D. Tech. Chemistry / The increase in industrialisation in South Africa has led to an increase in coal mining and coal utilisation in Mpumalanga. This has resulted in the deterioration in the quality of water upstream of Loskop Dam. Little or no information is available on the occurrence or fractionation of trace metals in sediments, which are reservoirs for pollutants. Furthermore, no information is available concerning the occurrence of polycyclic aromatic hydrocarbons (PAHs), known for their carcinogenic and mutagenic effects, in rivers in the area. The possible impact of leaching of elements and organic compounds from South African coals has not been exhaustively researched. The general objectives of the study were to: 1) assess the impact of potentially toxic metals and organic compounds leaching from coal, on the quality of surface waters via simulated leaching experiments; 2) determine the extent of pollution by trace metals and polycyclic aromatic hydrocarbons of the Olifants, Klein Olifants and Wilge rivers, at selected points in the upper catchment area; and 3) identify and apportion sources of polycyclic aromatic hydrocarbons in the sediment samples from the study area.

No description available.

Motivation: The accurate and reliable measurement of the concentration of coal tar pitch volatiles (CTPVs) in ambient air has proved to be a challenge for occupational hygienists. The challenge must however be confronted due to, amongst others, the carcinogenic properties of some poly–aromatic hydrocarbons (PAHs) contained in CTPVs. Aim: To determine the feasibility of a thermal desorption (TD) technique based method as an alternative method to be used for the measurement of the concentration of CTPVs in ambient air by assessing it along criteria such as ease of use, cost, accuracy and precision by comparing it to NIOSH’s Method 5515 and OSHA’s Method 58 and to determine the level of exposure to CTPVs on the anode paste floor of an electric furnace, used for the smelting of platinum group metals (PGMs) concentrate. Methodology: To satisfy the research objective, two accepted methods the National Institute of Occupational Safety and Health’s (NIOSH) method 5515 and the Occupational Safety and Health Administration’s (OSHA) method 58 were used for the measurement of the concentration of CTPVs with a TD technique based method used as a third, alternative method. All three methods were used concurrently to measure the concentration of CTPVs in ambient air, at the anode paste floor of a platinum group metals (PGMs) concentrate smelter. Results and conclusions: The NIOSH method proved to be the most precise method while the TD technique based method proved to be the most accurate. The TD technique based method proved to measure the widest range of individual CTPVs and were able to measure the highest concentration of Benzo(a)pyrene, an individual CTPV that is classified as a Group 1 (carcinogenic to humans) chemical substance by the International Agency for Research on Cancer (IARC). The OSHA method measured on average almost four times less total CTPVs than either the NIOSH or the TD technique based method and failed to readily measure individual CTPVs with a molecular weight lower than that of Phenanthrene. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2012.

Motivation: The accurate and reliable measurement of the concentration of coal tar pitch volatiles (CTPVs) in ambient air has proved to be a challenge for occupational hygienists. The challenge must however be confronted due to, amongst others, the carcinogenic properties of some poly–aromatic hydrocarbons (PAHs) contained in CTPVs. Aim: To determine the feasibility of a thermal desorption (TD) technique based method as an alternative method to be used for the measurement of the concentration of CTPVs in ambient air by assessing it along criteria such as ease of use, cost, accuracy and precision by comparing it to NIOSH’s Method 5515 and OSHA’s Method 58 and to determine the level of exposure to CTPVs on the anode paste floor of an electric furnace, used for the smelting of platinum group metals (PGMs) concentrate. Methodology: To satisfy the research objective, two accepted methods the National Institute of Occupational Safety and Health’s (NIOSH) method 5515 and the Occupational Safety and Health Administration’s (OSHA) method 58 were used for the measurement of the concentration of CTPVs with a TD technique based method used as a third, alternative method. All three methods were used concurrently to measure the concentration of CTPVs in ambient air, at the anode paste floor of a platinum group metals (PGMs) concentrate smelter. Results and conclusions: The NIOSH method proved to be the most precise method while the TD technique based method proved to be the most accurate. The TD technique based method proved to measure the widest range of individual CTPVs and were able to measure the highest concentration of Benzo(a)pyrene, an individual CTPV that is classified as a Group 1 (carcinogenic to humans) chemical substance by the International Agency for Research on Cancer (IARC). The OSHA method measured on average almost four times less total CTPVs than either the NIOSH or the TD technique based method and failed to readily measure individual CTPVs with a molecular weight lower than that of Phenanthrene. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2012.

19 Dec 2004. / Published through the Information Bridge: DOE Scientific and Technical Information. "IS-T 1944" Lisa M. Ponton. 12/19/2004. Report is also available in paper and microfiche from NTIS.

Made available in DSpace on 2015-04-17T14:49:12Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1477687 bytes, checksum: 499775300ecca263fde140f8d1c98bb3 (MD5) Previous issue date: 2010-09-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The aim of this work was to evaluate the PAHs contamination in muscular tissue and bile of Mugil liza fishes from Guanabara Bay. The Guanabara Bay is an estuarine ecosystem with high anthropogenic influence which receives chronic pollution from Rio de Janeiro city. It was determined 38 compounds (16 PAHs EPA + alkylated ones) in muscular tissue samples of 41 fishes captured from August 2008 to October 2008. Statistical analyzes showed that the data concentration has a normal distribution and drawn from the same population, with mean concentration of 127 ng/g and standard deviation of 18 ng/g to the 16 PAHS EPA. The mean concentration for the 38 compounds was 274 ng/g and standard deviation of 59 ng/g. It was determinated 13 metabolites of PAHs of 30 Mugil liza fishes (n=30) captured in the inner part of the Guanabara Bay. The metabolites determined were OH-Naphthalenes, OH-Biphenyl, OH-Fluorene, OH-Phenantrenes, OH-Pyrene, OH-Chrysene, OH-Benz(a)pyrene. It was observed in this study a normal distribution of concentrations for both set of data: bile PAH metabolites and PAH muscular tissue. This indicates the existence of two data populations. The mean concentration of PAH metabolites obtained was 1,039 ng/g and standard deviation of 624 ng/g. These data can be used as back ground to the inner part of Guanabara Bay. The bioindicator in this study, Mugil liza fish, has shown to be effective to evaluate the contamination and exposition of Guanabara Bay ecosystem to PAH. / Este trabalho teve como objetivo a avaliação da contaminação por HPAs em peixes provenientes da Baía de Guanabara através da identificação e quantificação desses compostos em tecido muscular e de seus metabólitos em bile. A Baía de Guanabara é um ecossistema estuarino de forte influência antropogênica que recebe poluição crônica da região metropolitana do Rio de Janeiro. Foram analisados 41 amostras de peixes da espécie Mugil liza (Tainha) coletados na Baía de Guanabara no período de agosto a outubro de 2008. Nos tecidos musculares foram quantificados 38 compostos (16 HPAs EPA e seus respectivos alquilados). A análise estatística revelou que esse grupo de dados é proveniente de uma mesma população com distribuição normal, com valor médio de concentração de 127 ng/g e desvio-padrão populacional de 18 ng/g para o Σ 16 HPAs e concentração média populacional para o Σ 38 HPAs de 274 ng/g e desvio-padrão de 59 ng/g. Em sequência, foi realizada a avaliação do nível de exposição a que os organismos aquáticos da Baía de Guanabara estão submetidos, através da análise de 30 amostras de bile de peixes da espécie Mugil Liza provenientes de currais da área de fundo da Baía de Guanabara, onde foram quantificados 13 metabólitos individuais de HPAs. Os metabólitos determinados foram 1-OH-Naftaleno, 2-OH-Naftaleno, 2-OH-Bifenila, 3-OH-Fluoreno, 1-OH-Fenantreno, 2-OH-Fenantreno, 3-OH-Fenantreno, 4-OH-Fenantreno, 9-OH-Fenantreno, 1-OH-pireno, 1-OH-criseno, 3-OH-benzo(a)pireno e 9-OH-benzo(a)pireno. O valor médio de concentração do somatório dos metabólitos foi de 1.039 ng/g e desvio-padrão populacional de 623 ng/g. Esses dados podem ser utilizados como valores característicos para a região já que apresentaram uma distribuição normal. As concentrações determinadas encontraram-se dentro da faixa de outras regiões com influência antropogênica elevada, com aporte crônico de hidrocarbonetos. O bioindicador utilizado neste estudo, o peixe da espécie Mugil liza, mostrou-se efetivo para a avaliação da contaminação por HPAs em um ecossistema como a Baía de Guanabara.

Orientador: Luiz Carlos da Silva Filho / Resumo: A reação de acilação de Friedel-Crafts é uma das mais importantes reações de formação de ligações carbono-carbono em compostos aromáticos. As reações de acilação de Friedel-Crafts ocorrem basicamente por meio da reação entre compostos aromáticos com haletos de acila ou anidridos na presença de um ácido de Lewis. Assim, neste trabalho foi estudado o uso do pentacloreto de nióbio como ácido de Lewis nas reações de acilação de Friedel-Crafts visando à síntese de corantes sensibilizadores. Os derivados de fluoresceína foram sintetizados a partir de derivados fenólicos e derivados de anidrido, na presença de NbCl5 e sob aquecimento. Os produtos de interesse foram obtidos com rendimentos de 54 a 90% e em curtos tempos reacionais que variaram de 50 a 200 minutos. As fluoresceínas apresentaram absorção e emissão de luz dentro do comprimento de onda do visível, com alta intensidade e altos valores de rendimento quântico de fluorescência (0,60 a 0,93) quando dissolvidos em soluções alcalinas. Os derivados de fluoresceínas foram aplicados na confecção de células solares de Gratzel apresentando eficiências de conversão que variaram de 0,11 a 0,23%. Também foi estudado a aplicação dos derivados de fluoresceínas como corantes iniciadores em reações de fotopolimerização de resinas de dimetacrilato. Estas resinas tem sido largamente utilizadas na odontologia, devido as suas propriedades como baixa toxicidade, baixa solubilidade em água e alta resistência mecânica. As fluoresceínas promoveram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Friedel-Crafts acylation reaction is one of the most important reactions for the formation of carbon-carbon bonds. The Fridel-Crafts acylation reaction occurs basically by a reaction between aromatic compounds with acyl halides or anhydrides in the presence of a Lewis acid. Thus, in this work it was studied the use of niobium pentachloride as Lewis acid in Friedel-Crafts acylation reaction, aiming the synthesis of sensitizing dyes. The fluorescein derivatives were synthesized from phenolic derivatives and anhydride derivatives, in the presence of NbCl5 and under heating. The products of interest where obtained in yields of 54 to 90% and in short reaction times ranging from 50 to 200 minutes. The fluorescein derivatives presented absorption and emission within the range of visible and with high intensity and high fluorescence quantum yield (0,60 to 0,93) when dissolved in alkaline pH. Due to these good results obtained in the photophysical study, the fluorescein derivatives were applied in Gratzel solar cells, presenting convertion efficiencies that ranging from 0.11 to 0.23%. It has also been studied the application of fluorescein derivatives as initiator dyes in photopolymerization reactions of dimethacrylated resins. This resins have been widely used in dentistry, due this properties as, low toxicity, low solubility in water and high mechanical resistance. The fluoresceins promoted the photopolymerization of dimethacrylated resins with conversion values ranging from 1.2... (Complete abstract click electronic access below) / Doutor

As nanopartículas atmosféricas podem causar diversos efeitos à saúde já que durante a inalação podem penetrar mais profundamente no sistema respiratório humano, atingindo inclusive os alvéolos e a corrente sanguínea, e, desta forma, aumentar os efeitos toxicológicos prejudiciais. Estas partículas podem ser emitidas diretamente para a atmosfera (partículas primárias) ou ser formadas por conversão gás-partícula (partículas secundárias). Durante a última década, estudos têm sido realizados para uma melhor compreensão sobre as concentrações de nanopartículas, avaliando sua emissão, formação, dispersão, exposição e os efeitos à saúde. No entanto, poucos estudos foram realizados no Brasil e desta forma ainda há pouca informação em relação a esta temática. A Região Metropolitana de Porto Alegre - RMPA (Brasil) possui forte tráfego veicular, cerca de 1,8 milhões de veículos e, apesar das fontes móveis impactarem fortemente a qualidade do ar nesta região e ser a principal fonte de nanopartículas, não há estudos que avaliem em profundidade os níveis deste importante poluente ambiental. Desta forma, no presente estudo foram avaliadas as concentrações de nanopartículas em diferentes pontos da RMPA. Além disso, foram avaliadas as concentrações ambientais de partículas <1 μm (MP1) e metais associados, bem como foram identificadas e quantificadas as contribuições de fontes utilizando o modelo receptor Positive Matrix Factorization (PMF). Em adição, foi realizada uma análise das assinaturas espectrais no infravermelho de nitro-hidrocarbonetos policíclicos aromáticos (nitro-HPAs) associados ao MP1. Este grupo de compostos orgânicos possui uma ampla distribuição no ambiente e, por possuírem propriedades mutagênicas e carcinogênicas, seus riscos ambientais foram calculados. Desta forma, considerando os resultados obtidos, verificou-se uma forte contribuição antropogênica dos poluentes avaliados na RMPA. Esta degradação da qualidade do ar está em geral associada ao tráfego veicular, especialmente no que se refere aos níveis de nanopartículas e nitro-HPAs associados ao MP1. Além disso, as emissões industriais, a queima de carvão, biomassa e óleo combustível, bem como a queima de combustíveis veiculares apresentaram forte influência nos níveis de metais observados em MP1. / Atmospheric nanoparticles can cause health effects, as during inhalation penetrate more deeply into the human respiratory system, including the alveoli and reaching the bloodstream, and thereby increase the damaging toxicological effects. These particles can be emitted directly to the atmosphere (primary particles) or be formed by gas-to-particle conversion (secondary particle). Over the last decade, studies have been conducted for a better understanding of the nanoparticles, assessing the emission, formation, dispersion, exposure and health effects. However, few studies have been conducted in Brazil and thus there is little information regarding this subject. The Metropolitan Area of Porto Alegre - MAPA (Brazil) has a strong vehicular traffic, about 1.8 million vehicles and, despite mobile sources strongly impact the air quality in this region and be the main source of nanoparticles, there are no studies that evaluate in depth the levels of this important environmental pollutant. Thus, considering this knowledge gap, the present study evaluated the nanoparticle concentrations in different sites of the MAPA. In addition, environmental concentrations of particles <1 μm (MP1) and associated metals were evaluated and the sources were identified and quantified using the receptor model Positive Matrix Factorization (PMF). In addition, an analysis of the infrared spectral signatures of nitro polycyclic aromatic hydrocarbons (nitro-PAHs) associated with PM1 was performed. This group of organic compounds has a wide distribution in the environment, and because they have mutagenic and carcinogenic properties, their environmental risks were calculated. Thus, considering the obtained results, a strong anthropogenic contribution of the evaluated pollutants in the MAPA was observed. This degradation of the air quality in general is associated with vehicular traffic, especially regarding the levels of nanoparticles and nitro-PAHs associated with PM1. In addition, industrial emissions, coal, biomass and fuel oil combustion, as well as vehicle fuels combustion had a strong influence on the metal levels observed in PM1.

Les sols contaminés par les polluants organiques hydrophobes tels que les Hydrocarbures Aromatiques Polycycliques (HAPs) constituent un problème majeur puisqu'ils sont difficilement éliminés et leurs impacts toxicologiques restent significatifs. Comme alternative aux procédés thermiques et physiques traditionnels, les procédés de lavages de sol in situ et ex situ apparaissent être une solution envisageable et efficace et particulièrement pour les fortes pollutions. Cependant, le traitement des solutions fortement chargées de lavages de sol est une autre barrière à surmonter. Une nouvelle approche combinée est proposée pour répondre à ce problème: les procédés de lavages de sol in situ/ex situ combinés à un Procédé Electrochimique d'Oxydation Avancée Electrochimique (PEOA) avec possibilité de recirculer l'effluent (pour réutiliser l'agent extractant) et/ou de combiner avec un post-traitement biologique (pour minimiser le coût énergétique).L'efficacité d'extraction de l'agent extractant tel que l'hydroxypropyl-beta-cyclodextrine (HPCD) est comparé au traditionnel tensioactif non-ionique dénommé Tween 80, dans les solutions synthétiques et réelles de lavages de sol. Une nouvelle méthode sensible d'analyse du Tween 80, basée sur la fluorescence, est développée pour suivre l'oxydation du Tween 80. Deux PEOAs sont comparés : l'électro-Fenton (EF) et l'oxydation anodique (OA). Les anodes de platine (Pt) (dans le procédé EF) et de diamant dopés au bore (BDD) (dans les deux procédés) sont respectivement utilisées pour étudier la recirculation des effluents et la possibilité d'une combinaison avec un post-traitement biologique. Concernant la réutilisation des agents extractants, l'évolution de la biodégradabilité des solutions et l'énergie consommée (en kWh (kg COT)-1) pendant les PEAOs testés, l'HPCD est trouvée être plus avantageuse que le Tween 80. En revanche, en terme d'efficacité d'extraction, de coût des agents extractants et d'impact sur la respirométrie du sol, le Tween 80 paraît être plus avantageux. En prenant en compte tous ces avantages et inconvénients, le Tween 80 pourrait être retenu comme la meilleure solution / Soils contaminated by hydrophobic organic pollutants like polycyclic aromatic hydrocarbons (PAHs) are a common concern since they are extremely difficult to remove and their potential toxicological impacts are significant. As an alternative to traditional thermal or physical treatments, soil washing and soil flushing processes appear to be conceivable and efficient approaches, especially for higher level of pollution. However, the treatment of highly loaded soil washing/flushing solutions is another challenge to overcome. In that way, a new integrated approach is suggested: soil washing/flushing processes combined to an electrochemical advanced oxidation process (EAOP) in a combination with a recirculation loop (to save extracting agents) and/or a biological post-treatment step (to minimize energy cost).Extraction efficiency of the extracting agent like hydroxypropyl-beta-cyclodextrin (HPCD) is compared to the traditional non-ionic surfactant Tween 80 in synthetic and real soil washing solutions. A new simple fluorescent sensitive and selective quantification method is developed to monitor Tween 80 oxidation. Two EAOPs were compared: electro-Fenton (EF) and anodic oxidation (AO). Platinum (Pt) (in EF process) and boron doped diamond (BDD) (in both treatment) anodes are the respective electrodes employed to recycle effluents and to consider a biological post-treatment, respectively. Regarding the extracting agent recovery, the biodegradability evolution of effluent and the energy consumption (in kWh (kgTOC)-1) during EAOP, HPCD is more advantageous than Tween 80. However, in terms of extraction efficiency, costs of extracting agents and impact on soil respirometry, Tween 80 is much more efficient. By considering all these advantages and drawbacks, Tween 80 could still appear to be the best option

A concentração de Fe, Ni, Cd, Mn, Zn, Cr e Pb, determinada por TXRF, foi investigada em matrizes de água, sedimento e fígados de peixes, amostrados em rios da região mineradora de carvão de Criciúma - SC/Brasil - afetadas por descargas de drenagem ácida de mina (DAM). A relação destes metais com a toxicidade para o bioindicador Daphnia magna (24 e 48 h) foi avaliada, sendo estabelecida correlação entre [Fe]solúvel e toxicidade à D. magna nas amostras de água. Para os sedimentos, há indícios de correlação dos teores de Fe e toxicidade, e nos fígados suspeita-se de níveis de Zn alterados. Efluentes da mineração, incluindo a DAM, após o tratamento por floculação e/ou decantação e/ou flotação e alcalinização mantiveram toxicidade mesmo com os metais reduzidos para concentrações não tóxicas à D. magna. Creditou-se a toxicidade remanescente a hidrocarbonetos policíclicos aromáticos (HPAs, determinada por CG/MS). Foram testados três adsorventes de baixo custo na retenção de metais (Fe, Ni, Cd, Mn, Zn, Cr e Pb) em soluções ácidas multimetais: casca de arroz (CA), carvão de casca de arroz (CCA) e turfa e carvão ativado comercial (CAC – adsorvente de confronto). As quantidades máximas adsorvidas dos metais (mg) por massa de sorbente (g) - qm, somatório dos metais, foram: CA 75,46 mg g-1; CAC 78,2 mg g-1; turfa 111,3 mg g-1 e CCA 137,49 mg g-1, (Langmuir e Freundlich - não linear). A toxicidade dos metais para D. magna destes eluatos foi reduzida. Foram preparados compósitos a partir de casca de arroz com deposição in situ de TiO2 (CCT – carbon covered with titanium), e testados como catalisador em Processos Oxidativos Avançados (POA). Os catalisadores TiO2 (P25 Degussa) e CCTs (25 e 50% de TiO2) em POA mostraram remoção dos HPAs e da toxicidade (D. magna e Scenedesmus subspicatus) nos efluentes de mineração, adequando os níveis de toxicidade à legislação ambiental vigente (Portaria FATMA 017/02) com resultados superiores do CCT. Assim, a presente tese alega que o uso de adsorventes à base de carvão de casca de arroz é capaz de reter os metais tipicamente presentes em efluentes ácidos (mineração de carvão), e que a toxicidade remanescente nestes efluentes, devida aos HPAs, pode ser reduzida pelo uso de POA, com incremento de eficiência quando o compósito CCT aqui desenvolvido é utilizado. / The concentration of Fe, Ni, Cd, Mn, Zn, Cr and Pb, determined by TXRF, was investigated in matrixes as water, sediment and fish liver, sampled at mining of coal region rivers from Criciúma - SC/Brazil – targets by acid mine drainage (ADM) discards. The relation of these metals with toxicity to Daphnia magna bioindicator (24 and 48 h) was evaluated, being established a correlation between [Fe]soluble and toxicity to D. magna in water samples. In sediments, correlation between Fe levels and toxicity was observed, and in liver Zn levels were altered. Mining effluents including AMD, after treatment by flocculation and/or decantation and/or flotation and alkalinization remain toxic even when metal concentrations had been reduced to levels which would be non toxic to D. magna. Residual toxicity was accounted to the presence of polycyclic aromatic hydrocarbons (PAHs, determined by GC/MS). Three low cost adsorbents were tested in metal retention (Fe, Ni, Cd, Mn, Zn, Cr and Pb) from multielemental acid solution: rice husk (RH), rice husk carbon (RHC), peat and commercial activated carbon (CAC – confront adsorbent). The maximum quantity of adsorbed metals (mg) by sorbent mass (g) - qm, as metals sum, were: CA 75.46 mg g-1; CAC 78.2 mg g-1; peat 111.3 mg g-1 and CCA 137.49 mg g-1, (Langmuir and Freundlich – non linear). The metal toxicity to D. magna of these eluates was reduced. Composites from rice husk with in situ deposition of TiO2 were synthesized (CCT – carbon covered with titanium), and tested as catalyst in advanced oxidative process (AOP). The catalysts TiO2 (P25 Degussa) and CCTs (25 e 50% de TiO2) in AOP showed PAHs and toxicity remotion (D. magna and Scenedesmus subspicatus) on mining effluents, adjusting toxicity levels to environmental legislation in force (FATMA 017/02), with best results to CCT. Then, the present thesis argues that rice husk carbon adsorbents is capable of retaining the metals typically presents in acid effluents (coal mining), and that remain toxicity in these effluents, from PAHs, can be reduced by AOP use, with efficient increasing when the composite here developed (CCT) is employed.