A magnetita, também chamada de ferrita de ferro, é um minério conhecido como imã natural e encontrada em depósitos de ferro. Além desse comportamento intrínseco, a magnetita possui a capacidade de remover os íons metálicos do meio aquoso por fenômenos de adsorção. O seu caráter fortemente magnético a distingue de outros tipos de adsorventes, visto que, é facilmente removida da solução por separação magnética. Neste trabalho estudou-se a adsorção de urânio(VI), na forma de íons UO22+, de solução nítrica pela magnetita sintética. Esta foi preparada por precipitação simultânea adicionando-se uma solução de NaOH à solução contendo os íons Fe2+ e Fe3+. A magnetita sintética, na forma de um pó preto, exibiu uma resposta magnética de atração intensa na presença de um campo magnético, sem contudo tornar-se magnética, um comportamento típico de material superparamagnético constatado por medidas de magnetização. Estudou-se a influência dos parâmetros de adsorção de íons UO22+ tais como o pH, a dose do adsorvente, tempo de contato e a isoterma de equilíbrio. A máxima adsorção de urânio foi encontrada no intervalo de pH entre 4 e 5. Verificou-se que quanto maior a dose de magnetita menor a capacidade de adsorção e maior a remoção de U. Da relação entre adsorção e tempo de contato verificou-se que a remoção aumentou rapidamente com o tempo e atingiu-se a condição de equilíbrio em 30 min. Os resultados da isoterma de equilíbrio apresentaram maior concordância com o modelo de Langmuir, o qual permitiu a determinação da capacidade teórica de saturação da magnetita para o urânio. A interação entre os íons UO22+ e a magnetita foi caracterizada como uma adsorção química e espontânea. / Magnetite, also known as iron ferrite, is a mineral iron and a natural magnet found in iron deposits. In addition to its magnetic intrinsic behavior, the magnetite has the capacity to remove the metallic ions from aqueous medium by adsorption phenomena. The strong magnetic character of magnetite distinguishes it from other adsorbent types, which it allows to be readily removed from solution by magnetic separation. In this work, uranium (VI) adsorption, as UO22+ ions, from nitric solution by synthetic magnetite was investigated. It was prepared by simultaneous precipitation process, adding a NaOH solution into a solution containing Fe2+ and Fe3+ ions. The synthetic magnetite, a black powder, has exhibited a strong magnetic response in presence of a magnetic field, without nevertheless becomes magnetic. This typical superparamagnetic behavior was confirmed by magnetization measurements. Adsorption parameters of UO22+ ions such as pH. the adsorbent dose, contact time and equilibrium isotherm were evaluated. Maximum uranium adsorption was observed in the pH 4.0-5.0 range. It was noticed that increase in magnetite dose increased the percent removal of uranium, but decreased the adsorption capacity of the magnetite. It was observed from the relation between adsorption and contact time that the removal has increased very fast with time, and achieved the equilibrium within 30 minutes. The results of equilibrium isotherm agreed well with the Langmuir model, and so the theorical saturation capacity of the magnetite was determined for uranyl ions. The interaction between UO22+ ions and the magnetite was defined as a spontaneous chemical adsorption.

A magnetita, também chamada de ferrita de ferro, é um minério conhecido como imã natural e encontrada em depósitos de ferro. Além desse comportamento intrínseco, a magnetita possui a capacidade de remover os íons metálicos do meio aquoso por fenômenos de adsorção. O seu caráter fortemente magnético a distingue de outros tipos de adsorventes, visto que, é facilmente removida da solução por separação magnética. Neste trabalho estudou-se a adsorção de urânio(VI), na forma de íons UO22+, de solução nítrica pela magnetita sintética. Esta foi preparada por precipitação simultânea adicionando-se uma solução de NaOH à solução contendo os íons Fe2+ e Fe3+. A magnetita sintética, na forma de um pó preto, exibiu uma resposta magnética de atração intensa na presença de um campo magnético, sem contudo tornar-se magnética, um comportamento típico de material superparamagnético constatado por medidas de magnetização. Estudou-se a influência dos parâmetros de adsorção de íons UO22+ tais como o pH, a dose do adsorvente, tempo de contato e a isoterma de equilíbrio. A máxima adsorção de urânio foi encontrada no intervalo de pH entre 4 e 5. Verificou-se que quanto maior a dose de magnetita menor a capacidade de adsorção e maior a remoção de U. Da relação entre adsorção e tempo de contato verificou-se que a remoção aumentou rapidamente com o tempo e atingiu-se a condição de equilíbrio em 30 min. Os resultados da isoterma de equilíbrio apresentaram maior concordância com o modelo de Langmuir, o qual permitiu a determinação da capacidade teórica de saturação da magnetita para o urânio. A interação entre os íons UO22+ e a magnetita foi caracterizada como uma adsorção química e espontânea. / Magnetite, also known as iron ferrite, is a mineral iron and a natural magnet found in iron deposits. In addition to its magnetic intrinsic behavior, the magnetite has the capacity to remove the metallic ions from aqueous medium by adsorption phenomena. The strong magnetic character of magnetite distinguishes it from other adsorbent types, which it allows to be readily removed from solution by magnetic separation. In this work, uranium (VI) adsorption, as UO22+ ions, from nitric solution by synthetic magnetite was investigated. It was prepared by simultaneous precipitation process, adding a NaOH solution into a solution containing Fe2+ and Fe3+ ions. The synthetic magnetite, a black powder, has exhibited a strong magnetic response in presence of a magnetic field, without nevertheless becomes magnetic. This typical superparamagnetic behavior was confirmed by magnetization measurements. Adsorption parameters of UO22+ ions such as pH. the adsorbent dose, contact time and equilibrium isotherm were evaluated. Maximum uranium adsorption was observed in the pH 4.0-5.0 range. It was noticed that increase in magnetite dose increased the percent removal of uranium, but decreased the adsorption capacity of the magnetite. It was observed from the relation between adsorption and contact time that the removal has increased very fast with time, and achieved the equilibrium within 30 minutes. The results of equilibrium isotherm agreed well with the Langmuir model, and so the theorical saturation capacity of the magnetite was determined for uranyl ions. The interaction between UO22+ ions and the magnetite was defined as a spontaneous chemical adsorption.

Thesis (M.Phil. (Environmental Law and Management)) --University of Limpopo, 2009 / In this study hazardous waste is defined as well as its classes.The current status of hazardous waste management, available legislation,enforcement and minimum requirements are discussed.Hazardous waste chemicals produced at University of Limpopo (Turfloop Campus),their amounts and their management were determined.They are compared to minimum requirements from Department of Water Affairs and Forestry.Other Universities hazardous waste management programmes were looked at.

Graduation date: 1994

Thesis (LL. M.)--Dalhousie University, 1990. / Includes bibliographical references (leaves 245-260).

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

Waste from healthcare facilities or similar facilities includes components of various physical, chemical and biological character that require special approaches during the handling, specifically with regard to possible risks to human health and the environment. Nowadays a challenge for waste management system becomes waste produced in healthcare facilities and contributes too many reasons, such as population growth and rising life expectancy. The rate of waste production from healthcare facilities depends on the facility type, its specialty, inpatient capacity, level of amenities and location. Waste from healthcare facilities need to be sorted and removed to avoid endangering the health of patients, healthcare workers and the environment. The aim of the study was to describe and compare the waste management systems in healthcare facilities between Czech Republic and Kazakhstan. Within the work was performed statistical analysis of the healthcare waste generation in the selected region of Kazakhstan. The results show that the only factor that affects the rate of waste generation is inpatient capacity of healthcare facility. It was also found that the production of healthcare waste differs significantly between ambulatory and stationary care facilities. The research results show that public...

Orientadores: Egle Novaes Teixeira, Ennio Peres da Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-04T01:53:03Z (GMT). No. of bitstreams: 1 Batista_TerezaRosanaOrrico_M.pdf: 13280471 bytes, checksum: b1b99c28a7618d0aa975c970129b663f (MD5) Previous issue date: 2004 / Resumo: Neste trabalho teve-se como objetivo propor uma metodologia para avaliação da energia associada ao resíduo sólido industrial (RSI) e sua aplicação à Região Metropolitana de Campinas (RMC). A metodologia foi baseada numa revisão bibliográfica, sobre aspectos ambientais e energéticos relacionados ao resíduo sólido industrial. No roteiro metodológico propõe-se caracterizar a área de estudo; a produção e gestão do RSI; a classificação energética e o estudo quali-quantitativo da energia associada ao RSI; e, avaliação da aplicabilidade dos mecanismos de aproveitamento energético propostos para a região. A aplicação da metodologia à RMC mostrou-se válida e resultou numa apresentação sintética da realidade sócio-ambienta!, do setor industrial e da destinação de resíduo, bem como indicou as potencialidades quanto ao aproveitamento energético de RSI, na região. Com os resultados obtidos constata-se a importância da questão da produção e destinação de RSI, na RMC, e o significado, em termos de potência elétrica, para os valores da energia associada ao resíduo com fator de conversão energética conhecido, presente na amostra estudada / Abstract: The aim of tbis work is to propose a methodology to evaluate the energy associated to the industrial solid wastes and its application in the Metropolitan Region of Campinas. The methodology was based on a bibliograpbical revision about environmental and energetic aspects related to the industrial solid wastes. The methodological route proposes: the characterization of the research area and the production/management of the industrial solid wastes; the energetic classification and the qualitative/quantitative research of the energy associated to the industrial solid wastes; and, the valuation of the applicability of the mechanisms of energetic utilization proposed to the region. The application of the methodology in the Metropolitan Region of Campinas proved to be valid and it resulted in a synthetica1 presentation of the social and environmental reality of the industrial sector and the destination of the wastes, as well as it indicated the potentialities related to the energetic utilization of the industrial solid wastes in the region. The obtained results show the importance of the matter of the production and the destination of the industrial solid wastes in the Metropolitan Region of Campinas, and the meaning, in terms of electric potency, of the values of the energy associated to the wastes with a known factor of energetic conversion shown in the researched sample / Mestrado / Planejamento de Sistemas Energeticos / Mestre em Planejamento de Sistemas Energéticos

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management