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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Comparative toxicity and bioavailability of heavy fuel oils to fish using different exposure scenarios

Martin, Jonathan 25 July 2011 (has links)
Heavy fuel oils (HFO) are produced from the refining of crude oils, and have high specific gravities and high viscosities. In recent years, spills of HFO have increased in the environment, and are of great concern because they are difficult to clean up. Spilled HFO is likely to become submerged, and can become stranded if fresh HFO coats benthic substrates or if weathered HFO sinks as tarballs. Conversely, lighter oils float on the surface and their components disperse and become diluted in the water column. There is a research need to assess the unique ecological risks of HFO that can sink and contaminate spawning shoals of fish. Chronic toxicity of HFO to fish embryos is correlated with exposure to polycyclic aromatic hydrocarbon (PAH) that become bioavailable from spilled HFO to identify under which spill conditions fish populations are at greatest risk. The results of this research demonstrate that: (1) Stranded HFO is a significant source of PAH to the receiving environment and causes chronic toxicity to embryonic fish; (2) Tarballs and weathered HFO cause less toxicity than fresh HFO, likely a consequence of physical limitations to PAH release; (3) HFO 7102 samples collected from an HFO spill in Wabamun Lake, Alberta, are less toxic than HFO 6303; (4) HFO is at least 2-fold more toxic than Medium South American (MESA), a well-studied reference crude oil, coincident with 3-fold higher concentrations of alkyl PAH, namely alkyl phenanthrenes. / Thesis (Master, Biology) -- Queen's University, 2011-07-25 10:43:05.759
2

Use of Rainbow Trout Liver Cell Line (RTL-W1) to evaluate the toxicity of Heavy Fuel Oil 7102

Chen, Ci January 2013 (has links)
A rainbow trout liver cell line, RTL-W1, was used to evaluate the toxic potential of a heavy fuel oil (HFO) HFO 7102, and its fractions, which together with the HFO are referred to as the oil samples. The fractions were F2, F3, F3-1, F3-2 and F4 and had been prepared by low-temperature vacuum distillation by collaborators at Queen's University. For presentation to the cells, HFO 7102 and its fractions were made into High Energy-Chemically Enhanced Water Accommodated Fractions (HE-CEWAFs). The procedure for this involved adding Corexit 9500 to the oil samples, mixing them on a vortex, and letting the phases settle. The HE-CEWAFs were added to RTL-W1 cell cultures, and at various times afterwards cell viability and CYP1A induction were monitored. Cell viability was evaluated with two dyes, Alamar Blue, which monitors energy metabolism, and 5-carboxfluorescein diacetate acetoxymethyl ester (CFDA AM), which measures plasma membrane integrity. With both indicator dyes, Corexit 9500 was cytotoxic but the concentrations eliciting cytotoxicity varied with the cell culture media. In Leibovitz's L-15 with fetal bovine serum (FBS), which was the medium used for studying CYP1A induction, Corexit 9500 was only cytotoxic at concentrations of 0.1 % (v/v) and greater. For the oil samples, F3-2 at 1 mg/ml and F4 at 10 mg/ml, which were the highest testable concentrations for each, no loss of cell viability was observed over 24 h. The other oil samples were cytotoxic only at their highest testable concentrations, which ended being between 1 and 10 mg/ml. CYP1A induction was monitored in RTL-W1 as catalytic activity and as the level of CYP1A (P4501A) protein. The catalytic activity was assayed as 7-ethoxyresorufin o-deethylase (EROD) activity; the CYP1A protein level, by western blotting. The positive control was 2, 3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), which strongly induced both EROD activity and CYP1A protein. Corexit 9500 by itself neither induced EROD activity nor CYP1A protein. All the oil samples induced both EROD activity and CYP1A protein. With both endpoints, the most potent fraction was F3; the least potent, F3-2. As the induction of CYP1A is associated with the development of blue sac disease (BSD) and mortality in early life stages of fish, the results suggest that HFO 7102 and its fractions have the potential to reduce recruitment of young into adult fish populations. CYP1A induction by F3 was studied further, again through EROD activity and western blotting. As the F3 concentration was increased, EROD activity increased but declined at high concentrations, whereas CYP1A protein continued to increase. This suggests the presence of compounds in F3 that at high concentrations inhibit the catalytic activity of CYP1A. When F3 was presented to RTL-W1 cultures together with TCDD, CYP1A protein was induced but not EROD activity. Again this suggests that F3 contains inhibitor(s) of CYP1A as well as inducers. When cultures were exposed to either F3 or TCDD for 24 h and then followed by western blotting for up to 6 days after F3 or TCDD removal, CYP1A levels declined in F3 cultures but not in TCDD cultures. This suggests that RTL-W1 were able to inactivate CYP1A inducer(s) in F3 through metabolism. Overall the results suggest that the pattern of CYP1A induction by F3, and by extension, HFO involves complex interactions between the many chemical components in these mixtures. Likely the most important chemicals are the polycyclic aromatic hydrocarbons (PAHs).
3

Application of Fenton-like technique to remediate fuel-oil contaminated soils

Liang, Shu-hao 29 August 2006 (has links)
Soil and groundwater at many existing and former industrial areas and disposal sites is contaminated by petroleum hydrocarbons that were released into the environment. Among those petroleum hydrocarbons, fuel oil is more difficult to treat compared to gasoline and diesel fuel due to its characteristics of low volatility, low biodegradability, and low mobility. Thus, a combination of several different treatment technologies is required to remediate fuel oil contaminated soil or groundwater. The objective of this study was to assess the potential of applying Fenton-like oxidation process to remediate fuel-oil contaminated soils. The following tasks were performed in this study: (1) determination of the optimal oxidation conditions, (2) evaluation of the efficiency of chemical by Fenton-like process after the pretreatment of surfactant flushing, and (3) evaluation of the stability of H2O2 by the addition of potassium dihydrogen phosphate (KH2PO4). Total petroleum hydrocarbons (TPH) in soil were analyzed to determine the effectiveness of the oxidation treatment. Results from this study show that the highest TPH removal efficiency (84.8%) was obtained for soils containing 3%(w/w) of fuel oil when 3% of H2O2 was applied followed by 0.05% of H2O2 with 56.7% of TPH removal. Results also show that approximately 69.1% of TPH removal was detected with soils containing 5%(w/w) of fuel oil when 6% of H2O2 was applied followed by 3% of H2O2 with 56.7% of TPH removal and 0.05% of H2O2 with 32.6% of TPH removal. Results also indicate that Fenton-like process has much higher oxidation efficiency than using H2O2 alone. The oxidation efficiency was significantly affected when the contaminated soils were pretreated with surfactant. Results reveal that the maximum allowable surfactant addition was approximately 0.7% (w/w) for soils containing 0.5% (w/w) of fuel oil when 6% of H2O2 was applied. Addition of 2.2 mM of potassium dihydrogen phosphate influence could increase the stability of H2O2, but caused the decrease in the efficiency of TPH removal. During the Fenton-like reaction, pH values were close to 6 to 7. The neutral to slightly acidic conditions caused the decreased dissolution rate of iron minerals. This would also cause the decreased production of hydroxyl radicals from the surface of iron minerals. Results from the byproduct analysis show that the oxidation potential of Fenton-like process is not strong enough to completely destroy the fuel oil to non-toxic end products. The oxidation process produced byproducts containing carboxyl groups with molecular weights similar to their parent compounds.
4

Use of Rainbow Trout Liver Cell Line (RTL-W1) to evaluate the toxicity of Heavy Fuel Oil 7102

Chen, Ci January 2013 (has links)
A rainbow trout liver cell line, RTL-W1, was used to evaluate the toxic potential of a heavy fuel oil (HFO) HFO 7102, and its fractions, which together with the HFO are referred to as the oil samples. The fractions were F2, F3, F3-1, F3-2 and F4 and had been prepared by low-temperature vacuum distillation by collaborators at Queen's University. For presentation to the cells, HFO 7102 and its fractions were made into High Energy-Chemically Enhanced Water Accommodated Fractions (HE-CEWAFs). The procedure for this involved adding Corexit 9500 to the oil samples, mixing them on a vortex, and letting the phases settle. The HE-CEWAFs were added to RTL-W1 cell cultures, and at various times afterwards cell viability and CYP1A induction were monitored. Cell viability was evaluated with two dyes, Alamar Blue, which monitors energy metabolism, and 5-carboxfluorescein diacetate acetoxymethyl ester (CFDA AM), which measures plasma membrane integrity. With both indicator dyes, Corexit 9500 was cytotoxic but the concentrations eliciting cytotoxicity varied with the cell culture media. In Leibovitz's L-15 with fetal bovine serum (FBS), which was the medium used for studying CYP1A induction, Corexit 9500 was only cytotoxic at concentrations of 0.1 % (v/v) and greater. For the oil samples, F3-2 at 1 mg/ml and F4 at 10 mg/ml, which were the highest testable concentrations for each, no loss of cell viability was observed over 24 h. The other oil samples were cytotoxic only at their highest testable concentrations, which ended being between 1 and 10 mg/ml. CYP1A induction was monitored in RTL-W1 as catalytic activity and as the level of CYP1A (P4501A) protein. The catalytic activity was assayed as 7-ethoxyresorufin o-deethylase (EROD) activity; the CYP1A protein level, by western blotting. The positive control was 2, 3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), which strongly induced both EROD activity and CYP1A protein. Corexit 9500 by itself neither induced EROD activity nor CYP1A protein. All the oil samples induced both EROD activity and CYP1A protein. With both endpoints, the most potent fraction was F3; the least potent, F3-2. As the induction of CYP1A is associated with the development of blue sac disease (BSD) and mortality in early life stages of fish, the results suggest that HFO 7102 and its fractions have the potential to reduce recruitment of young into adult fish populations. CYP1A induction by F3 was studied further, again through EROD activity and western blotting. As the F3 concentration was increased, EROD activity increased but declined at high concentrations, whereas CYP1A protein continued to increase. This suggests the presence of compounds in F3 that at high concentrations inhibit the catalytic activity of CYP1A. When F3 was presented to RTL-W1 cultures together with TCDD, CYP1A protein was induced but not EROD activity. Again this suggests that F3 contains inhibitor(s) of CYP1A as well as inducers. When cultures were exposed to either F3 or TCDD for 24 h and then followed by western blotting for up to 6 days after F3 or TCDD removal, CYP1A levels declined in F3 cultures but not in TCDD cultures. This suggests that RTL-W1 were able to inactivate CYP1A inducer(s) in F3 through metabolism. Overall the results suggest that the pattern of CYP1A induction by F3, and by extension, HFO involves complex interactions between the many chemical components in these mixtures. Likely the most important chemicals are the polycyclic aromatic hydrocarbons (PAHs).
5

Identification of compounds in heavy fuel oil 7102 that are chronically toxic to rainbow trout (Oncorhynchus mykiss) embryos

Adams, Julie 24 January 2013 (has links)
Spilled heavy fuel oil (HFO) sinks within the water column and accumulates in sediments, affecting aquatic organisms that are not typically exposed to oils that float. Previously, the 3-4 ring alkyl substituted polycyclic aromatic hydrocarbons (PAHs) have been identified as the major toxic components in crude oil. Since HFO is comprised of higher concentrations of 3-4 ringed alkyl PAH and an abundance of 5-6 ringed PAH relative to crude oil, it is predicted to be more toxic to the early life stages of fish. An effects-driven chemical fractionation (EDCF) of HFO 7102 was undertaken to establish the toxicity relative to crude oil, and to identify the compounds that are bioavailable and chronically toxic to the early life stages of fish. In this EDCF, the complex HFO 7102 mixture was separated by low temperature vacuum distillation into three distinct fractions, 2, 3 and 4. Each fraction was assessed using a chronic bioassay to determine whether it contained components that caused toxicity to rainbow trout embryos similar to that of the whole oil. Acute bioassays with juvenile trout demonstrated the presence of compounds that induce cytochrome P450 enzymes, an indicator of exposure to PAH. Fraction 3, the fraction more toxic than the parent mixture, was further separated by cold acetone extraction into fraction 3-1 (PAH-rich extract) and fraction 3-2 (wax residue), and assessed with the same bioassays. Simultaneous chemical analysis with bioassays guided the fractionation, and identified compounds abundant and consistently present in toxic fractions. Due to resistance to dispersion of HFO, a chemical dispersant was used with vigorous mixing to drive the maximum amount of oil into solution to minimize the potential for false negatives and the volume of test material used. The potency of HFO 7102 and its fractions were also measured using water accommodated fractions (WAFs) produced by a continuous flow system of water flowing through oil coated gravel. Both exposure methods traced the toxicity from whole oil into fractions containing higher concentrations of 3-4 ring alkyl PAH, similar to crude oil. This research is the first toxicological assessment of HFO 7102, which is essential for determining the risk of spills of HFO to fish, and whether the risk of oils can be predicted from their alkyl PAH composition. / Thesis (Master, Biology) -- Queen's University, 2013-01-24 14:14:16.278
6

Effects-Driven Fractionation of Heavy Fuel Oil to Isolate Compounds Toxic to Trout Embryos

Bornstein, Jason 09 August 2012 (has links)
Heavy Fuel Oil (HFO) is a petroleum product and emerging contaminant used as fuel by cargo ships, cruise liners, and oil tankers. As a high-frequency, low volume commodity shipped by pipeline, train, truck, and ship, it is at high risk for small-scale spills in terrestrial, aquatic, and marine environments. There are few reports characterizing HFOs and quantifying the contaminants therein, but previous studies have shown that the most toxic classes of compounds in petroleum products are polycyclic aromatic hydrocarbons (PAHs). This project seeks to address that by analyzing HFO 7102, the specific HFO spilled in Wabamun Lake, Alberta in August 2005. Through an Effects-Driven Fractionation and Analysis, HFO 7102 was successively fractionated by physical and chemical means. First, a low-temperature vacuum distillation separated the oil into three fractions by volatility. The most toxic of these (lowest median toxic concentration, or LC50), F3, underwent a series of solvent extractions to remove asphaltenes and waxes. The remaining PAH-rich extract (F3-1) was further separated using open column chromatography into non-polar, mid-polar, and polar fractions with groupings approximately by number of aromatic rings. At each stage, fractions and sub-fractions were characterized by GC-MS for compositional analysis and bioassays were conducted with rainbow trout embryos. In this fashion, toxicity thresholds were developed for all fractions and the components of HFO 7102 associated with toxicity were identified and quantified. The F3 fraction was six times more toxic than the whole oil. While the wax fraction (F3-2) was shown to be non-toxic, the remaining PAH-rich extract (F3-1) accounted for all of the toxicity in F3. Future work may be done to determine the relative toxicity of the last fractions generated and identify a range of PAH responsible for fish toxicity. It is expected that the F3-1-2 fraction will be most toxic, as it contains nearly all of the three-ring and most of the four-ring PAH. These size classes of PAH have been associated with chronic toxicity to fish embryos in studies of crude oil. Further separations may be attempted to identify a more specific range of toxic compounds, such as by degree of alkylation. / Thesis (Master, Chemistry) -- Queen's University, 2012-07-31 11:31:15.238
7

O emprego da termogravimetria na determinação da energia de ativação no processo de combustão de óleos combustíveis / Use of thermogravimetric analysis to determine the activation energy in the combustion process of fuels oils

Leiva, Cecilia Rocío Morales 24 August 2005 (has links)
Neste trabalho, determinou-se a energia de ativação (Ea) no processo de combustão de três óleos combustíveis cedidos pela Petrobrás–Cenpes e denominados por A, B e C. Empregou-se análise termogravimétrica (TG) utilizando um sistema Shimadzu 51H e, para todas as amostras observaram-se três regiões oxidativas distintas identificadas como, oxidação à baixa temperatura (LTO), depósito de combustível (FD) e oxidação à alta temperatura (HTO). As energias de ativação foram determinadas como uma função do grau de conversão ('alfa') e temperatura na região LTO e utilizando-se dois métodos cinéticos, denominados ASTM E 1641 (Flynn eWall) e Model Free Kinetics de Vyazovkin. Empregaram-se as seguintes razões de aquecimento: 2,5; 5,0; 10,0; 15,0 e 20,0°C por min entre a temperatura ambiente e 600°C. As demais condições experimentais foram: massa da amostra de aproximadamente 20 mg, suporte de amostra de alumínio e gás de arraste ar sintético com vazão de 100 mL/min. Os valores de Ea encontrados foram os mesmos para ambos os métodos cinéticos: 44 ± 7% kJ/mol ('alfa'=0,1 a 0,9) para amostra A. Para a amostra B os valores de Ea foram em média de 48 ± 4% kJ/mol ('alfa'=0,1 a 0,5) e 66 ± 16% kJ/mol ('alfa'=0,5 a 0,9) e, para a amostra C os valores de Ea foram em média de 58 ± 4% kJ/mol ('alfa'=0,1 a 0,5) e 65 ± 5% kJ/mol ('alfa'=0,5 a 0,9). Conclui-se que a Ea pode ser usada como um parâmetro adequado para apontar uma tendência de comportamento e para caracterizar diferentes óleos sob processo de combustão / In this work activation energies (Ea) in the combustion of three fuels oils were determined through thermogravimetry. The oil samples, here named A, B and C were supplied by Petrobras-Cenpes. The thermogravimetric experiments were performed in a Shimadzu TGA-51H analyzer. In all the combustion experiments three distinct oxidation regions were observed, identified as low temperature oxidation (LTO), fuel deposition (FD) and high temperature oxidation (HTO). Activation energies were determined as a function of conversion degree ('alfa') and temperature for LTO region, following two different procedures, namely Model Free Kinetics and ASTM E 1641. Transient experiments were performed from room temperature up to 600°C, at heating rates of 2.5, 5.0, 10.0, 15.0 and 20.0°C for min. Samples of 20.0 ± 0.5 mg and aluminum crucibles were used. The reacting atmosphere was synthetic air, which was continuously blown over the samples, throughout the analyzer furnace, at a volumetric rate of 100 mL/min. The activation energies resulted equal for both considered methods. For oil A, the activation energy resulted 44 ± 7% kJ/mol ('alfa'=0.1 to 0.9). For oil B it resulted in average 48 ± 4% kJ/mol ('alfa'=0.1 to 0.5) and 66 ± 16% kJ/mol ('alfa'=0.5 to 0.9). For oil C the activation energy resulted 58 ± 3% kJ/mol ('alfa'=0.1 to 0.5) e 65 ± 5% kJ/mol ('alfa'=0.5 to 0.9). It is concluded that the oxidation activation energy is a suitable parameter concerning to point out a tendency of behavior and characterizing different oils under combustion process
8

[pt] DETERMINAÇÃO ELEMENTAR EM ÓLEO LUBRIFICANTE, ÓLEO COMBUSTÍVEL E BIODIESEL POR ICP OES E DRC-ICP-MS / [en] ELEMENTAL DETERMINATION IN LUBRIFICANT OIL AND FUEL OIL BY ICP OES AND DRC-ICP-MS

JEFFERSON RODRIGUES DE SOUZA 13 September 2011 (has links)
[pt] Neste trabalho, são propostas duas metodologias para análise elementar em óleo lubrificante, óleo combustível e biodiesel, através das técnicas de espectrometria de emissão óptica com plasma indutivamente acoplado e espectrometria de massa com plasma indutivamente acoplado com célula de reação dinâmica. Foram combinadas a facilidade e a rapidez na preparação de amostras através da diluição direta em solventes orgânicos, sem tratamento prévio, com a capacidade multielementar das técnicas espectrométricas em estudo. Em ICP OES, foram avaliados os resultados analáticos para os micronebulizadores PFA-100 e Miramist através da análise de dois materiais de referência certificados, a saber, NIST 1634c (óleo combustível) e NIST 1085b (óleo lubrificante). Um planejamento experimental de alta resolução foi realizado para otimização das vazões de Ar e O2 no fluxo de nebulização, com experimentos em duplicata e triplicata no ponto central. Aumentos na razão sinal-ruído foram observados para Ag, Al, B, Ba, Ca, Cr, Cu, Fe, Mn, Si, Ti e V e as maiores razões foram observadas para o micronebulizador PFA-100. As vazões de Ar e O2 foram escolhidas de forma a maximizar essas razões. Para o Miramist, 0,50 L min(-1) (Ar) e 0,020 L min(-1) (O2) foram usados, enquanto para o PFA-100, 0,45 L min(-1) (Ar) e 0,025 L min(-1) (O2). Os materiais de referência NIST 1634c e NIST 1085b foram empregados para validação do método e as melhores recuperações foram obtidas para o micronebulizador PFA-100, com resultados entre 93% e 110%. Os limites de detecção para os dois micronebulizadores não variaram significativamente entre si, estando entre 0,48 ng g(-1) (Mn) e 15,8 ng g(-1) (Al). Em DRC-ICP-MS, foi realizado um planejamento composto central para otimização das condições operacionais do plasma. As vazõoes de argônio de nebulização e auxiliar apresentaram uma influência relevante sobre o teor de Ba++, LaO+ e sobre a intensidade do elemento índio. Uma condição de compromisso foi empregada, sendo 0,42 L min(-1) (Ar de nebulização) e 1,2 L min(-1) (Ar auxiliar). Para redução das interferências espectrais, o metano foi adotado como gás de reação. Os parâmetros operacionais, como a vazão do gás de reação e o parâmetro de rejeição q (Rpq), foram otimizados, visando a menor incidência de interferências sobre isótopos como 52Cr e 56Fe. Os materiais de referência NIST 1634c e NIST 1085b foram empregados para validação do método e as recuperações estiveram entre 90% e 110% para a maioria dos elementos, enquanto os limites de detecção estiveram entre 0,02 ng g(-1) (52Cr) e 7,4 ng g(-1) (40Ca). Os resultados obtidos para o material de referência NIST 1085b foram comparados entre os dois métodos propostos e os mesmos foram considerados concordantes, não diferindo entre eles em mais de 10% para a maioria dos elementos. Os resultados obtidos na análise elementar das amostras de óleo lubrificante mostram que realmente é possível avaliar o desgaste de equipamentos através da metodologia proposta, pois o aumento significativo de alguns elementos, como Fe, foi detectado nas amostras de lubrificante usado, enquanto a análise de amostras de biodiesel mostrou através da técnica de espectrometria de massa, que há nesse biocombustível a presença de elementos que não são contemplados na legislação brasileira. / [en] Two methodologies for elemental analysis of lubrificant oil, fuel oil and biodiesel are proposed, employing inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry with dynamic reaction cell. The methodologies combine the facility and fastness of sample preparation through direct dilution in organic solvents, without any pretreatment, with the multielemental capability of these spectrometric techniques. In ICP OES, the analytical results for the micronebulizers PFA-100 and Miramist were evaluated using two certified reference materials, NIST 1634c (residual fuel oil) and NIST 1085b (wear metals in lubrificant oil). Ar and O2 flow rates were optimized employing a high resolution experimental design was realized, with replicate experiments and triplicate at the central point. Improvement in the signal-to-noise ratio were observed for Ag, Al, B, Ba, Ca, Cr, Cu, Fe, Mn, Si, Ti and V and the highest ratios were obtained with the PFA-100 micronebulizer. The Ar and O2 flow rates were optimized in order to improve these ratios. For Miramist, 0.50 L min(-1) (Ar) e 0.020 L min(-1) (O2) were used and, for PFA-100, 0.45 L min(-1) (Ar) e 0.025 L min(-1) (O2). The reference materials (NIST 1634c and NIST 1085b) were analyzed for validation of the method and the highest recoveries were obtained for the PFA-100 micronebulizer, with results between 93% and 110%. The limits of detection for both micronebulizers were very similar, between a range of 0.48 kg(-1) (Mn) and 15.8 ug kg-1 (Al). In DRC-ICP- MS, a central composite design was realized for the optimization of the plasma operational conditions. The nebulizer and auxiliary flow rates showed a relevant influence on Ba++ and LaO+ content and In intensity. A compromising condition was employed, being 0.42 L min(-1)(Ar nebulizer flow rate), 0.1 L min(-1) (O2 flow rate) and 1.2 L min(-1) (auxiliary flow rate). In order to minimize spectral interference, methane was adopted in this work as reaction gas. The operational conditions of the reaction gas flow rate and rejection parameter q (Rpq), were optimized to minimize the interferences on isotopes, such as 52Cr and 56Fe. Two reference materials (NIST 1634c and NIST 1085b) were employed for method validation and the recoveries were between 90% and 110% for most elements, being the limits of detection between 0.02 ng g(-1) (52Cr) and 7.4 ng g(-1) (40Ca). The results obtained for the reference material NIST 1085b by the two proposed methods were in agreement at a 95% confidence level and did not show difference higher than 10% for most elements. The results obtained by elemental analysis of lubricant oils using the ICP OES methodology showed that it is possible to evaluate equipment wear through the analysis of its oil by the proposed methodology, since a significant increase of some elements concentrations, such as Fe, was detected in used lubricant oil samples. The analysis of biodiesel samples by ICP-MS indicated the presence of elements that are not controlled by the Brazilian legislation.
9

Investigation of the wettability of ammonium nitrate prills /

Kwok, Queenie Sau Man, January 1900 (has links)
Thesis (M. Sc.)--Carleton University, 2001. / Includes bibliographical references (p. 84-90). Also available in electronic format on the Internet.
10

Sintese de carvão ativado e oleo combustivel a partir de borrach de pneu usado / Synthesis of activated carbon and fuel oil from used tyre rubber

Rombaldo, Carla Fabiana Scatolim, 1983- 25 April 2008 (has links)
Orientadores: Antonio Carlos Luz Lisboa, Aparecido dos Reis Coutinho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-11T16:07:51Z (GMT). No. of bitstreams: 1 Rombaldo_CarlaFabianaScatolim_M.pdf: 1092178 bytes, checksum: 2ec2370722d5936a064b2409f70c6bc8 (MD5) Previous issue date: 2008 / Resumo: A recente preocupação com o meio ambiente tornou o pneu usado em um resíduo problemático para a sociedade. Várias são as alternativas para minimizar o número de pneus usados dispostos no meio ambiente, mas ainda não há soluções definitivas. Os pneus usados são difíceis de serem armazenados, ocupando grandes espaços. Para ser possível depositá-los em aterros, os pneus devem ser desintegrados, o que incide em custos e, embora minimize o volume ocupado, não resolve a questão da ocupação do espaço. Por outro lado, quando os pneus usados são descartados desordenadamente, tornam-se locais ideais para proliferação de insetos, diversos vetores de transmissão de doenças, além disso, oferecem risco de incêndio. O presente trabalho teve como objetivo investigar a pirólise para a borracha de pneu usado, visando a obtenção de carvão ativado (CA) a partir da fração sólida da pirólise, e a obtenção de óleo combustível como produtos que apresentam valor agregado. Para o processo de ativação física da fração sólida resultante da pirólise, alguns parâmetros de processo foram investigados, tais como: taxa de aquecimento, temperatura e tempo de ativação, natureza e fluxo do gás ativante. A ativação física do carvão (resíduo sólido da pirólise) apresentou resultados satisfatórios, pois foi obtido CA com área superficial específica de 200 m2.g-1 e rendimento médio de 39%. Para a obtenção do óleo combustível os parâmetros investigados foram: temperatura, taxa de aquecimento e pressão do reator. O óleo combustível obtido a vácuo apresentou poder calorífico de 9704 kcal.kg-1 e teor de enxofre da ordem de 1,40 % (em massa), e somente 0,21 % (vol.) de água, o que o caracteriza como um óleo combustível tipo A (ANP 80/99, de 30/4/1999). Já o óleo obtido em pressão atmosférica pode ser considerado um óleo combustível tipo B (ANP 80/99, de 30/4/1999), pois apresentou teor de enxofre da ordem de 0,93 % (em massa) e poder calorífico de 9824 kcal.kg-1. Todas essas características indicam que a fração líquida da pirólise da borracha de pneu pode ser usada como óleo combustível / Abstract: The current concern with the environment has spawned rising worries about scrap tyres, which have turned an awkward residue. Several alternatives have been proposed to deal with the problem, yet no one has proved to be definitive. Scrap tyres are difficult to be stored, usually demanding large areas. To be dumped in landfills they must first be chopped, which increases cost. When inadequately dumped they offer perfect environments for mosquitoes breeding, which may impose health hazards. The objective of this investigation was to assess the pyrolysis of tyres in order to produce fuel oil (liquid fraction), fuel gas (gas fraction) and a solid residue used as feedstock for activated coal (AC) production. For the physical activation of the solid residue, several operating conditions were investigated: heating rate, activation temperature, activation time, quality and flow of the activating gas. The activation process yield was 39 % and the AC specific surface area was 200 m2.g-1. The pyrolysis process variables investigated were: temperature, heating rate and pressure. The fuel oil obtained under vacuum presents heating value of 9704 kcal kg-1 and sulphur content of 1.40 %, which places it under the category of type A fuel oil , according to ANP 80/99. The fuel oil produced at atmospheric pressure was classified as type B, with heating value of 9824 kcal kg-1 and sulphur content of 0.93 %. The oil characteristics indicate that they can be consumed as fuel oil / Mestrado / Engenharia de Processos / Mestre em Engenharia Química

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