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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

Utiliza??o de res?duos eletr?nicos no Instituto Federal do Amap?: Uma proposta de arte e educa??o / Use of electronic waste in the Federal Institute of Education of Amapa: A proposal of art and education

BURASLAN, Marcus Vinicius da Silva 16 January 2017 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-03-23T18:55:13Z No. of bitstreams: 1 2017 - Marcus Vinicius da Silva Buraslan.pdf: 2691930 bytes, checksum: ae2883ca17abc595becc4b32d48ece12 (MD5) / Made available in DSpace on 2018-03-23T18:55:13Z (GMT). No. of bitstreams: 1 2017 - Marcus Vinicius da Silva Buraslan.pdf: 2691930 bytes, checksum: ae2883ca17abc595becc4b32d48ece12 (MD5) Previous issue date: 2017-01-16 / The production of electronic waste presents itself as a major challenge by public, municipal, state and federal agencies of Brazil. The federal institutes are included in this scenario and should seek ways of collaborating in the reduction of production of this waste and find ways to make good use of them. In this sense, the environmental education allied with the artistic education can contribute in the reutilization of computer waste in the Institutes. The purpose of this research was to develop experiences at the Federal Institute of Education of Amapa/AP, where the electronic waste was used in an Environmental Education and Art perspective, adding knowledge of both areas in the objects produced by the students of the technical course of agriculture at the Porto Grande campus. We use the principles of participant survey, where those involved in research become agents of their reality transformation, in a critical way. Through lectures, speeches and art workshops, students were encouraged to produce objects of art that culminated in an exhibition for the community. We can conclude that the concepts of art can and should be added to the objectives of environmental education, so the society can mitigate the impacts caused to the environment by the increasing production of electronic rests. / A produ??o de res?duos de eletr?nicos se apresenta como um grande desafio a ser enfrentado pelos ?rg?os p?blicos municipais, estaduais e federais no Brasil. Os Institutos Federais est?o inseridos nesse cen?rio e devem buscar formas de colaborar para diminuir a produ??o desses res?duos e encontrar formas conscientes de aproveitamento dos mesmos. Nesse sentido, a Educa??o Ambiental aliada ? Educa??o Art?stica pode contribuir na reutiliza??o de res?duos de inform?tica nos Institutos. O objetivo da presente pesquisa foi o de desenvolver experi?ncias no Instituto Federal de Educa??o do Amap?/AP, onde os res?duos eletr?nicos foram utilizados numa perspectiva de Arte e Educa??o Ambiental, agregando conhecimentos de ambas as ?reas nos objetos produzidos por alunos do Curso de T?cnico em Agropecu?ria do campus Porto Grande. N?s utilizamos dos princ?pios da pesquisa participante, onde os envolvidos na pesquisa se tornam agentes de transforma??o da sua realidade, de forma cr?tica. Atrav?s de aulas expositivas, palestras e das oficinas de arte, os alunos foram estimulados a produzir objetos de arte que culminaram numa exposi??o para a comunidade. Podemos concluir que os conceitos de arte podem e devem ser agregados aos objetivos da Educa??o Ambiental de forma que a sociedade possa mitigar os impactos causados ao meio ambiente pela crescente produ??o de res?duos eletr?nicos.
2

Caracteriza??o de placas de circuito impresso oriundas de telefones celulares e recupera??o de cobre / Circuit boards printed characterization coming from mobile phones and copper recovery

Jesus, Theo Antonio de 23 January 2015 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-01T14:05:35Z No. of bitstreams: 1 2015 - Theo Antonio de Jesus.pdf: 3265233 bytes, checksum: 84b1c9854e0877f1a010f74527aca2e5 (MD5) / Made available in DSpace on 2017-06-01T14:05:35Z (GMT). No. of bitstreams: 1 2015 - Theo Antonio de Jesus.pdf: 3265233 bytes, checksum: 84b1c9854e0877f1a010f74527aca2e5 (MD5) Previous issue date: 2015-01-23 / Technological advances encourages the constant exchange of electronic equipment by increasing the amount of waste generated. The concern with the disposal of these wastes is related to the amount of available metals and final disposal, which usually occurs in dumps or landfills. These wastes have precious metals and other trace elements that are released into the environment by leaching from the organic acid attack. Most of these residues has printed circuit boards in which are concentrated the most metals, and the characterization of these plates help to choose the most appropriate recycling processes. This study aimed to characterize the printed circuit boards of mobile phones as its danger and composition as well as preliminarily investigate the possibility of copper recovery via an electrolytic process and test a mixture of coagulant / flocculant in the removal of metals, including copper. The plates were ground knives in order to release the metals and then separating the particle size was made in three fractions of different sizes. Each of the fractions was characterized by digestion in aqua regia, diffraction and X-ray fluorescence characterization, as the danger was performed through recommended by the ABNT NBR 10005. In the fractions resulting from the grain size were performed gravity separations. For the recovery of copper was used in electrolytic technique medium prepared with the electrolyte coming from the gravimetric fraction with a higher concentration of metals. The copper recovery efficiency through electrolytic process was evaluated by the decrease of its concentration in the electrolyte at five different times. Also, the use of coagulant mixture / flocculant had their efficiency assessed by check which proportion coagulant / flocculant used resulted in solution with lower concentrations of metals. It is also made of copper recovery compared by both methods. Mechanical processes are used to promote adequate concentration of most metals with approximately 80% in the coarser fraction using the separation grain size. The characterization results showed that the printed circuit boards of mobile phones are rich in copper, mean values reaching 40%, in addition to having small amounts of gold and silver. In the study of danger, lead levels were found in amounts well above the limit established by ABNT NBR 10004, requiring specific treatments at the disposal of this type of waste. Some proportions coagulant / flocculant used produced better results than others, getting, on average, above 90% removal. The recovery of copper showed better performance using the electrolytic process, compared to that obtained at any ratio coagulant / flocculant used once reached 98.05 % after 40 minutes. It was estimated the average revenue generated in the recovery of metals from the main printed circuit boards of mobile phones discarded in 2013 in Brazil, reaching the amount of US $ 6,182,263.06 / O avan?o tecnol?gico incentiva a troca constante dos equipamentos eletroeletr?nicos aumentando a quantidade de res?duos gerados. A preocupa??o com a disposi??o desses res?duos est? relacionada com a quantidade de metais existentes e sua disposi??o final, que geralmente se d? em lix?es ou aterros. Estes res?duos apresentam metais preciosos e outros elementos tra?os que s?o liberados no meio ambiente pela lixivia??o proveniente do ataque de ?cidos org?nicos. A maior parte destes res?duos possui placas de circuito impresso onde est? concentrada a maior parte dos metais, sendo que a caracteriza??o destas placas ajuda na escolha dos processos de reciclagem mais adequados. Este trabalho teve como objetivo caracterizar as placas de circuito impresso de telefones celulares quanto sua periculosidade e composi??o, bem como investigar preliminarmente a possibilidade de recupera??o de cobre via um processo eletrol?tico e testar uma mistura de coagulante/floculante na remo??o de metais, inclusive cobre. As placas foram processadas em moinho de facas, a fim de liberar os metais e, em seguida, foi feita a separa??o granulom?trica em tr?s fra??es de diferentes tamanhos. Cada uma das fra??es foi caracterizada por digest?o em ?gua r?gia, difra??o e fluoresc?ncia de raios X. A caracteriza??o, quanto ? periculosidade, foi realizada por meio do preconizado pela NBR ABNT 10005. Nas fra??es oriundas da granulometria foram realizadas as separa??es gravim?tricas. Para a recupera??o de cobre foi utilizada a t?cnica eletrol?tica por meio de eletr?lito preparado com a fra??o oriunda da gravimetria com maior concentra??o de metais. A efici?ncia da recupera??o de cobre via processo eletrol?tico foi avaliada por meio da diminui??o de sua concentra??o no eletr?lito em cinco tempos diferentes. J? a utiliza??o da mistura coagulante/floculante teve sua efici?ncia avaliada pela verifica??o de qual propor??o coagulante/floculante utilizada resultou em solu??o com menor concentra??o de metais. Fez-se tamb?m a compara??o de recupera??o de cobre por ambos os m?todos. Os processos mec?nicos utilizados foram adequados para promoverem a concentra??o da maioria dos metais alcan?ando cerca de 80 % na fra??o mais grosseira utilizando-se a separa??o granulom?trica. Os resultados da caracteriza??o mostraram que as placas de circuito impresso de celulares s?o ricas em cobre, alcan?ando valores m?dios de 40 %, al?m de apresentarem pequenas quantidades de ouro e prata. No estudo de periculosidade, foram encontrados n?veis de chumbo em quantidades muito acima do limite estabelecido pela NBR ABNT 10004, sendo necess?rios tratamentos espec?ficos no descarte deste tipo de res?duo. Algumas propor??es de coagulante/floculante utilizadas produziram resultados mais satisfat?rios que outras, ficando, na m?dia, acima dos 90 % de remo??o. A recupera??o de cobre apresentou melhor desempenho utilizando processo eletrol?tico, quando comparado ao obtido a qualquer propor??o de coagulante/floculante utilizada, uma vez que alcan?ou 98,05 % ap?s 40 minutos. Foi estimada a receita m?dia gerada, na recupera??o dos principais metais contidos nas placas de circuito impresso dos telefones celulares, descartados em 2013, no Brasil, chegando-se ao valor de US $ 6.182.263,06.
3

Separa??o de metais com alto valor agregado a partir de placas de circuito impresso

Souza, Wagner Barbosa de January 2016 (has links)
Data de aprova??o ausente. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-03-29T18:49:58Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) wagner_barbosa_souza.pdf: 2617971 bytes, checksum: 3d7e6b01cafdb0a61d93af504071663c (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-04-24T16:36:52Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) wagner_barbosa_souza.pdf: 2617971 bytes, checksum: 3d7e6b01cafdb0a61d93af504071663c (MD5) / Made available in DSpace on 2017-04-24T16:36:52Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) wagner_barbosa_souza.pdf: 2617971 bytes, checksum: 3d7e6b01cafdb0a61d93af504071663c (MD5) Previous issue date: 2016 / Com o avan?o exponencial da ind?stria de eletr?nicos, o consumo destes produtos tamb?m est? crescendo largamente. Com isso, os descartes destes equipamentos tamb?m crescem na mesma propor??o. Por ano, no mundo, estima-se que mais de 25 milh?es de toneladas de lixo eletr?nico sejam descartadas. Neste trabalho foi desenvolvido um novo m?todo hidrometal?rgico ambientalmente seguro para a extra??o seletiva de cobre, n?quel e prata provenientes de res?duos de placas de circuito impresso (PCI), empregando Sistemas Aquosos Bif?sicos (SAB) como t?cnica de extra??o. O comportamento de extra??o dos ?ons met?licos Cu (II), Ni(II), Fe(III) e Ag(I)em SAB formado por copol?mero tribloco L64 + MgSO4 + H2O foi avaliado para a otimiza??o do m?todo, verificando a influ?ncia dos seguintes par?metros experimentais sobre a extra??o dos analitos: valores de pH do SAB (3,0; 6,0; 9,0 e 11,0); natureza e concentra??o dos agentes extratores 1-(2-piridil-azo)-2-naftol (PAN) para os estudo de extra??o do Cu(II), 1-nitroso-2-naftol (1N2N) e dimetilglioxima (DMG) para a extra??o do ?on Ni(II), tiocianato (SCN) e ditizona (Dz) para a extra??o da Ag(I). A efici?ncia de recupera??o seletiva dos metais foi avaliada por meio da an?lise da porcentagem de extra??o (%E) e do fator de separa??o (S) entre os ?ons de interesse. As melhores condi??es para extra??o seletiva foram: PAN [3,5 mmol.Kg-1] em pH = 6,0 em 6 etapas consecutivas para separa??o do Cu(II), DMG [5,00 mmol.Kg-1] em pH = 9,0 para o Ni(II) e SCN[5,20 mmol.Kg-1] em pH = 9,0 para a Ag(I) . Em todas as situa??es foram obtidos valores de fator de separa??o(S) entre o analito e os concomitantes met?licos maiores que 103. As condi??es ?timas obtidas foram aplicadas ao lixiviado de PCI para a extra??o de cobre, n?quel e prata de forma sequencial, obtendo-se altos valores de S entre o analito e os concomitantes met?licos (SCu,Ni= 1,46 x 103, SCu,Fe= 1,55 x 104, SCu,Ag= 1,59 x 104, SNi,Fe= 3,27 x 104, SNi,Ag= 3,47 x 104 eSAg,Fe= 4,80 x 103).Ap?s a extra??o de cada metal foi realizado um estudo de stripping em uma ?nica etapa, onde 89,5%, 92,5% e 82,5% de Cu(II), Ni(II) e Ag(I), respectivamente foram disponibilizados para a etapa de eletrodeposi??o. Portanto o m?todo utilizando SAB se mostrou eficiente e dentro dos princ?pios da qu?mica verde, pois utiliza componentes at?xicos, biodegrad?veis e recicl?veis e de r?pida separa??o de fases sem a forma??o de emuls?es est?veis. Sendo um m?todo alternativo para a extra??o liquido ? liquido tradicional. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, [2016]. / With the exponential advancement of electronic industry, the consumption of these products is also growing wide. With this, the drops of this equipment also grow at the same rate. A year in the world, it is estimated that more than 25 million tons of electronic waste are disposed.This work developed a new environmentally safe hydrometallurgical method for the selective extraction of copper, nickel and silver from waste printed circuit board (PCB) using Aqueous Two-Phase Systems (SAB) as extraction technique. The extraction behavior of metal ions Cu (II), Ni (II), Fe (III) and Ag (I) SAB formed by tri-block copolymer L64 + MgSO4 + H2O was evaluated for the optimization of the method by checking the influence of the following experimental parameters on the extraction of analytes: the SAB pH (3.0, 6.0, 9.0 and 11.0); nature and concentration of agents extractors 1- (2-pyridyl-azo) -2-naphthol (PAN) Cu for the extraction method (II), the 1-nitroso-2-naphthol (1N2N) and dimethylglyoxime (DMG) for ion extraction Ni (II), thiocyanate (SCN) and dithizone (Dz) for the extraction of Ag (I).The selective metal recovery efficiency was evaluated by the percentage extraction analysis (% E) and separation factor (S) between the ions of interest. The best conditions for selective extractions were NAP [3,5 mmol.Kg-1] at pH 6.0 in 6 consecutive stages for separation of Cu (II) DMG [5.00 mmol.Kg-1] pH = 9.0 for Ni (II) and SCN [5,20 mmol.Kg-1] at pH = 9.0 for Ag (I). In all cases they were obtained separation factor values (S) between the analyte and the larger metal Concomitant 103. The obtained optimum conditions were applied to the PCI leached copper extraction, nickel and silver sequentially, yielding if high S values between the analyte and the metal concomitant (SCU, Ni = 1.46 x 103, SCU, Fe = 1.55 x 104, SCU, Ag = 1.59 x 104, SNI, Fe = 3.27 x 104, SNI, Ag = 3.47 x 104 and SAg, Fe = 4.80 x 103).After extraction of each metal it was made a study stripping in one step, where 89.5%, 92.5% and 82.5% Cu (II), Ni (II) and Ag (I), respectively, were available for the electroplating step. Therefore, the method using BSA was efficient and within the principles of green chemistry, because it uses non-toxic, biodegradable and recyclable and fast phase separation without the formation of stable emulsions components. As an alternative method for liquid - liquid extraction traditional.

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