Ion exchange chromatography (IC) is an analytical technique used to separate charged molecules including ions, proteins, small nucleotides, and amino acids. It can function in anion or cation mode. In this dissertation, anion exchange chromatography was used, and column materials were made in our lab with resorcinarene-based compounds called cavitands. Cavitands create cavities to bind to molecules because of their three-dimensional structure. Two new gradient IC methods were established to identify and quantify perrhenate and perfluoroalkyl substances (PFAS) by customized resorcinarene-based column, zinc cyclen resoecinarene (ZCR) and arginine methyl ester (RUE) columns. The ZCR column accomplished outstanding separation of perrhenate from other anions such as chloride and sulfate by using a gradient elution of 2-60 mM NaOH. There was a logarithmic relationship between the perrhenate concentration and its retention time. In addition to separating anions, the ZCR column was able to preconcentrate perrhenate with over 90% recovery in different conditions. RUE was successfully synthesized and attached to polystyrene resin and used in IC to separate the PFAS, perfluorobutanoic acid (PFBA), perfluoropentanoic acid (PFPeA), perfluorobutanesulfonic acid (PFBS), perfluorohexanoic acid (PFHxA), perfluorohexanesulphonic acid (PFHxS), and perfluorooctanoic acid (PFOA). The sample preparation for the PFAS was simple and only needed filtration. A gradient method starting with 70 mM NaOH and going to pure water was necessary to separate the PFAS. There was no detectable PFAS in Provo tap water and Utah Lake water by our method. Although the LOD and LOQ of PFAS were not as low as the existing methods, the IC method does not require complicated sample preparation steps to separate and quantify PFAS. Binding studies of RUE and RUA were done with organic acids, including citric, malic, and succinic acid, and PFAS including PFBA, and PFHxA. The strongest binding was for L-malic acid followed by succinic acid, D-malic acid, pentanoic acid, citric acid, and dimethyl L-malate. RUE displayed some chiral recognition between L-malic acid and D-malic acid. Unfortunately, it did not show significant differences in binding between the different PFAS even though RUE had been able to separate them by IC.

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BACKGROUND:The widespread utilization of organic compounds in modern society and their dispersion through wastewater have resulted in extensive contamination of source and drinking waters. The vast majority of these compounds are not regulated in wastewater outfalls or in drinking water while trace amounts of certain compounds can impact aquatic wildlife. Hence it is prudent to monitor these contaminants in water sources until sufficient toxicological data relevant to humans becomes available. A method was developed for the analysis of 36 trace organic contaminants (TOrCs) including pharmaceuticals, pesticides, steroid hormones (androgens, progestins, and glucocorticoids), personal care products and polyfluorinated compounds (PFCs) using a single solid phase extraction (SPE) technique with ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The method was applied to a variety of water matrices to demonstrate method performance and reliability.RESULTS:UHPLC-MS/MS in both positive and negative electrospray ionization (ESI) modes was employed to achieve optimum sensitivity while reducing sample analysis time (<20min) compared with previously published methods. The detection limits for most compounds was lower than 1.0 picogram on the column while reporting limits in water ranged from 0.1 to 15ng/L based on the extraction of a 1L sample and concentration to 1mL. Recoveries in ultrapure water for most compounds were between 90-110%, while recoveries in surface water and wastewater were in the range of 39-121% and 38-141% respectively. The analytical method was successfully applied to analyze samples across several different water matrices including wastewater, groundwater, surface water and drinking water at different stages of the treatment. Among several compounds detected in wastewater, sucralose and TCPP showed the highest concentrations.CONCLUSION:The proposed method is sensitive, rapid and robust / hence it can be used to analyze a large variety of trace organic compounds in different water matrixes.

Atualmente, os consumidores valorizam produtos com garantia de qualidade e que sejam obtidos de cadeias ecologicamente corretas e socialmente justas. A rastreabilidade da cadeia produtiva possui importância fundamental para o aumento do consumo de pescado. Um dos principais gargalos da cadeia produtiva é o reduzido aproveitamento do resíduo do processamento. A elaboração de silagem de pescado é uma alternativa para minimizar os problemas ambientais e de sanidade, provenientes do resíduo de pescado, porém esta deve ser preparada com agentes acidificantes sustentáveis e que sejam selecionados através de análise de mercado levando em consideração os riscos ambientais e para a saúde humana, o custo e a facilidade de compra do agente acidificante, um dos objetivos dessa pesquisa. A utilização do ácido cítrico aparentou ser a melhor escolha. Avaliou-se o desempenho de 180 alevinos de sargo (Diplodus sargus) (21,30 ± 0,87 g) alimentados com 6 dietas isoenergéticas (3.941 kcal/kg), contendo dois níveis de proteína bruta PB (35 e 45%) e três níveis de inclusão (0, 10 e 20%) de silagem de resíduos provenientes da indústria conserveira da cidade do Porto, Portugal. Não houve mortalidade e as dietas experimentais foram bem aceitas. Não houve diferença (P<0,05) no consumo das rações, fator de condição, índice hepatossomático, índice de conversão alimentar e ganho de peso. É possível a inclusão de até 20% de silagem em dietas para o sargo e sugere-se a utilização das rações formuladas contendo 45% de PB por apresentarem menor custo de produção e empregarem maior quantidade de material residual proveniente do processamento de pescado. Em Portugal, o setor pesqueiro ocupa espaço destacado entre as atividades econômicas. A relevância desta cadeia produtiva resulta, essencialmente, do fato de que o pescado é componente fundamental da alimentação e responsável por elevado número de empregos da população. No Brasil, com o aumento do número de indústrias beneficiadoras, o resíduo desta atividade tornou-se um sério problema. Buscou-se classificar o resíduo do beneficiamento da tilápia do Nilo (Oreochromis niloticus), conforme a Associação Brasileira de Normas Técnicas (ABNT NBR 10004:2004), foram coletadas vinte e quatro amostras; três em cada período (ago/07, set/2007, out/2007, dez/2007, fev/2008, mai/2008, jul/2008, ago/2008). Todas as amostras foram classificadas como Classe II, do tipo Não Inerte devido aos teores de chumbo, manganês, surfactantes e ferro. Esses resíduos devem ser destinados a aterros sanitários construídos conforme normas específicas. Entretanto, estão sendo descartados de forma irregular, diretamente em recursos hídricos ou enterrados sem tratamento com riscos ao ambiente e à saúde humana e animal pela possibilidade de lixiviação de metais / Currently, consumers value products with assurance of quality and obtained from environmentally friendly and socially just chain. The traceability of the commodity chain has fundamental importance to increase the fish consumption. One of the main bottlenecks in the commodity chain is the reduced utilization of processing residue. The elaboration of fish silage is an alternative to minimize the environmental and sanity problems from fish residue. In order to select the most appropriate acid for the preparation of chemical fish silage, market analysis considering environmental and human risks, cost and supply of acidifying agent was performed. The use of citric acid seems to be the best choice. The performance of 180 bream fingerlings (21.30 ± 0.87 g) fed six isoenergetic diets (3,941 kcal/kg) containing two levels of crude protein - CP (35 and 45%) and three levels of inclusion of silage (0, 10 and 20%) was evaluated. There was no mortality and the experimental diets were well accepted. There was no difference (P<0.05) in diets intake, condition factor, hepatosomatic index, food conversion ratio and weight gain. Weight gain and food conversion ratio were 9.61 g and 2.77, 9.23 g and 2.99, 9.95 g and 3.04, 11.81 g and 2.86, 13.41 g and 2.14, and 11.36 g and 2.41 for treatments 1 (35% CP; 0% inclusion), 2 (35% CP, 10% inclusion), 3 (35% CP, 20% inclusion), 4 (45% CP; 0% inclusion), 5 (45% CP, 10% inclusion) and 6 (45% CP, 20% inclusion), respectively. Therefore, it is possible to include up to 20% of fish silage in diets for bream and suggests the use of diets containing 45% CP because of their lower cost of production and for using higher amount of residual material from fish processing. The fisheries sector occupies an important position in the economic activities in Portugal. Its relevance is due to fish being a fundamental component of food and responsible for employment opportunities. In Brazil, the increasing number of fish processing industries, the residue of this activity has become a serious problem. The residue from the processing of Nile tilapia (Oreochromis niloticus) was classified according to the Brazilian Association of Technical Standards (ABNT NBR 10004:2004). A total of twenty-four samples were collected, three in each period (Aug/07, Sep/2007, Oct/2007, Dec/2007, Feb/2008, May/2008, Jul/2008, Aug/2008). All analyzed samples were classified as Class II, Non Inert, due to the lead, manganese, iron and surfactants levels. These wastes should be disposed of in landfills constructed according to environmental standards. However, they are being improperly disposed, dumped directly into water or buried without proper treatment, providing risk to the environment and human and animal health due to possible leaching of metals

É crescente a demanda por materiais que atendam as exigências para construção de barreiras selantes (liners) em obras para disposição de resíduos. A utilização de solos tropicais para esta finalidade só não é maior por falta de conhecimento sobre muitas de suas características técnicas, principalmente a migração de contaminantes. Tentativas de melhoria das qualidades de solos supostamente inadequados também são importantes. Esta tese apresenta estudos sobre a migração dos íons \'CD POT.2+\', \'K POT.+\', \'CL POT.1-\' e \'F POT.-\' em latossolos residuais das formações Botucatu e Serra Geral e três diferentes misturas destes solos, com ênfase nos processos de sorção e difusão molecular. O potencial de retenção dos íons é avaliado através da construção de 33 isotermas de sorção resultantes de ensaios de equilíbrio em lote. Seus parâmetros são obtidos da adequação dos modelos linear, Freundlich e Langmuir as isotermas. O potencial de transporte dos íons é avaliado através de ensaios de difusão em colunas estanques, onde curvas teóricas produzidas no programa POLLUTE são ajustadas aos dados de concentração para a estimativa dos parâmetros de difusão. Os resultados dos estudos de retenção mostram que o \'CL POT.-\' experimenta sorção sob certas condições, o \'K POT.+\' e \'F POT.-\' possuem taxas semelhantes de retenção, e que a sorção do \'CD POT.2+\' se mostrou altamente dependente da composição da solução contaminante. Os ensaios de difusão resultaram em vários valores para o coeficiente de difusão efetiva (D*), mostrando que o fluxo difusivo dos íons diminui para solos mais argilosos. / There is a growing demand for materials that can be used in lining systems for waste disposal facilities. The use of tropical soils for this purpose is restricted due to the lack of technical knowledge about this type of material. Attempts to improve the quality of supposed unsuitable soils play also an important role. This thesis presents studies concerning the migration of the ions \'CD POT.2+\', \'K POT.+\', \'CL POT.-\' and \'F POT.-\' in latosoils from the Botucatu and Serra Geral formations and three different mixtures of these soils, with emphasis on sorption and molecular diffusion. Batch equilibrium tests were conduced to examine the retention capacity of the soils, and the sorption parameters are estimated by fitting the linear, Freundlich and Langmuir models to the experimental isotherm plots. The potential for these soils to transport ions is evaluated by diffusion tests, where theoretical curves produced in the POLLUTE code are used to estimate the effective diffusion coefficients (D*). The results show that the \'CL POT.-\' is sorbed under specific conditions and, therefore, it can not always be used as a conservative ion (i.e. nonreactive ion), \'K POT.+\' and \'F POT.-\' are sorbed in similar amounts, and that the \'CD POT.2+\' sorption is highly dependent on the contaminant solution composition. Several D* values are reported, showing that the diffusion rates are decreased for soils with more clay.

Este trabalho trata de um estudo experimental das respostas de desgaste e de atrito encontradas em um sistema deslizante lubrificado. Para tanto, foram realizados ensaios de deslizamento em um equipamento para ensaios de desgaste, adotando-se o dispositivo pino-contra-disco, para ensaios com movimento relativo rotativo contínuo entre as amostras, e o dispositivo pino-contra-placa, para ensaios com movimento relativo alternado, ou oscilatório, entre as amostras. Os materiais metálicos ensaiados foram pinos de aço AISI 52100 e contra-corpos de aço AISI 8640. O óleo lubrificante foi o mineral de base parafínico, IV 100. Foram variadas as condições de aditivação e de contaminação do óleo lubrificante e foram utilizados dois níveis de carregamento mecânico, determinada pela relação velocidade/carga. O desgaste foi estudado por microscopia óptica e eletrônica de varredura, medição da área afetada pelo desgaste, perfilometria das superfícies desgastadas e análise de óleo. O atrito e o potencial de contato foram monitorados ao longo dos ensaios. Os resultados obtidos mostraram que o desgaste dos corpos metálicos foi sensível ao carregamento mecânico, à aditivação e à contaminação do óleo. Diferenças foram notadas nas morfologias superficiais entre os resultados de desgaste dos ensaios rotativos e oscilatórios. / This work concerns with experimental study of wear and friction responses of lubricated sliding system. Sliding tests were carried out using pin-on-disk wear testing machine for tests with continuous rotating movement, and the pin-on-plate device, for reciprocating tests between specimens. The metallic test coupons were AISI 52100 steel pins and AISI 8640 steel counter-faces. The used lubricant was paraffinic mineral oil, VI 100. The presence of additives and contamination in the lubricant oil were investigated under two mechanical loading levels, determined by the velocity/load relation. The wear was studied by means of optic and scanning electronic microscopes, perfilometry and dimensional analysis of the worn surfaces and oil analysis. The friction and the contact potential were monitored through out the sliding tests. The results showed that the wear of the metallic materials was susceptible to the mechanical loading, the additive and the contamination existence in the oil. It was observed differences among the wear results of the rotating and the reciprocating tests in terms of surface morphologies.

No presente trabalho, métodos analíticos empregando a eletroforese capilar com detecção condutométrica sem contato CE - C4D foram desenvolvidos para a determinação de diversas espécies no biodiesel e etanol combustível. A concentração das espécies inorgânicas (Na+, K+, Ca2+, Mg2+, SO4 2- e PO4 3-) e glicerol no biodiesel são de interesse das agências reguladoras devido à capacidade dessas espécies em formar compostos indesejáveis no motor. A separação dos cátions foi realizada utilizando eletrólito de corrida (BGE) contendo 30 mmol L-1 de Ácido 2-N-morfolino-etanosulfônico (MES) / L-histidina, pH 6. A separação das espécies aniônicas foi realizada em BGE semelhante contendo 0,2 mmol L-1 brometo de cetiltrimetilamônio. Para a determinação do glicerol, que é uma espécie neutra, foi empregada uma etapa de oxidação utilizando periodato. Esta reação é específica para polióis e tem como um dos produtos o iodato. A quantidade de iodato produzida pela reação foi determinada por CE. A separação foi realizada em aproximadamente 1 min, utilizando BGE contendo 30 mmol L-1 de ácido acético, pH 3. Este trabalho também apresenta estudos sobre a formação de ácidos orgânicos de baixo PM durante a etapa de auto-oxidação do biodiesel, uma vez que esta etapa acarreta no aumento da viscosidade e acidez, ocasionando a formação de gomas e sedimentos e, conseqüentemente, o entupimento de filtros de combustíveis. As amostras foram oxidadas utilizando equipamento para teste de oxidação acelerada (Método Rancimat) e CE - C4D foi utilizada para a análise dos produtos iônicos formados. As principais espécies ácidas encontradas foram os ácidos acético e fórmico. Porém, outras espécies são formadas durante esta etapa, tais como os ácidos acrílico, glicólico, glioxílico, láctico e propiônico. Em particular, o ácido glicólico se mostrou uma espécie de grande importância prática, atuando como um marcador do estágio de oxidação do biodiesel, uma vez que este ácido somente é formado após o desencadeamento da auto-oxidação e, além do mais, esta espécie foi observada em amostras de biodiesel de diferentes origens (algodão, soja, palma e sebo bovido). Adicionalmente, métodos para a determinação de Cl-, SO4 2-, formiato, acetato, formaldeído e acetaldeído em etanol combustível são descritos. A separação foi realizada em BGE contendo 20 mmol L-1 de MES / L-histidina e 0,1 mmol L-1 hidróxido de cetiltrimetilamônio, pH 6. Para a separação dos aldeídos por CE, foi realizada a derivatização com bissulfito. O presente trabalho também apresenta um método alternativo para a determinação do teor de água e de álcool em amostras de etanol combustível. A estratégia descrita é baseada na formação de monoalquil carbonatos (MAC) produzidos pela reação de um álcool e o bicarbonato em meio aquoso. / In this work, methods employing capillary electrophoresis with capacitively coupled contactless conductivity detection (CE - C4D) are introduced for the determination of several species in biodiesel and ethanol fuel. The concentrations of inorganic species (Na+, K+, Ca2+, Mg2+, SO4 2-, and PO43-) and glycerol are of interest for the regulatory authorities due to their ability to form undesirable compounds in the engines. The separation of the cations was done in BGE composed of 30 mmol L-1 of 2-N-morpholino-ethanesulfonic acid (MES)/L-histidine, pH 6. The separation of anionic species was carried out in similar BGE including cetyltrimethylammonium bromide (0.2 mmol L-1). For glycerol, a neutral species, its oxidation with periodate was employed. This well-known reaction is specific to polyols and generates iodate. The amount of iodate produced by the reaction was determined by CE. The separation was carried out in ca. 1 min using BGE composed of 30 mmol L-1 of acetic acid, pH 3. This work also presents studies on the formation of low molecular organic acids during the biodiesel autoxidation step. Since the implications of the biodiesel oxidation are the increased viscosity and acidity, causing formation of insoluble gums and sediments that induce the clogging of the fuel filters. The samples were oxidized using equipment for accelerated oxidation test (Rancimat Method) and CE-C4D was used to analyze the ionic products. The main acid species were acetic and formic acids. However, acrylic, glyoxylic, glycolic, lactic, and propionic acids were also observed only after the oxidation step. Thus, these species are candidates for quality markers for biodiesel. In particular, glycolic acid seems to be a good marker, because it is produced only after auto-oxidation started. Moreover, it was found out in biodiesel of different origins (cotton, soy, palm, and animal fat). In addition, alternative methods to determination of Cl-, SO42-, formate, acetate, formaldehyde and acetaldehyde in ethanol fuel are described. The separation was done in BGE composed of 20 mmol L-1 of MES / L-histidine, and 0.1 mmol L-1 cetyltrimethylammonium hydroxide, pH 6. For aldehydes, a neutral species, a derivatization step with bisulfite was employed. The present work also shows an alternative method for analysis of alcohol and water percentage in fuel samples employing CE - C4D in order to achieve the limits established by regulatory authorities. The strategy is based on the formation of monoalkyl carbonates (MAC) produced by the reaction of an alcohol and bicarbonate in aqueous medium.

Deponering är globalt sett det vanligaste sättet att hantera avfall, men i Sverige får sedan 2001 enbart avfall som inte kan återanvändas deponeras. Innan deponiförordningen trädde i kraft 2001 deponerades många olika typer av avfall. En deponi används idag som ett slutförvar för avfall och för att minimera infiltration av regnvatten och eventuell föroreningsspridning sluttäcks gamla deponier. Sluttäckningen består av flera skikt som tillsammans ska täta deponin och leda bort vatten. Att förvara avfall i en sluttäckt deponi är miljöfarlig verksamhet och det är därför av intresse att kontrollera omgivningarna under och efter sluttäckning för att säkerställa att eventuell föroreningsspridning minskar. På Hovgårdens avfallsanläggning i Uppsala kommun har en deponi som använts sedan 1971 sluttäckts under hösten 2018. I två provtagningsrör vid deponin, i vilka provtagning och analys skett regelbundet sedan 1991, har förhöjda halter av vissa ämnen kunnat uppmätas efter att arbetet med sluttäckningen påbörjades. Syftet med detta examensarbete var att få ökad förståelse för trender i ämneshalter samt att utreda hur sluttäckning påverkar grundvattennivåer och ämneskoncentrationer runt deponin. Uppmätta halter i provtagningsrören sammanställdes och trender analyserades med statistiska verktyg i mjukvaran R. Dessutom konstruerades en grundvattenmodell över avfallsanläggningen i MODFLOW och MT3DMS. Stationära flödessimuleringar och transportsimuleringar med klorid utfördes. Tolv av 33 analyserade ämnen och parametrar uppvisar statistiskt signifikanta ökningar i antingen ett av provtagningsrören, båda eller båda analyserade tillsammans. Dessa är alkalinitet, elektrisk konduktivitet, sulfat, klorid, kalcium, natrium, svavel, kalium, magnesium, strontium, barium, och nitratkväve. Sex av dem minskar statistiskt signifikant och dessa är pH-värdet, kadmium, zink, kvicksilver, bly och arsenik. Grundvattenmodellen visar att grundvattnet under etapp 1 flödar mot resten av anläggningen men att flöden ut från deponin finns i de sydvästra och sydöstra hörnen. Sluttäckningen leder till lägre nivåer och en förändrad grundvattendelare vilket kommer minska läckaget, främst i den sydvästra delen. Modellsimuleringar med olika grundvattenbildningsmängder och kloridkoncentrationer visade att ökningar av kloridhalter inte kan förklaras med minskad grundvattenbildning i kombination med förhöjda koncentrationer. Förklaringen bör därmed vara andra fysikaliska och eventuellt kemiska processer som skett samtidigt som sluttäckningen. De parametrar som påverkade simulerade ämneshalter mest var konduktansen i diken och dränering samt moränens hydrauliska konduktivitet. / Landfills are globally the most common waste treatment method but in Sweden the method is since 2001 used only for waste that cannot be reused in any way. Before 2001, almost any type of waste could be landfilled. Today a landfill is used as a final storage and old landfills are capped to minimize infiltration and contaminant transport. A capping consists of several layers which together seal and drain the landfill surface. Storing waste in a capped landfill is considered an environmentally hazardous activity, therefore it is of great interest to monitor the surrounding groundwater during and after capping to make sure that any contaminant concentrations decreases. At Hovgården waste treatment plant in Uppsala, Sweden, a landfill used since 1971 was capped during 2018. Elevated contaminant concentrations have been measured in two monitoring wells close to the landfill after the capping procedure started. The aim of this master thesis was to increase the understanding of trends in contaminant concentrations and to investigate how capping affects groundwater levels and concentrations. Concentration data were compiled and statistical tools in R were used to analyze trends. Additionally, a groundwater model of the area was created in MODFLOW and MT3DMS. The model was used to simulate different steady state scenarios with and without chloride transport. Twelve of 33 analyzed substances and parameters show a statistically significant increase. These are alkalinity, electrical conductance, sulphate, chloride, calcium, sodium, sulfur, potassium, magnesium, strontium, barium and nitrate. Six show a decrease, these are pH, cadmium, zinc, mercury, lead and arsenic. The groundwater model indicates that the groundwater flow in the landfill is directed towards the rest of the waste treatment plant except for two places where leakage occurs: the southwest and southeast corners of the landfill. The capping results in lower groundwater levels and an altered groundwater divide, which will reduce the contaminant leakage, particularly in the southwest part. Model simulations with varying recharge and chloride concentrations showed that the increase in chloride levels cannot be explained with only decreased infiltration combined with increased concentrations. Therefore, the explanation is assumed to be other physical processes and possibly chemical reactions due to or at the same time as the capping. The model parameters that effected the simulated concentrations to the greatest extent are the conductances in drains, and the hydraulic conductivity of the till soil.