquido dispersiva (DLLME) para análise da lamotrigina em amostras de plasma de pacientes epilépticos. Primeiramente foram definidas as condições eletroforéticas: foi utilizado um capilar de sílica fundida de 75 ?m de diâmetro interno e 50 cm de comprimento efetivo. O eletrólito de corrida (BGE) foi composto por ácido 2-morfolinoetanosulfônico (MES), na concentração de 130 mmol L-1 e pH 5,0. As análises foram realizadas à temperatura de 20°C e tensão de 15 kV. A amostra foi injetada hidrodinamicamente (0,5 psi por 10 s) e a detecção foi feita em 214 nm. Nestas condições a LTG e o padrão interno (PI), lidocaína, puderam ser analisados em menos de 7 minutos. A HF-LPME foi avaliada no modo de 3 fases, usando 500 ?L de plasma e 3,5 mL de solução fosfato de sódio 50 mmol L-1 pH 9,0 como fase doadora. O solvente utilizado para impregnar a fibra foi o 1-octanol. Como fase aceptora foram utilizados 60 ?L de solução de ácido clorídrico pH 4,0. Para avaliação da DLLME, foi necessária uma etapa de pré-tratamento da amostra (500 ?L de plasma) com 1 mL de acetonitrila. Após isto, 1,3 mL do sobrenadante foram adicionados a 4 mL de solução fosfato de sódio 50 mmol L-1 pH 9,0 e 120 ?L de clorofórmio (solvente extrator) foram injetados nesta amostra aquosa e 165 ?L de fase sedimentada foram recuperados. As características de desempenho analítico para ambos os métodos foram avaliadas, sendo obtida linearidade na faixa de concentração plasmática de 1-20 ?g/mL e limite inferior de quantificação (LIQ) de 1 ?g mL-1. Os ensaios de precisão e exatidão apresentaram valores de acordo com os guias oficiais. Além disso, os métodos foram seletivos, não apresentaram efeito residual e as amostras foram estáveis. Os valores de recuperação foram de 54,3 e 23% para HF-LPME e DLLME, respectivamente. Os métodos validados foram aplicados com sucesso em amostras de plasma de pacientes epilépticos em tratamento com a LTG. Além disso, as duas técnicas foram comparadas e a HF-LPME apresentou vantagens em relação à DLLME, mostrando ser uma técnica promissora para análise de matrizes complexas, com reduzido consumo de solvente orgânico e possibilidade de automação. / Lamotrigine (LTG) is an antiepileptic drug, which belongs to the class of phenyltriazine that can be used in the treatment of new-onset and refractory epilepsy. Due to its high interindividual variability, drug interactions and the adverse effects presented during the LTG administration, therapeutic drug monitoring is very important to dose adjustment and to avoid toxicity effects. Thus, the goal of this study was to develop and validate two microextraction techniques: the hollow fiber liquid-phase microextraction (HF-LPME) and the dispersive liquid-liquid microextraction (DLLME) to analyze LTG in plasma samples of epileptic patients. First of all, the eletroforetic conditions were optimized. A fused-silica uncoated capillary with 75 ?m internal diameter, and 50 cm effective length was used. The 2-(N-morpholino)ethanesulfonic acid (MES) 130 mmol L-1 pH 5.0 was chosen as background electrolyte (BGE). The temperature and the voltage were kept constant at 20°C and 15 kV respectively. For sample injection, hydrodynamic injection mode was used, with a pressure of 0.5 psi applied for 10 s. The wavelength was set at 214 nm. Under final conditions, LTG and the internal standard (IS) lidocaine were analyzed in less than 7 minutes. HF-LPME was evaluated in the three phase mode. The analyte was extracted from 4.0 mL of a basic donor phase (composed of 500 ?L of plasma and 3.5 mL of sodium phosphate solution 50 mmol L-1 pH 9.0) into an organic phase composed of 1-octanol immobilized in the pores of the hollow fiber, and further into an acidic acceptor phase (hydrochloric acid solution pH 4.0) placed in the lumen of the fiber. To evaluate DLLME, the plasma samples were pretreated to remove the proteins, and 500 ?L of plasma sample was mixed with 1 mL of acetonitrile. After that, 1,3 mL of the upper layer was added to 4 mL of sodium phosphate solution 50 mmol L-1 pH 9.0, and 120 ?L of chloroform (extracting solvent) was rapidly injected in the aqueous sample and 165 ?L of the sedimented phase was collected. Under the optimized conditions, both methods were linear over the plasmatic concentration range of 1.0-20.0 ?g mL-1 and the lower limit of quantification (LLOQ) was 1.0 ?g mL-1. Both methods showed good precision, accuracy, selectivity to LTG, with no carryover and the samples were stable under the studied conditions. The recovery were 54,3 and 23% to HF-LPME and DLLME respectively. The validated methods were successfully applied for the quantification of LTG in plasma samples of epileptic patients. The techniques were compared and HF-LPME was more advantageous for being more suitable to analysis of complex matrices using small amount of organic solvent, and also can be automated.

Das Ziel der vorliegenden Arbeit bestand in der Synthese von neuen funktionalisierten tripodalen Azaliganden auf Basis von Tris(2-aminoethyl)amin (Tren) und ihrer Charakterisierung als Rezeptoren und Extraktionsmittel für Kationen, Anionen sowie Salze. Die Komplexbildungs- und Phasentransfereigenschaften gegenüber den Kationen Ag(I), Co(II), Ni(II), Cu(II), Zn(II) und Cd(II) sowie den Anionen Cl-, Br-, I-, H2PO4-, SO42- und HCrO4- wurden durch Flüssig-Flüssig-Extraktion und Flüssigmembrantransport, 1H-NMR-Spektroskopie sowie Silberpotentiometrie untersucht; Struktur-Wirkungsbeziehungen für die jeweiligen Wirt/Gast-Systeme wurden abgeleitet. Röntgenkristallstrukturanalysen ausgewählter Komplexe mit den Kationen Ag(I), Ni(II) und Cu(II), den Anionen Br- und BF4- sowie dem Salz Hg(ClO4)2 ergänzten die gewonnenen Aussagen durch detaillierte Informationen zur Struktur und zu den auftretenden Wechselwirkungen. In die Betrachtungen wurden vergleichende Untersuchungen zur Ag(I)-Bindung durch strukturverwandte tripodale Schiffsche Basen einbezogen. Zusammenfassend wird der Einfluss der unterschiedlichen ligandspezifischen Charakteristika sowie der Substratspezies auf die Komplexbildung in Lösung und die Festkörperstruktur diskutiert. Die untersuchten tripodalen Aminverbindungen auf Basis von Tren zeigten in Abhängigkeit von ihrer Struktur ein differenziertes Extraktionsverhalten im System Metallsalz-Puffer-Wasser/Ligand-Chloroform. Als wesentliche Einflussfaktoren auf die Extraktion erwiesen sich Art, Anzahl und Anordnung der Donoratome sowie die differenzierte Lipophilie der Liganden. Die Zusammensetzung der extrahierten Komplexe in der organischen Phase ergab sich in den meisten Fällen zu 1:1 (Ag(I) : Ligand). Die bestimmte Reihe steigender Komplexstabilität für die 1:1-Komplexe von Ag(I) in Methanol unterstreicht in Analogie zu den Extraktionsuntersuchungen den Einfluss der Ligandcharakteristika auf die Komplexbildung. So führten Liganden mit tertiären Aminstickstoffatomen, zusätzlichen O-Donoratomen sowie sterisch anspruchsvollen Substituenten im Molekül zu geringeren Komplexstabilitäten, während zusätzliche S- und Pyridin-N-Donoratome in den untersuchten Aminverbindungen eine deutliche Steigerung der bestimmten Konstanten ergaben. Vergleichende Untersuchungen mit tripodalen Iminopodanden zeigten mit Ausnahme des 2-pyridylmethyl-substituierten Liganden generell niedrigere Stabilitäten der Ag(I)-Komplexe. 1H-NMR-Untersuchungen zur Komplexbildung in Lösung deuten unter veränderten Bedingungen auch auf einen möglichen Wechsel in der Komplexzusammensetzung und im Bindungsmuster für Ag(I) in Abhängigkeit von den im Molekül vorhandenen Donorfunktionen hin. Während für N4-Liganden ohne zusätzliche Donoratome sowie in Anwesenheit von S- und N-Donoratomen eine Zusammensetzung (Ag(I) : Ligand) von 1:1 bestimmt wurde, führen zusätzliche Pyridin-N-Donoratome zu einem stöchiometrischen Verhältnis von 3:2. Die Röntgenstrukturanalysen der Ag(I)-Komplexe von tripodalen Schiffschen Basen mit unterschiedlichen Substituenten unterstreichen die Variabilität der Koordinationsgeometrie von Ag(I) in Abhängigkeit vom Liganden. Interessant ist die Ausbildung von schwachen C-H···Ag-Wasserstoffbrücken in den Ag(I)-Komplexen der benzyl- und 4-biphenylmethyl-substituierten Liganden. Für die Kationen Co(II) und Zn(II) wurden mit den untersuchten Liganden generell nur geringe Extrahierbarkeiten erzielt. Dabei ist der Einfluss von Ligandstruktur sowie Lipophilie der Verbindungen auf die Extraktion stärker ausgeprägt als für Ag(I). Die Extraktion aus einem Gemisch von Co(II), Ni(II), Cu(II), Zn(II) und Cd(II) zeigte generell einen Anstieg der Extraktion in der Reihe Co(II) < Ni(II) < Zn(II) < Cd(II) < Cu(II). Lediglich die Verbindung mit einer OH-Funktion in 2-Position der aromatischen Substituenten führte zu höheren Extraktionsausbeuten für Co(II), Ni(II) und Cd(II) gegenüber Cu(II) und Zn(II). Röntgenstrukturanalysen von vier Cu(II)- bzw. Ni(II)-Komplexen veranschaulichen die bevorzugte höhere Koordinationszahl dieser Metallionen in relevanten Komplexen im Vergleich zu Ag(I). Die höhere Koordinationszahl wird dabei durch eine zusätzliche Koordination von Anionen oder Lösungsmittelmolekülen erreicht. Im Gegensatz zu den Kationen ist die Anionenextraktion wesentlich sensitiver gegenüber wechselnden experimentellen Bedingungen. Das hängt insbesondere mit den veränderten Bindungsverhältnissen in Anionenkomplexen zusammen. So wird die Extraktionsausbeute stark durch die Lipophilie der Liganden beeinflusst; ein signifikanter Anionentransport in die organische Phase wurde lediglich mit lipophilen Liganden erzielt. Die beobachtete Abstufung steigender Extraktion SO42- < Cl- < HCrO4- < I- ist in Übereinstimmung mit der zunehmenden Lipophilie dieser Anionen. In Abhängigkeit von der Natur der vorhandenen N-Donorfunktionen im Liganden und der Struktur der Liganden insgesamt wurde ein ausgeprägter pH-Einfluss auf die Extraktion der Anionen beobachtet. Während für die Liganden mit sekundären Aminfunktionen hohe Extrahierbarkeiten bei einem pH-Wert von ca. 5 auftraten, stiegen die Extraktionsausbeuten für Verbindungen mit tertiären Aminstickstofffunktionen mit abnehmenden pH-Wert kontinuierlich an. Die untersuchten Anionen wurden vorwiegend unter Bildung von 1:1- und 1:2-Komplexen (Anion : Ligand) in die organische Phase überführt. Für den Membrantransport war eine steigende Transportrate entsprechend der Dominanz der Lipophilie in der Reihe H2PO4- < SO42- < Cl- < Br- charakteristisch. Ein bevorzugter Transport von Cl- gegenüber Br- wurde hingegen mit sterisch anspruchsvollen Liganden sowie ausgeprägt lipophilen Verbindungen erreicht. Die Strukturen von zwei Anionenkomplexen mit BF4- bzw. Br- zeigen differenzierte Bindungsmuster. Einmal verhindern in einem Iminopodanden starke intramolekulare Wasserstoffbrücken zwischen dem protonierten Brückenstickstoff und den Iminfunktionen der Podandarme einen Einschluss des BF4--Anions in den vorliegenden Pseudokäfig, so dass die Koordination des Anions lediglich über schwache C-H···F-Kontakte an der Ligandperipherie erfolgt. Im Gegensatz dazu sind in einem N4-Aminliganden die drei Aminfunktionen der Podandarme protoniert. Die Br--Ionen werden sowohl durch ladungsunterstützte N-H···Br- als auch durch C-H···Br-Wasserstoffbrücken vom Liganden koordiniert. Weiterhin konnte in der Arbeit der Nachweis geführt werden, dass durch die Kombination von kationen- und anionenbindenden Funktionseinheiten in einem tripodalen Liganden die simultane Bindung und Extraktion von Kationen und Anionen möglich wird. Die Röntgenkristallstruktur eines Hg(ClO4)2-Komplexes bestätigt dabei die gleichzeitige Koordination von Kation und Anion durch die unterschiedlichen spezifischen Funktionseinheiten im Molekül.

In verfahrenstechnischen Anlagen der Flüssig-Flüssig-Stoffübertragung kommt es an der Phasengrenze zwischen den nicht mischbaren Flüssigphasen häufig zur Ausbildung hydrodynamischer Instabilitäten. Sie sind mit komplexen Geschwindigkeitsfeldern in den Flüssigphasen, insbesondere in den grenzschichtnahen Regionen verbunden und führen zu einem starken Anstieg der pro Zeiteinheit übertragenen Stoffmenge. Die Lösung der Diffusionsgleichung reicht in diesem Fall zur Vorausberechnung des für Auslegungszwecke bedeutsamen Stoffdurchgangskoeffizienten nicht mehr aus. Chemische Reaktionen stellen Quellen oder Senken von Wärme und Stoff dar, die das Auftreten von Instabilitäten begünstigen und die mathematische Beschreibung zusätzlich erschweren. Im Rahmen der vorliegenden Arbeit wurden experimentelle und numerische Untersuchungen zum Flüssig-Flüssig-Stoffübergang in einem vertikalen Kapillarspalt durchgeführt. Reaktionsfreie Stoffübergänge und solche mit einer exothermen chemischen Reaktion an der Phasengrenze zeigten eine große Vielfalt von Konvektionsstrukturen, wie Rollzellen, Thermiken und das doppeldiffusive Fingerregime. Die Visualisierung der Transportvorgänge erfolgte durch das Schattenschlierenverfahren. Die Beobachtungen wurden hinsichtlich geometrischer Eigenschaften von Konvektionsstrukturen sowie deren zeitlicher Änderung ausgewertet. Dazu zählten insbesondere das Längenwachstum von Thermiken und horizontale Wellenlängen von Fingerstrukturen. Zur mathematischen Beschreibung der Phänomene im Kapillarspalt wurde ein Modell entwickelt, welches auf den gekoppelten, zweidimensionalen Transportgleichungen von Impuls, Wärme und Stoff beruht. Es berücksichtigt dichte- und grenzflächenspannungsgetriebene Instabilitätsmechanismen sowie die besonderen Durchströmungseigenschaften des Kapillarspalts. Die Phasengrenze wurde als eben angenommen. Die Lösung der Modellgleichungen erfolgt auf numerischem Wege durch ein Computerprogramm. Das Modell ist in der Lage, die beobachteten Instabilitätsphänomene qualitativ richtig wiederzugeben. Mit Hilfe von Simulationsrechnungen konnte der Mechanismus aufgeklärt werden, der zum schnelleren Rückgang des Stoffdurchgangskoeffizienten im Rollzellenregime der rein grenzflächenspannungsgetrieben Instabilität im Vergleich zum Vorgang mit überlagerter Dichtekonvektion führt. Des Weiteren gelang der Nachweis des doppeldiffusiven Fingerregimes beim Stoffübergang mit exothermer Grenzflächenreaktion. Die berechnete Erhöhung des Stoffdurchgangskoeffizienten stimmt mit Angaben in experimentellen Arbeiten anderer Autoren überein.

Parabens are effective antibacterial and anti-fungal agents and are used extensively as preservatives in cosmetics, food and pharmaceutical products. Because of the presence of parabens in the environment and their negative effects on human health, there is an increasing interest in their trace analysis. Since the concentration of parabens in the environment are rather low and cosmetics present rather complex matrices for the analysis, it is necessary to apply a preconcentration or isolation step prior to the chromatographic analysis. The aim of this work was to develop liquid-phase microextraction methods – single drop microextraction, hollow fibre liquid phase microextraction and dispersive liquid-liquid microextraction – for parabens and to apply the methods for determination of parabens in water samples and cosmetic products. Extraction conditions for single drop microextraction, hollow fibre liquid phase microextraction and dispersive liquid-liquid microextraction were optimized and the quality parameters of the suggested methods were calculated. The influence of derivatization on the paraben extraction efficiency was evaluated. Prepared microextraction methods were applied for the determination of parabens in real samples. / Parabenai pasižymi antibakterinėmis bei priešgrybelinėmis savybėmis ir plačiai naudojami kosmetikos, maisto, farmacijos pramonėje kaip konservantai, apsaugantys produktus nuo ankstyvo gedimo ir prailginantys jų galiojimo laiką. Padidėjus įtarimams, jog prasiskverbę per odą parabenai gali sukelti alergines reakcijas, ardyti endokrininę sistemą, skatinti vėžinių ląstelių gamybą, buvo pradėta kontroliuoti jų kiekį aplinkoje, maisto bei kosmetikos produktuose. Tačiau parabenų koncentracijos dažnai yra per mažos, o mėginiai per daug sudėtingi, kad juos būtų galima analizuoti nesukoncentravus ir neizoliavus nuo trukdančios matricos. Šioje daktaro disertacijoje apibendrintų mokslinių tyrimų tikslas – sukurti parabenų skysčių-skysčių mikroekstrakcijos metodus – mikroekstrakciją tirpiklio lašu, skystafazę mikroekstrakciją kapiliare ir dispersinę skysčių-skysčių mikroekstrakciją – bei pritaikyti juos parabenų nustatymui vandenyje bei kosmetikos produktuose. Optimizuotos mikroekstrakcijos tirpiklio lašu, skystafazės mikroekstrakcijos kapiliare ir dispersinės skysčių-skysčių mikroekstrakcijos ekstrakcijos sąlygos ir nustatytos pagrindinės analizinės charakteristikos. Ištirta parabenų derivatizacijos įtaka parabenų dujų chromatografinio nustatymo efektyvumui. Paruošti parabenų mikroekstrakcijos metodai pritaikyti vandens ir kosmetikos mėginių analizei.

Parabenai pasižymi antibakterinėmis bei priešgrybelinėmis savybėmis ir plačiai naudojami kosmetikos, maisto, farmacijos pramonėje kaip konservantai, apsaugantys produktus nuo ankstyvo gedimo ir prailginantys jų galiojimo laiką. Padidėjus įtarimams, jog prasiskverbę per odą parabenai gali sukelti alergines reakcijas, ardyti endokrininę sistemą, skatinti vėžinių ląstelių gamybą, buvo pradėta kontroliuoti jų kiekį aplinkoje, maisto bei kosmetikos produktuose. Tačiau parabenų koncentracijos dažnai yra per mažos, o mėginiai per daug sudėtingi, kad juos būtų galima analizuoti nesukoncentravus ir neizoliavus nuo trukdančios matricos. Šioje daktaro disertacijoje apibendrintų mokslinių tyrimų tikslas – sukurti parabenų skysčių-skysčių mikroekstrakcijos metodus – mikroekstrakciją tirpiklio lašu, skystafazę mikroekstrakciją kapiliare ir dispersinę skysčių-skysčių mikroekstrakciją – bei pritaikyti juos parabenų nustatymui vandenyje bei kosmetikos produktuose. Optimizuotos mikroekstrakcijos tirpiklio lašu, skystafazės mikroekstrakcijos kapiliare ir dispersinės skysčių-skysčių mikroekstrakcijos ekstrakcijos sąlygos ir nustatytos pagrindinės analizinės charakteristikos. Ištirta parabenų derivatizacijos įtaka parabenų dujų chromatografinio nustatymo efektyvumui. Paruošti parabenų mikroekstrakcijos metodai pritaikyti vandens ir kosmetikos mėginių analizei. / Parabens are effective antibacterial and anti-fungal agents and are used extensively as preservatives in cosmetics, food and pharmaceutical products. Because of the presence of parabens in the environment and their negative effects on human health, there is an increasing interest in their trace analysis. Since the concentration of parabens in the environment are rather low and cosmetics present rather complex matrices for the analysis, it is necessary to apply a preconcentration or isolation step prior to the chromatographic analysis. The aim of this work was to develop liquid-phase microextraction methods – single drop microextraction, hollow fibre liquid phase microextraction and dispersive liquid-liquid microextraction – for parabens and to apply the methods for determination of parabens in water samples and cosmetic products. Extraction conditions for single drop microextraction, hollow fibre liquid phase microextraction and dispersive liquid-liquid microextraction were optimized and the quality parameters of the suggested methods were calculated. The influence of derivatization on the paraben extraction efficiency was evaluated. Prepared microextraction methods were applied for the determination of parabens in real samples.

Water is a crucial natural resource, indispensable to food production, life, the environment, power generation, industry, sanitation and hygiene. The presence of Organochlorine Pesticides (OCPs) in the environment is not wanted due to their negative effects on human beings and animals. As a result, there is a need to continuously monitor their presence in the environment. In this study, surface water samples were collected once a month during the dry season and during wet season from the selected five points along the Olifants River and stored at a temperature of < 50C before analysis. The OCPs were extracted with dichloromethane (DCM) using the Liquid-Liquid Extraction (LLE) method. After undertaking the sample through the clean- up process, the crude extracts obtained were put into the column chromatography and eluted with hexane, about 1.5 μL of the purified extracts were analysed by the Gas Chromatographic- Mass Spectrophotometer (GC/MS). The percentage recoveries, varied from 32- 116 % for p, p’-DDT and 4,4'-DDD respectively in triply spiked water samples. The standard deviation for most of the compounds is less than±0.04, with the exclusion of Heptachlor (±0.14). The seasonal variability of OCPs in water samples along Olifants River results show that in dry season, the Olifants River is mostly polluted at the Oxford site with (BHC-beta, Aldrin, Heptachlor-epoxide, Endosulfan-alpha and Endrin), at the Ga- Selati site with (Heptachlor-epoxide and Endrin) and at the Wolvekrans site with (Endosulfan-alpha), with Aldrin up to 834.20 ng/ L indicating the highest hazard toward the aquatic environment while in summer the Olifants River is mostly polluted at the Ga- selati site with BHC-beta and at the Waterval site with (Heptachlor and BHC-gamma) with BHC- gamma up to 560 ng/ L indicating the highest hazard toward the aquatic environment. The levels reached from the Olifants River catchment were meaningfully above the drinking water quality guidelines for organic chemical recommended by WHO, 2006 i.e. (BHC-gamma,DDT-44, Aldrin, dieldrin and Endrin are (2.0,1.0,0.03,0.03 and 0.6) respectively for the protection of the domestic use, aquatic ecology and agricultural use (irrigation and livestock watering) for compounds with local guideline values; while, the international water quality guidelines to protect the aquatic ecosystems are 0.00083 ng/mℓ (4,4’DDD), 0.00059 ng/mL (4,4’DDE), (4,4’DDT), 0.00021 ng/mL (heptachlor), 0.0092 ng/mℓ (α-HCH), 0.0186 ng/mL (γ- HCH), and chronic values are 0.056 ng/mL (ENDO I and II) and 0.0023 ng/mL endrin) (USEPA, 2002). Levels detected were significantly higher than some research studies conducted up to now in South African aquatic environments. These results confirm the contamination of the Olifants River catchment by the OCPs. / Water and Sanitation / M. Sc. (Environmental Science)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this study, an analytical method was developed for the quantification of statins Atorvastatin and Simvastatin, in hospital effluent (University Hospital of Santa Maria, using Solid phase extraction and Dispersive liquid-liquid microextraction, followed in liquid chromatography coupled to diode array detector. The principal variables of Dispersive liquid-liquid microextraction were investigated with aid of experimental central composite design. The recovery rates of Solid phase extraction varied from 95% for Atorvastatin and 83.2% for Simvastatin, in aqueous solution, and 92.0% for Atorvastatin and 81.5% for Simvastatin, in hospital effluent. As for the Dispersive liquid-liquid microextraction the recovery rates ranged from 85.5% for Atorvastatin and 89.4% for Simvastatin, in aqueous solution, and 83.0% for Atorvastatin and 83.1% for Simvastatin, in hospital effluent. The sampling was carried out in two sample points called Emergency Effluent and General Effluent . The concentration rates detected in the effluent were 30.1 μg L-1 in Emergency Effluent and 29.0 μg L-1 in General Effluent for Atorvastatin and 37.1 μg L-1 in Emergency Effluent and 36.1 μg L-1 in GE for Simvastatin. Ozonation and electrocoagulation were applied for the degradation/removal of statins. The principal variables of electrocoagulation were investigated with aid of experimental central composite design. The degradation rate obtained in ozonation was 100% for Atorvastatin, in 25 minutes reaction for aqueous solution and hospital effluent; and 100% for Simvastatin, in 4 minutes reaction for aqueous solution and 10 minutes reaction in hospital effluent. As for the electrocoagulation the removal rate was 75.6% in aqueous solution and 70.9% in hospital effluent for Atorvastatin; and 100% in aqueous solution and hospital effluent for Simvastatin in 60 minutes reaction. A preliminary risk evaluation revealed that the statins showed a low environmental risk, PEC/PNEC < 1. / Neste trabalho foi desenvolvida metodologia analítica para a quantificação de estatinas Atorvastatina e Sinvastatina, em efluente hospitalar (Hospital Universitário de Santa Maria), utilizando Extração em fase sólida e Microextração dispersiva líquido-líquido seguida de cromatografia líquida com detector de arranjo de diodos. As principais variáveis da Microextração dispersiva líquido-líquido foram investigadas utilizando a Metodologia de Superfície de Resposta através de um delineamento composto central rotacional. As taxas de recuperação da Extração em fase sólida foram de 95,8% para Atorvastatina e 83,5% para Sinvastatina, em solução aquosa e 92,0% para Atorvastatina e 81,5% para Sinvastatina em efluente hospitalar. Já para a Microextração dispersiva líquido-líquido as taxas de recuperação foram de 85,5% para Atorvastatina e 89,4% para Sinvastatina, em solução aquosa e 83,0% para Atorvastatina e 83,1% para Sinvastatina, em efluente hospitalar. A amostragem foi feita em dois pontos de coleta, denominados Efluente PA e Efluente Geral . A concentração média detectada no efluente foi de 30,1 μg L-1 no Efluente PA e 29,0 μg L-1 no Efluente Geral para Atorvastatina e 37,1 μg L-1 no Efluente PA e 36,1 μg L-1 no Efluente Geral para Sinvastatina. Ozonização e eletrocoagulação foram aplicados na degradação/remoção das estatinas. As principais variáveis da eletrocoagulação foram investigadas utilizando a Metodologia de Superfície de Resposta através de um delineamento composto central. As taxas de degradação obtidas na ozonização foram de 100% para Atorvastatina, em 25 min de reação, para solução aquosa e efluente hospitalar; e 100% para Sinvastatina em 4 min em solução aquosa, e 10 min em efluente hospitalar. Já para a eletrocoagulação as taxas de remoção foram de 75,9% em solução aquosa e 70,9% em efluente hospitalar para Atorvastatina; e 100% para solução aquosa e afluente hospitalar para Sinvastatina, em 60 min de reação. A análise preliminar de risco ambiental revelou que as estatinas apresentam baixo risco ambiental, com PEC/PNEC < 1.

Made available in DSpace on 2014-12-17T14:08:46Z (GMT). No. of bitstreams: 1 ZildianyIM_DISSERT.pdf: 2328964 bytes, checksum: cce13a45c02b28ab140a7f90a8548746 (MD5) Previous issue date: 2011-07-04 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Boron is a semi-metal present in certain types of soils and natural waters. It is essential to the healthy development of plants and non-toxic to humans, depending on its concentration. It is used in various industries and it s present in water production coming from oil production. More specifically in Rio Grande do Norte, one of the largest oil producers on shore of Brazil, the relationship water/oil in some fields becomes more than 90%. The most common destination of this produced water is disposal in open sea after processing to meet the legal specification. In this context, this research proposes to study the extraction of boron in water produced by microemulsion systems for industrial utilization. It was taken into account the efficiency of extraction of boron related to surfactant (DDA and OCS, both characterized by FT-IR), cosurfactant (butanol and isoamyl alcohol), organic phase (kerosene and heptanes) and aqueous phase (solution of boron 3.6 ppm in alkaline pH). The ratio cosurfactant/ surfactant used was four and the percentage of organic phases for all points of study was set at 5%. It was chosen points with the highest percentage of aqueous phase. Each system was designed for three points of different compositions in relation to the constituents of a pseudoternary diagram. These points were chosen according to studies of phase behavior in pseudoternary diagrams made in previous studies. For this research, points were chosen in the Winsor II region. The excess aqueous solution obtained in these systems was separated and analyzed by ICP OES. For the data set obtained, the better efficiency in the extraction of boron was obtained using the system with DAC, isoamyl alcohol and heptanes, which extracted 49% in a single step. OCS was not viable to the extraction of boron by microemulsion system in the conditions defined in this study / O boro ? um semi-metal presente em determinados tipos de solos e ?guas naturais. ? essencial ao desenvolvimento sadio de esp?cies vegetais e at?xico ao homem, dependendo de sua concentra??o. ? utilizado em v?rias ind?strias e est? presente em ?guas de produ??o oriundas da atividade petrol?fera. Mais especificamente no Rio Grande do Norte, um dos maiores produtores de petr?leo on shore do Brasil, a mistura ?gua/?leo produzida em alguns campos chega a ser superior a 90% em ?gua. O destino mais comum a essa ?gua produzida ? o descarte no mar aberto ap?s especifica??o. Com isso, o objeto a que se prop?e este trabalho ? o estudo da extra??o do boro em ?gua produzida por sistema microemulsionado (SME) para seu aproveitamento industrial. Nesse estudo foi levado em considera??o a efici?ncia de extra??o de boro quanto ao tensoativo (DDA e OCS, ambos caracterizados por FT-IV), cotensoativo (butanol e ?lcool isoam?lico), fase org?nica (querosene e heptano) e fase aquosa (solu??o de boro 3,6 ppm em pH b?sico). A raz?o cotensoativo/tensoativo utilizada foi quatro e o percentual das fases org?nicas para todos os pontos de estudo foi fixada em 5%. Foram escolhidos pontos com maior percentual de fase aquosa. Cada sistema foi montado para tr?s pontos de composi??es diferentes em rela??o aos constituintes de um diagrama pseudotern?rio. Estes pontos foram escolhidos de acordo com estudos do comportamento de fases em diagramas pseudotern?rios realizados em estudos anteriores. Para esse estudo os pontos escolhidos localizaram-se na regi?o de Winsor II. A solu??o aquosa em excesso obtida nesses sistemas foi separada e analisada por ICP OES. Do conjunto de dados obtidos, o sistema que apresentou melhor efici?ncia na extra??o de boro foi o que utilizou DAC, ?lcool isoam?lico e heptano, com aproximadamente 49% de extra??o numa ?nica etapa. O OCS n?o se mostrou favor?vel a extra??es de boro por sistema microemulsionados nas condi??es do estudo

Made available in DSpace on 2014-12-17T15:01:20Z (GMT). No. of bitstreams: 1 WilaciEFJ.pdf: 1838358 bytes, checksum: 40ec11f34b65cc0544a9b15c91dae65a (MD5) Previous issue date: 2002-04-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The present work had as objective to apply an experimental planning aiming at to improve the efficiency of separation of a new type of mixer-settler applied to treat waste water contaminated with oil. An unity in scale of laboratory, was installed in the Post-graduation Program of Chemical Engineering of UFRN. It was constructed in partnership with Petrobras S.A. This called device Misturador-Decantador a Invers?o de Fases (MDIF) , possess features of conventional mixer-settler and spray column type. The equipment is composed of three main parts: mixing chamber; chamber of decantation and chamber of separation. The efficiency of separation is evaluated analyzing the oil concentrations in water in the feed and the output of the device. For the analysis one used the gravimetric method of oil and greases analysis (TOG). The system in study is a water of formation emulsified with oil. The used extractant is a mixture of Turpentine spirit hydro-carbons, supplied for Petrobras. It was applied, for otimization of the efficiency of separation of the equipment, an experimental planning of the composite central type, having as factorial portion fractionary factorial planning 2 5-2, with the magnifying of the type star and five replications in the central point. In this work, the following independents variables were studied: contents of oil in the feed of the device; volumetric ratio (O/A); total flowrate ; agitation in the mixing chamber and height of the organic bed. Minimum and maximum limits for the studied variables had been fixed according previous works. The analysis of variance for the equation of the empirical model, revealed statistically significant and useful results for predictions ends. The variance analysis also presented the distribution of the error as a normal distribution and was observed that as the dispersions do not depend on the levels of the factors, the independence assumption can be verified. The variation around the average is explained by 98.98%, or either, equal to the maximum value, being the smoothing of the model in relation to the experimental points of 0,98981. The results present a strong interaction between the variable oil contents in the feed and agitation in the mixing chamber, having great and positive influence in the separation efficiency. Another variable that presented a great positive influence was the height of the organic bed. The best results of separation efficiency had been obtained for high flowrates when associates the high oil concentrations and high agitation. The results of the present work had shown excellent agreement with the results carried out through previous works with the mixer-settler of phase inversion / O presente trabalho teve como objetivo otimizar a efici?ncia de separa??o de um novo aparelho do tipo misturador-decantador aplicado ao tratamento de ?guas residu?rias contaminadas com petr?leo. Foi utilizado um equipamento em escala de laborat?rio, instalado no Programa de P?s-gradua??o em Engenharia Qu?mica da UFRN, que foi constru?do em parceria com a Petrobras S.A. Este aparelho denominado Misturador-Decantador ? Invers?o de Fases (MDIF), possui caracter?sticas de um misturador-decantador convencional e de uma coluna tipo spray. O equipamento ? composto de tr?s partes principais: c?mara de mistura; c?mara de decanta??o e c?mara de separa??o. A efici?ncia de separa??o ? avaliada analisando-se as concentra??es de ?leo em ?gua na alimenta??o e na sa?da do aparelho. Para a an?lise utilizou-se o m?todo da an?lise de ?leo e graxas (TOG) por gravimetria. O sistema em estudo ? uma ?gua de forma??o emulsionada com ?leo. O extratante utilizado ? uma mistura de hidrocarbonetos denominada de Aguarr?s, fornecido pela Petrobras. Aplicou-se, para a otimiza??o da efici?ncia de separa??o do equipamento, um planejamento experimental do tipo central composto, tendo como por??o fatorial o planejamento fatorial fracion?rio 2 5-2, com a amplia??o do tipo estrela e cinco repeti??es no ponto central. Neste trabalho, estudam-se as seguintes vari?veis independentes: teor de ?leo na ?gua residu?ria de carga da coluna; rela??o volum?trica org?nico/aquoso (O/A); vaz?o efetiva total; agita??o na c?mara de mistura e altura do leito org?nico. Foram fixados limites m?nimos e m?ximos para as vari?veis estudadas de acordo com trabalhos realizados anteriormente. A an?lise de vari?ncia para a equa??o do modelo emp?rico, mostrou-se estatisticamente significante e ?til para fins preditivos. A an?lise de vari?ncia tamb?m apresentou a distribui??o do erro como uma distribui??o normal e observou-se que como as dispers?es n?o dependem dos n?veis dos fatores, a suposi??o de independ?ncia pode ser verificada. A varia??o em torno da m?dia ? explicada por 98,98%, ou seja, igual ao valor m?ximo explic?vel, sendo o ajuste do modelo em rela??o aos pontos experimentais de 0.98981. Os resultados apresentam uma intera??o muito forte entre as vari?veis teor de ?leo e agita??o na c?mara de mistura, tendo grande e positiva influ?ncia na efici?ncia de separa??o. Outra vari?vel que apresentou-se com grande e positiva influ?ncia foi a altura do leito org?nico. Os melhores resultados de efici?ncia de separa??o foram obtidos para altas vaz?es quando associadas a altas concentra??es de ?leo e alta agita??o. Os resultados obtidos no presente trabalho mostraram excelente concord?ncia com os resultados de trabalhos anteriores realizados com o misturador-decantador ? invers?o de fases