Este trabalho avalia por meio de um IEV - Inventário de Emissão Veicular, a contribuição dos veículos automotores na poluição do ar, nos municípios de Sorocaba e Votorantim, dando ênfase às suas características de frota e posição geográfica, seus impactos, quantificação e qualificação de emissão de poluentes, através de experimentos com a utilização de diesel metropolitano - B2 e biodiesel - B100 (soja), como combustível nos veículos equipados com motores de ignição por compressão (motor diesel), em substituição total ou parcial ao diesel existente no mercado nacional e a utilização de gasolina padrão da Petrobrás e de AEHC - ácool etílico hidratado combustível em veículos flex equipados com motores de ignição por centelha (motor ciclo Otto), sem os conversores catalíticos, buscando identificar as condições mais próximas da realidade da manutenção da frota. Para este trabalho, considera-se que os poluentes de interesse são o monóxido de carbono (\'C\'O\'), os hidrocarbonetos (\'H\'C\'), os óxidos de nitrogênio (\'N\'O IND.X\'), dióxido de carbono (\'C\'O IND.2\'), hidrocarbonetos sem metano (\'N\'M\'H\'C\'), aldeídos, formaldeídos e acetaldeídos. A análise dos dados obtidos nos experimentos, sem a utilização de conversor catalítico, utilizando gasolina padrão e AEHC - álcool etílico hidratado combustível, com relação aos limites L-4 do Proconve, demonstrou que os fatores de emissão (FE) obtidos, com gasolina padrão, resultaram em aumento em torno de 184% para \'C\'O\', 167% para \'H\'C\', 680% para \'N\'O IND.X\', 468% para \'N\'M\'H\'C\' e 23% para aldeídos, já para os FE obtidos com AEHC - álcool etílico hidratado combustível, resultaram em aumento em torno de 150% para \'C\'O\', 138% para \'H\'C\', 330% para \'N\'O IND.X\', 434% para \'N\'M\'H\'C\' e 405% para aldeídos. A simulação das emissões da frota real de modelos ciclo Otto e diesel em estudo sem a utilização de conversores catalíticos, ou seja, para 317.539 veículos, sendo 75.294 movidos à AEHC - álcool etílico hidratado combustível, 157.694 movidos à gasolina padrão, 16.042 movidos à biodiesel metropolitano B2, 64.730 tipo motocicletas movidas à gasolina, excluindo-se 3.779 veículos diversos entre reboques e semi-reboques, foi constatado que, as emissões totais seriam de 21.628,525 t/ano de \'C\'O\', 3.011,947 t/ano de \'H\'C\', 5.321,934 t/ano de \'N\'O IND.X\', 540.500,022 t/ano de \'C\'O IND.2\', 2.660,792 t/ano de \'N\'M\'H\'C\', 89,253 t/ano de formaldeídos, 138,565 t/ano de acetaldeídos e 227,818 t/ano de aldeídos. A simulação das emissões da frota real de modelos ciclo Otto e diesel em estudo sem a utilização de conversores catalíticos, ou seja, para 317.539 veículos, sendo 75.294 movidos à AEHC - álcool etílico hidratado combustível, 157.694 movidos à gasolina padrão, 16.042 movidos à biodiesel B100, 64.730 tipo motocicletas movidas à gasolina, excluindo-se 3.779 veículos diversos entre reboques e semi-reboques, foi constatado que, as emissões totais seriam de 21.628,425 t/ano de \'C\'O\', 3.011,947 t/ano de \'H\'C\', 5.302,977 t/ano de \'N\'O IND.X\', 540.875,538 t/ano de \'C\'O IND.2\', 2.660,792 t/ano de \'N\'M\'H\'C\', 91,039 t/ano de formaldeídos, 138,828 t/ano de acetaldeídos e 229,868 t/ano de aldeídos. Os resultados obtidos durante os experimentos, demonstram que uma manutenção inadequada, torna ineficaz qualquer ganho ambiental obtido, tendo em vista a crescente ampliação da frota existente, baseada em políticas públicas equivocadas, as quais, continuam a incentivar a aquisição de veículos particulares em detrimento do sistema de transporte público, o qual continua ineficiente, além de caro para os padrões econômicos da população. / This study evaluates by means of a IEV - inventory of vehicle emission to propagate, the contribution of motor vehicles in air pollution in the cities of Sorocaba and Votorantim, of the emphasis to the characteristics of the fleet and the geographic position of these cities, to the impacts of these characteristics, the quantification and qualification of the emission of pollutants, through experiments with the use of diesel metropolitano - B2 and biodiesel - B100, as combustible in vehicles equipped with engines of ignition for compression (motor diesel), in total or partial substitution to existing diesel in national market, and gasoline standard of Petrobras and AEHC - combustible hidrated ethyl alcohol and its mixtures in equipped vehicles flex with engines of ignition for flash (cycle Otto motor), without the catalytic converters; searching to identify the conditions next to the reality of the maintenance of the fleet. For this work, it is considered that the interest pollutants are the carbono monoxide (\'C\'O\'), hidrocarbons (\'H\'C\'), the nitrogen oxides (\'N\'O IND.X\'), carbono dioxide (\'C\'O IND.2\'), non-methane hydrocarbons (\'N\'M\'H\'C\'), aldehydes, formaldehydes and acetaldehydes. The analysis of the data gotten in the experiments, without the use of catalytic converter, using gasoline standard and AEHC - hydrated ethilic alcohol, with regard to the L-4 limits of the Proconve, demonstrated that the factors of emission (FE) gotten, with gasoline standard, had resulted in increase around 184% for \'C\'O\', 167% for \'H\'C\', 680% for \'N\'O IND.X\', 468% for \'N\'M\'H\'C\' and 23% for aldehydes, already for the FE gotten with AEHC, had resulted in increase around 150% for \'C\'O\', 138% for \'H\'C\', 330% for \'N\'O IND.X\', 434% for \'N\'M\'H\'C\' and 405% for aldehydes. The simulation of the emissions of the real fleet of models cycle Otto and diesel in study without the use of catalytic converters, that is, for 317.539 vehicles, being 75.924 moved to the AEHC, 157.694 moved by gasoline, 16.042 moved by the metropolitan biodiesel B2, 64.730 type motorcycles moved by the gasoline, abstaining itself 3.779 diverse vehicles between tows and semitrailers, was evidenced that, the total emissions would be of 21.628,525 tons per year (tpy) of \'C\'O\', 3.011,947 tpy of \'H\'C\', 5.231,934 tpy of \'N\'O IND.X\', 540.500,022 tpy of \'C\'O IND.2\', 2.660,792 tpy of \'N\'M\'H\'C\', 89,253 tpy of formaldehyde, 138,565 tpy for acetaldehyde and 227,818 tpy for aldehyde. The simulation of the emissions of the real fleet of models cycle Otto and diesel in study without the use of catalytic converters, that is, for 317.539 vehicles, being 75.294 moved by the AEHC, 157.694 moved by gasoline, 16.042 moved by the biodiesel B100 from syo bean oil, 64.730 type motorcycles moved by the gasoline, abstaining itself 3.779 diverse vehicles between tows and semitrailers, was evidenced that, the total emissions would be of 21.628,425 tpy of \'C\'O\', 3.011,947 tpy of \'H\'C\', 5.302,977 tpy of \'N\'O IND.X\', 540.875,538 tpy of \'C\'O IND.2\', 2.660,792 tpy of \'N\'M\'H\'C\', 91,039 tpy of formaldehyde, 138,828 tpy for acetaldeíhyde and 229,868 tpy for aldehydes. The results obtained during the experiments show that inadequate maintenance, makes ineffective any environmental gains achieved, with a view to increasing expansion of the existing fleet, based on misguided public policies, which continue to encourage the purchase of cars at the expense of public transport system, which remains inefficient, and expensive for the economic standards of the population.

Este trabalho teve o objetivo de verificar a existência de correlação entre as concentrações de amônia no município de São Paulo e as concentrações dos poluentes regulamentados associados à emissão veicular. Foi testada a correlação estatística entre as concentrações de amônia e os seguintes parâmetros: fumaça, partículas inaláveis finas, monóxido de carbono, dióxido, monóxido e óxidos de nitrogênio; temperatura e umidade relativa do ar. Os dados utilizados foram fornecidos pela CETESB e medidos na Estação Pinheiros no período de abril/12 a setembro/13. Os resultados obtidos nas análises foram que as concentrações diárias de amônia variaram de 1,3 g/m³ (limite de detecção do método) a 40,0 g/m³, sendo que a média aritmética das concentrações desse período foi de 14,3 g/m³ ± 9,5 g/m³ e a mediana de 14,1 g/m³. Esse valor de média é muito próximo às encontradas em Santiago, Roma, Cidade do México, Pequim e Xian, e os maiores valores diários de amônia foram observados entre novembro/2012 e fevereiro/2013 e as concentrações médias por dia da semana apontaram uma variação entre 12,1 g/m³ a 19,0 g/m³, sendo que a maior média foi observada no domingo. Na comparação com os poluentes atmosféricos, foram observadas algumas tendências de comportamento semelhantes em determinados períodos, porém as correlações foram muito fracas. Com relação aos parâmetros meteorológicos, observou-se que quando ocorreu a máxima de temperatura, o valor de concentração de amônia também foi elevado, porém nos dias em que as concentrações de amônia foram mais altas, as máximas de temperatura não foram as mais elevadas. A correlação encontrada entre a amônia e temperatura foi muito fraca e nos dias com os maiores percentuais de umidade relativa do ar apresentaram valores baixos de concentração de amônia. Não foi possível identificar correlação significante entre concentrações de amônia em relação aos demais poluentes atmosféricos de influência veicular e aos parâmetros meteorológicos temperatura e umidade relativa do ar. Portanto, para o período estudado, as emissões veiculares não influenciaram as concentrações de amônia presentes na região de estudo. Assim, sugere-se o prosseguimento do monitoramento de amônia no ar e estudos posteriores, tendo em vista o aumento de veículos com catalisadores veiculares que podem ocasionar emissão de amônia. / The general objective of this study was to verify the existence of correlation between the ammonia concentrations in São Paulo city and the concentrations of regulated pollutants associated with vehicle emissions. The concentration of air pollutants: black smoke, fine particulate matter, carbon monoxide and nitrogen dioxide, monoxide and oxides; temperature and relative humidity were statistically tested. CETESB measured the pollutants data at Pinheiros Station from April/12 to September/13. The daily ammonia concentrations ranged from 1.3 g/m³ (method detection limit) to 40.0 g/m³ and the average concentrations of this period was 14.3 g/m³ ± 9.5 g/m³ and the median 14.1 g/m³. This average value is very close to those found in Santiago, Rome, Mexico City, Beijing and Xi\'an, the largest daily ammonia values were observed between November/2012 and February/2013, and the average concentrations by day of week pointed a variation between 12.1 to 19.0 g/m³. The highest average was observed on Sunday. In the comparison between the atmospheric pollutants and air temperature and humidity some similar trends behavior were observed in certain periods, but the correlations were very weak. It was not possible to identify a significant correlation between ammonia concentration with air pollutants vehicular influence and meteorological parameters temperature and relative humidity. Therefore, for the period studied, vehicle emissions did not affect the concentrations of ammonia present in the study area. It is suggested to continue the monitoring of ammonia in the air and further studies due to the increase of vehicles equipped with catalysts, which can cause emission of ammonia.

In this work, slurries of powder catalysts are washcoated on 22 mm diameter and 13 mm height cordierite monoliths. CeO2-ZrO2 (CZO) and CeO2-ZrO2- Al2O3 (CZAO) mixed oxides are synthesized by co-precipitation and sol-gel methods respectively, to be used as support materials of Pd and Rh metals. Metal loaded CZO is mixed with gamma phase alumina. Powder catalysts and their slurries are characterized by XRD, BET, ICP-MS and the monolithic catalysts are imaged by SEM. Catalytic activities of monolithic catalysts are tested in dynamic test system which is computerized and basically composed of gas flow control and conditioning units, split furnace, quartz reactor, mass spectrometer and CO analyzer. Gas mixture containing CO, C3H6, C3H8, NO, H2, O2, CO2, SO2, H2O and N2 is used to simulate the exhaust gas of gasoline vehicles. O2 is oscillated at 1 Hz frequency around the stoichiometric condition. Monolithic catalyst in the reactor is heated and cooled between 150 &ordm / C and 600 &ordm / C. Gas composition data from massspectrometer and CO analyzer and temperature data from thermocouple at the monolith entrance, are converted to conversion versus temperature graphs. Results of 26 activity tests are compared. Catalyst containing coimpregnated CZO support material with metals, showed the lowest loss of catalytic performance after exposure to SO2 during activity tests. Catalyst containing separately impregnated CZO support material, showed the highest resistance against thermal aging at 900 &ordm / C and 1000 &ordm / C, and even improved catalytic activity after aging. These catalysts showed higher resistances against the applied procedures than the commercial catalyst.

No description available.

Este trabalho teve o objetivo de verificar a existência de correlação entre as concentrações de amônia no município de São Paulo e as concentrações dos poluentes regulamentados associados à emissão veicular. Foi testada a correlação estatística entre as concentrações de amônia e os seguintes parâmetros: fumaça, partículas inaláveis finas, monóxido de carbono, dióxido, monóxido e óxidos de nitrogênio; temperatura e umidade relativa do ar. Os dados utilizados foram fornecidos pela CETESB e medidos na Estação Pinheiros no período de abril/12 a setembro/13. Os resultados obtidos nas análises foram que as concentrações diárias de amônia variaram de 1,3 g/m³ (limite de detecção do método) a 40,0 g/m³, sendo que a média aritmética das concentrações desse período foi de 14,3 g/m³ ± 9,5 g/m³ e a mediana de 14,1 g/m³. Esse valor de média é muito próximo às encontradas em Santiago, Roma, Cidade do México, Pequim e Xian, e os maiores valores diários de amônia foram observados entre novembro/2012 e fevereiro/2013 e as concentrações médias por dia da semana apontaram uma variação entre 12,1 g/m³ a 19,0 g/m³, sendo que a maior média foi observada no domingo. Na comparação com os poluentes atmosféricos, foram observadas algumas tendências de comportamento semelhantes em determinados períodos, porém as correlações foram muito fracas. Com relação aos parâmetros meteorológicos, observou-se que quando ocorreu a máxima de temperatura, o valor de concentração de amônia também foi elevado, porém nos dias em que as concentrações de amônia foram mais altas, as máximas de temperatura não foram as mais elevadas. A correlação encontrada entre a amônia e temperatura foi muito fraca e nos dias com os maiores percentuais de umidade relativa do ar apresentaram valores baixos de concentração de amônia. Não foi possível identificar correlação significante entre concentrações de amônia em relação aos demais poluentes atmosféricos de influência veicular e aos parâmetros meteorológicos temperatura e umidade relativa do ar. Portanto, para o período estudado, as emissões veiculares não influenciaram as concentrações de amônia presentes na região de estudo. Assim, sugere-se o prosseguimento do monitoramento de amônia no ar e estudos posteriores, tendo em vista o aumento de veículos com catalisadores veiculares que podem ocasionar emissão de amônia. / The general objective of this study was to verify the existence of correlation between the ammonia concentrations in São Paulo city and the concentrations of regulated pollutants associated with vehicle emissions. The concentration of air pollutants: black smoke, fine particulate matter, carbon monoxide and nitrogen dioxide, monoxide and oxides; temperature and relative humidity were statistically tested. CETESB measured the pollutants data at Pinheiros Station from April/12 to September/13. The daily ammonia concentrations ranged from 1.3 g/m³ (method detection limit) to 40.0 g/m³ and the average concentrations of this period was 14.3 g/m³ ± 9.5 g/m³ and the median 14.1 g/m³. This average value is very close to those found in Santiago, Rome, Mexico City, Beijing and Xi\'an, the largest daily ammonia values were observed between November/2012 and February/2013, and the average concentrations by day of week pointed a variation between 12.1 to 19.0 g/m³. The highest average was observed on Sunday. In the comparison between the atmospheric pollutants and air temperature and humidity some similar trends behavior were observed in certain periods, but the correlations were very weak. It was not possible to identify a significant correlation between ammonia concentration with air pollutants vehicular influence and meteorological parameters temperature and relative humidity. Therefore, for the period studied, vehicle emissions did not affect the concentrations of ammonia present in the study area. It is suggested to continue the monitoring of ammonia in the air and further studies due to the increase of vehicles equipped with catalysts, which can cause emission of ammonia.

Este trabalho avalia por meio de um IEV - Inventário de Emissão Veicular, a contribuição dos veículos automotores na poluição do ar, nos municípios de Sorocaba e Votorantim, dando ênfase às suas características de frota e posição geográfica, seus impactos, quantificação e qualificação de emissão de poluentes, através de experimentos com a utilização de diesel metropolitano - B2 e biodiesel - B100 (soja), como combustível nos veículos equipados com motores de ignição por compressão (motor diesel), em substituição total ou parcial ao diesel existente no mercado nacional e a utilização de gasolina padrão da Petrobrás e de AEHC - ácool etílico hidratado combustível em veículos flex equipados com motores de ignição por centelha (motor ciclo Otto), sem os conversores catalíticos, buscando identificar as condições mais próximas da realidade da manutenção da frota. Para este trabalho, considera-se que os poluentes de interesse são o monóxido de carbono (\'C\'O\'), os hidrocarbonetos (\'H\'C\'), os óxidos de nitrogênio (\'N\'O IND.X\'), dióxido de carbono (\'C\'O IND.2\'), hidrocarbonetos sem metano (\'N\'M\'H\'C\'), aldeídos, formaldeídos e acetaldeídos. A análise dos dados obtidos nos experimentos, sem a utilização de conversor catalítico, utilizando gasolina padrão e AEHC - álcool etílico hidratado combustível, com relação aos limites L-4 do Proconve, demonstrou que os fatores de emissão (FE) obtidos, com gasolina padrão, resultaram em aumento em torno de 184% para \'C\'O\', 167% para \'H\'C\', 680% para \'N\'O IND.X\', 468% para \'N\'M\'H\'C\' e 23% para aldeídos, já para os FE obtidos com AEHC - álcool etílico hidratado combustível, resultaram em aumento em torno de 150% para \'C\'O\', 138% para \'H\'C\', 330% para \'N\'O IND.X\', 434% para \'N\'M\'H\'C\' e 405% para aldeídos. A simulação das emissões da frota real de modelos ciclo Otto e diesel em estudo sem a utilização de conversores catalíticos, ou seja, para 317.539 veículos, sendo 75.294 movidos à AEHC - álcool etílico hidratado combustível, 157.694 movidos à gasolina padrão, 16.042 movidos à biodiesel metropolitano B2, 64.730 tipo motocicletas movidas à gasolina, excluindo-se 3.779 veículos diversos entre reboques e semi-reboques, foi constatado que, as emissões totais seriam de 21.628,525 t/ano de \'C\'O\', 3.011,947 t/ano de \'H\'C\', 5.321,934 t/ano de \'N\'O IND.X\', 540.500,022 t/ano de \'C\'O IND.2\', 2.660,792 t/ano de \'N\'M\'H\'C\', 89,253 t/ano de formaldeídos, 138,565 t/ano de acetaldeídos e 227,818 t/ano de aldeídos. A simulação das emissões da frota real de modelos ciclo Otto e diesel em estudo sem a utilização de conversores catalíticos, ou seja, para 317.539 veículos, sendo 75.294 movidos à AEHC - álcool etílico hidratado combustível, 157.694 movidos à gasolina padrão, 16.042 movidos à biodiesel B100, 64.730 tipo motocicletas movidas à gasolina, excluindo-se 3.779 veículos diversos entre reboques e semi-reboques, foi constatado que, as emissões totais seriam de 21.628,425 t/ano de \'C\'O\', 3.011,947 t/ano de \'H\'C\', 5.302,977 t/ano de \'N\'O IND.X\', 540.875,538 t/ano de \'C\'O IND.2\', 2.660,792 t/ano de \'N\'M\'H\'C\', 91,039 t/ano de formaldeídos, 138,828 t/ano de acetaldeídos e 229,868 t/ano de aldeídos. Os resultados obtidos durante os experimentos, demonstram que uma manutenção inadequada, torna ineficaz qualquer ganho ambiental obtido, tendo em vista a crescente ampliação da frota existente, baseada em políticas públicas equivocadas, as quais, continuam a incentivar a aquisição de veículos particulares em detrimento do sistema de transporte público, o qual continua ineficiente, além de caro para os padrões econômicos da população. / This study evaluates by means of a IEV - inventory of vehicle emission to propagate, the contribution of motor vehicles in air pollution in the cities of Sorocaba and Votorantim, of the emphasis to the characteristics of the fleet and the geographic position of these cities, to the impacts of these characteristics, the quantification and qualification of the emission of pollutants, through experiments with the use of diesel metropolitano - B2 and biodiesel - B100, as combustible in vehicles equipped with engines of ignition for compression (motor diesel), in total or partial substitution to existing diesel in national market, and gasoline standard of Petrobras and AEHC - combustible hidrated ethyl alcohol and its mixtures in equipped vehicles flex with engines of ignition for flash (cycle Otto motor), without the catalytic converters; searching to identify the conditions next to the reality of the maintenance of the fleet. For this work, it is considered that the interest pollutants are the carbono monoxide (\'C\'O\'), hidrocarbons (\'H\'C\'), the nitrogen oxides (\'N\'O IND.X\'), carbono dioxide (\'C\'O IND.2\'), non-methane hydrocarbons (\'N\'M\'H\'C\'), aldehydes, formaldehydes and acetaldehydes. The analysis of the data gotten in the experiments, without the use of catalytic converter, using gasoline standard and AEHC - hydrated ethilic alcohol, with regard to the L-4 limits of the Proconve, demonstrated that the factors of emission (FE) gotten, with gasoline standard, had resulted in increase around 184% for \'C\'O\', 167% for \'H\'C\', 680% for \'N\'O IND.X\', 468% for \'N\'M\'H\'C\' and 23% for aldehydes, already for the FE gotten with AEHC, had resulted in increase around 150% for \'C\'O\', 138% for \'H\'C\', 330% for \'N\'O IND.X\', 434% for \'N\'M\'H\'C\' and 405% for aldehydes. The simulation of the emissions of the real fleet of models cycle Otto and diesel in study without the use of catalytic converters, that is, for 317.539 vehicles, being 75.924 moved to the AEHC, 157.694 moved by gasoline, 16.042 moved by the metropolitan biodiesel B2, 64.730 type motorcycles moved by the gasoline, abstaining itself 3.779 diverse vehicles between tows and semitrailers, was evidenced that, the total emissions would be of 21.628,525 tons per year (tpy) of \'C\'O\', 3.011,947 tpy of \'H\'C\', 5.231,934 tpy of \'N\'O IND.X\', 540.500,022 tpy of \'C\'O IND.2\', 2.660,792 tpy of \'N\'M\'H\'C\', 89,253 tpy of formaldehyde, 138,565 tpy for acetaldehyde and 227,818 tpy for aldehyde. The simulation of the emissions of the real fleet of models cycle Otto and diesel in study without the use of catalytic converters, that is, for 317.539 vehicles, being 75.294 moved by the AEHC, 157.694 moved by gasoline, 16.042 moved by the biodiesel B100 from syo bean oil, 64.730 type motorcycles moved by the gasoline, abstaining itself 3.779 diverse vehicles between tows and semitrailers, was evidenced that, the total emissions would be of 21.628,425 tpy of \'C\'O\', 3.011,947 tpy of \'H\'C\', 5.302,977 tpy of \'N\'O IND.X\', 540.875,538 tpy of \'C\'O IND.2\', 2.660,792 tpy of \'N\'M\'H\'C\', 91,039 tpy of formaldehyde, 138,828 tpy for acetaldeíhyde and 229,868 tpy for aldehydes. The results obtained during the experiments show that inadequate maintenance, makes ineffective any environmental gains achieved, with a view to increasing expansion of the existing fleet, based on misguided public policies, which continue to encourage the purchase of cars at the expense of public transport system, which remains inefficient, and expensive for the economic standards of the population.

Tato diplomová práce se zabývá turbodmychadly a CFD simulací turbodmychadla s integrovaným přepouštěcím ventilem pro benzínový motor. Cílem je poskytnout všeobecný přehled o přeplnování a konstrukci turbodmychadel. Práce popisuje proces tvorby 3-rozměrného virtuálního modelu sestavy turbínové skříně, extrakci negativního objemu plynů, tvorbu meshe a nastavení počítačové CFD simulace, která je v závěru práce vyhodnocena. Výsledky simulace slouží pro návrh odlišného provedení turbínové skříně za účelem zlepšení rozložení teplot výfukových plynů na výstupu a zkrácení aktivační doby výfukového katalyzátoru.

Includes abstract. / Includes bibliographical references (leaves 74-79). / Historically the platinum group metals (PGMs) have been, and are still being dissolved by means of rather aggressive methods, e.g. aqua regia. Limited research has been conducted into the dissolution of the PGMs using different oxidizing agents. The dissolution of gold on the other hand has been afforded extensive research, and numerous papers and review articles have been published on the subject. The last number of years has seen the biggest application by volume of the PGMs as part of autocatalysts towards the degradation of harmful motor vehicle exhaust gases. This has subsequently sparked research into the recovery of specifically platinum, palladium, and rhodium from spent autocatalysts. Currently pyrometallurgical recovery of PGMs is being employed predominantly. A hydrometallurgical process on the other hand is, based on current technology, still a rather aggressive process that makes for high maintenance costs and an unpleasant environment. Gold has traditionally been dissolved by making use of cyanide, which is still the major route for gold dissolution. Due to environmental concerns lixiviants such as thiosulphate (S2O3 2-), thiourea (H2NCSNH2), and thiocyanate (SCN-) are gaining acceptance due to them being more environmentally friendly and giving good recoveries. These ‘softer’ alternatives have however not been tested on the PGMs. It is therefore the aim of this study to obtain an improved understanding of the leaching of the PGMs using lixiviants less aggressive than aqua-regia. These lixiviants include (i) SCN-, (ii) S2O3 2-, (iii) H2NCSNH2, and (iv) AlCl3/HCl. A thermodynamic study highlighted the fact that thermodynamic data for platinum-, palladium- and rhodium complexes are basically non-existent. To therefore obtain a clearer thermodynamic understanding of the leaching of the platinum group metals by means of these alternative lixiviants, future detailed speciation and thermodynamic investigations need to be conducted. An exploratory electrochemical investigation focusing on open circuit potentials and potentiodynamic scans, showed AlCl3 / HCl / NaOCl to be a good candidate for the leaching of the platinum group metals followed by SCN- / Fe3+ and CS(NH2)2 / Fe3+. Actual leach results, employing virgin autocatalysts as sample material, again highlighted the potential of AlCl3 / HCl / NaOCl as being a good lixiviant system. The surprise package, however, has been SCN- / Fe3+ that rendered very good results for Pd and Pt.

The objective of this study was to evaluate the practical limits of EPA's NONROAD 2005 to accurately simulate Central Florida conditions, especially with regard to lawn and garden equipment. In particular we investigated a NONROAD emission inventory using default inputs and then created a locally specific emission inventory. These emission inventories were prepared for Orange, Osceola, and Seminole county and focused only on the VOC and NOx emissions caused by lawn and garden equipment. The model was manipulated to assess its ability to represent this specific category of nonroad equipment for a given airshed first by running a base case scenario using default data and then by developing a locally-specific scenario through administration of a survey. The primary purpose of the survey was to evaluate local values for equipment population, equipment characteristics, activity estimates, and other relevant information. To develop these local input estimates, data were collected concerning population and usage statistics in the Central Florida area and were combined with emission factors, load factors, allocation factors, and other needed values that have been previously established by the U.S. EPA. The results of the NONROAD model were compared with the resulting emission estimates calculated from locally derived inputs, and as a result of the analysis an accurate emission estimate was calculated. In addition, several possible air quality action steps were further assessed according to feasibility, cost, and predicted emission benefit. These potential management projects were further investigated by assessing the success of other similar projects in other cities in an effort to establish specific costs and emission benefits as they relate to the tri-county area.

Cerium and zirconium oxides are important materials in industrial catalysis. Particularly, the great advances attained in the past 30 years in controlling levels of gaseous pollutants released from internal combustion engines can be attributed to the development of catalysts employing these materials. Unfortunately, oxides of sulfur are known threats to the longevity of many catalytic systems by irreversibly interacting with catalytic materials over some time period. In this work, polycrystalline cerium-zirconium mixed-metal-oxide (MMO) solid solutions of various molar ratios were synthesized. High resolution x-ray photoelectron spectroscopy (XPS) was used to characterize the model system. The spectral data was examined for revelation of the surface species that form on these metal oxides after insitu exposures to sulfur dioxide at various temperatures. The model catalysts were exposed to sulfur dioxide using a custom modified in-situ reaction cell. A reliable sample platen heater was designed and built to allow the exposure of the model system at temperatures up to 673 K. The results of this study demonstrate the formation of sulfate and sulfite adsorbed sulfur species. Temperature and compositional dependencies were displayed, with higher temperatures and ceria molar ratios displaying a larger propensity for forming surface sulfur species. In addition to analysis of sulfur photoemission, the photoemission regions of oxygen, zirconium, and cerium were examined for the materials used in this study before and after the aforementioned treatments with sulfur dioxide. The presence of surface hydroxyl groups was observed and metal oxidation state changes were probed to further enhance the understanding of sulfur dioxide adsorption on the synthesized materials. Palladium loaded mixed-metal oxides were synthesized using a unique solid-state methodology to probe the effect of palladium addition on sulfur dioxide adsorption. Microscopic characterization of the wafers made using palladium-loaded MMO materials provide justification for using this material preparation method in surface science studies. The addition of palladium to this model system is shown to have a strong effect on the magnitude of adsorption for sulfur dioxide on some material/exposure condition combinations. Ceria/zirconia sulfite and sulfate species are identified on the palladium-loaded MMO materials with adsorption sites located on the exposed oxide sites.