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Studies of phase separable soluble polymersFuryk, Steven Michael 16 August 2006 (has links)
The technique of phase labeling has the ability to greatly enhance synthetic
protocol by simplifying purification and increasing efficiency. Traditional insoluble
supports offer efficient and simple recovery of the Âphase tagged material but suffer
from problems inherent to their heterogeneous nature. A solution to these problems has
been to utilize phase separable soluble polymers in the design of Âsmart responsive
systems that offer the option of homogenous reaction conditions with heterogeneous
separation conditions. The subject of this dissertation focuses on the application of
soluble polymeric phase tags in systems where the miscibility between solid-liquid and
liquid-liquid systems is thermally induced.
Low molecular weight poly(ethylene glycol) (PEG) oligomers were investigated
as phase anchors for SCS palladacycle catalysts. The oligomeric PEG chains were
sufficient to engender polar phase solubility in a heptane-DMA thermomorphic system.
Microwave irradiation of these thermomorphic mixtures of palladium complexes and
substrates was a viable scheme to recycle and significantly shorten reaction times for
simple Heck reactions of aryl iodides. Soluble polymeric supports possessing a lower critical solution temperature
(LCST) were utilized in the sequestration of the S-triazine herbicide, atrazine, from
contaminated water samples. The ability of poly(N-isopropylacrylamide) to sequester
hydrophobic guests like atrazine was examined. A functionalized PNIPAM derivative
containing secondary cyclic amines exhibited superior sequestration ability that was
credited to the covalent binding of the atrazine.
In order to facilitate the design of tailored, thermally responsive, smart polymers,
a high throughput temperature gradient microfluidic device was used to obtain LCST
data in a fast, accurate manner. The specific ion effects of various alkali metal halide
salts on the LCST of PNIPAM were investigated. The high precision in the
measurements enabled more subtle effects such as changes in solvent isotope, polymer
microstructure, molecular weight, and importance of end group effects on the LCST of
poly(N-alkylacrylamide)s to be evaluated.
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Estudo da estabilidade de triazinana sob condi??es de processamento para o sequestro de H2S / Study of triazinane stability under processing conditions for H2S sequestrationSILVA, Matheus Gomes 27 July 2016 (has links)
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Previous issue date: 2016-07-27 / The Hidrogen sulfide is one of the substances most dangers in the oil and gas production. The H2S causes great economic losses to industries and so their removal is desired. The use of the triazine to remove the H2S has been extensively documented in the literature. However, the number of products that present the physical and chemical properties desired to act as H2S scavenger, available in the market, is reduced. For this reason, the search by molecules that act in removing of H2S has been the object of research in the worldwide. The goal of this work was investigate the thermal stability of two different H2S scavengers: 1,3,5-tris (hydroxyethyl) hexahydro-s-triazine (commercial) and 1,3,5-tris (hydroxypropyl) hexahydro-s-triazine (synthesized in our laboratory ) when they are subject to processing condition in a pilot plant. To achieve this goal was built a pilot plant capable of simulating some operating conditions of the pre-salt exploration, such as temperature, shear rate and residence time. The thermal stability (degradation) of the triazines was investigated by monitoring the conductivity of the samples. For comparison purposes were performed condutimetry tests of samples in bench tests in the laboratory and pilot plant at temperatures of 30?C, 40?C, 50?C, 60?C and 80?C. For both triazines, the conductivity values obtained in the pilot plant is much higher than those found in bench tests: 65.1 S/cm (2C) and 65.1 S/cm (3C) and 45.5 S/cm (2C), and 32.1 S/cm (3C) respectively. The results showed that the conductivity values are strongly affected by the processing time, being more evident differences in their bench tests. The results of monitoring the conductivity of the samples allowed to verify that the 1,3,5-tris (hydroxyethyl) hexahydro-s-triazine (commercial) and 1,3,5-tris (hydroxypropyl) hexahydro-s- triazine (synthesized in our laboratory) does not undergo degradation under the process conditions which have been subjected, either in bench tests or plant pilot. / O sulfeto de Hidrog?nio ? uma das subst?ncias mais perigosas na produ??o de petr?leo e g?s. O H2S provoca grandes perdas econ?micas para as ind?strias e assim a sua remo??o ? desejada. O uso da triazina para remover o H2S tem sido extensivamente documentado na literatura. No entanto, o n?mero de produtos que apresentam propriedades f?sicas e qu?micas desejadas para actuar como eliminador de H2S, dispon?vel no mercado, ? reduzida. Por esta raz?o, a busca por mol?culas que atuem na remo??o de H2S tem sido o objeto de pesquisa no mundo inteiro. O objectivo deste trabalho foi o de investigar a estabilidade t?rmica de duas diferentes sequestrantes de H2S: 1,3,5-tris (hidroxietil) hexa-hidro-s-triazina (comercial) e 1,3,5-tris (hidroxipropil) hexa-hidro-s-triazina (sintetizada em laborat?rio), quando eles est?o sujeitos a condi??o de processamento em uma planta piloto. Para atingir este objetivo foi constru?da uma planta piloto capaz de simular algumas condi??es de processamento da explora??o do pr?-sal, tais como temperatura, taxa de cisalhamento e tempo de resid?ncia. A estabilidade t?rmica (degrada??o) das triazinas, foi investigada atrav?s da monitoriza??o da condutividade das amostras. Para fins de compara??o foram realizados testes condutimetria de amostras em ensaios de bancada de laborat?rio e na planta piloto nas temperaturas de 30?C, 40?C, 50?C, 60?C e 80?C. Para ambas as triazinas, os valores de condutividade obtidos na instala??o piloto ? muito mais elevado do que aqueles encontrados no banco: 65,1 S/cm (2c) e 65,1 S/cm (3C) e 45,5 S/cm (2C), e 32,1 S/cm (3C), respectivamente. Os resultados mostraram que os valores de condutividade s?o fortemente afetados pelo tempo de processamento, sendo as diferen?as mais evidentes em seus testes de bancada. Os resultados da monitoriza??o da condutividade das amostras permitiram verificar que o 1,3,5-tris (hidroxietil) hexa-hidro-s-triazina (comercial) e 1,3,5-tris (hidroxipropil) hexa-hidro-triazina S- (sintetizado no nosso laborat?rio) n?o sofre degrada??o sob as condi??es de processo que foram sujeitos, tanto em testes de bancada ou planta piloto
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