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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

Determina??o de CD, PB, e TL em ?gua produzida por HR-CS GF AAS ap?s extra??o em ponto nuvem / Determination of Cd, Pb, and Tl produced water by HR-CS GF AAS after extraction point in cloud

Bezerra, Breno Gustavo Porf?rio 03 November 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-26T17:52:57Z No. of bitstreams: 1 BrenoGustavoPorfirioBezerra_DISSERT.pdf: 1680172 bytes, checksum: 0f4f20935e8e24b12e505645455bea08 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-01-28T19:06:56Z (GMT) No. of bitstreams: 1 BrenoGustavoPorfirioBezerra_DISSERT.pdf: 1680172 bytes, checksum: 0f4f20935e8e24b12e505645455bea08 (MD5) / Made available in DSpace on 2016-01-28T19:06:56Z (GMT). No. of bitstreams: 1 BrenoGustavoPorfirioBezerra_DISSERT.pdf: 1680172 bytes, checksum: 0f4f20935e8e24b12e505645455bea08 (MD5) Previous issue date: 2014-11-03 / A ?gua produzida representa um grande problema associado com a atividade de extra??o de ?leo bruto. O monitoramento dos n?veis de metais nos res?duos ? constante e requer a utiliza??o de t?cnicas anal?ticas sens?veis. No entanto, a determina??o de elementos tra?o muitas vezes pode exigir uma etapa de pr?-concentra??o. O objetivo deste trabalho foi desenvolver um m?todo anal?tico simples e r?pido para a extra??o e pr?-concentra??o baseada no fen?meno de extra??o no ponto nuvem para a determina??o do Cd, Pb e Tl em ?gua produzida amostras por Espectrometria de Absor??o de alta resolu??o com fonte continua e atomiza??o em forno de grafite. Um planejamento Box Behnken foi usado para obter a condi??o ideal de extra??o dos analitos. Os fatores avaliados foram: concentra??o do agente complexante (o,odietilditilfosfato am?nio, DDTP), a concentra??o do ?cido clor?drico e concentra??o do surfactante (Triton X -114). A condi??o ideal de extra??o foi obtida com: 0,6% m v -1 DDTP, HCl 0,3 mol L-1 e 0,2% m v -1 de Triton X - 114 para o Pb; 0,7% m v -1 DDTP, HCl 0,8 mol L-1 e 0,2% m v -1 Triton X-114 para Cd. Para o Tl foi evidenciado que melhor condi??o de extra??o se d? com aus?ncia de DDTP, as condi??es de extra??o foram ent?o HCl 1,0 mol L-1 e 1,0% m v -1 de Triton X - 114. Os limites de detec??o para o m?todo proposto, foram 0,02 ?g L-1 , 0,004 ?g L-1 e 0,06 ?g L-1 para o Pb, Cd e Tl, respectivamente. Os fatores de enriquecimento foram superiores a 10 vezes. O m?todo foi aplicado para a ?gua produzida da bacia Potiguar, e testes de adi??o e recupera??o foram realizados, e valores ficaram entre 81% e 120%. A precis?o foi expressa com desvio padr?o relativo (RSD) foi inferior a 5% / Produced water is a major problem associated with the crude oil extraction activity. The monitoring of the levels of metals in the waste is constant and requires the use of sensitive analytical techniques. However, the determination of trace elements can often require a pre-concentration step. The objective of this study was to develop a simple and rapid analytical method for the extraction and pre-concentration based on extraction phenomenon cloud point for the determination of Cd, Pb and Tl in produced water samples by spectrometry of high resolution Absorption source continues and atomization graphite furnace. The Box Behnken design was used to obtain the optimal condition of extraction of analytes. The factors were evaluated: concentration of complexing agent (o,o-dietilditilfosfato ammonium, DDTP), the concentration of hydrochloric acid and concentration of surfactant (Triton X -114). The optimal condition obtained through extraction was: 0,6% m v-1 DDTP, HCl 0,3 mol L-1 and 0,2% m v-1 of Triton X - 114 for Pb; 0,7% m v-1 DDTP, HCl 0,8 mol L-1 and 0,2% m v-1 Triton X-114 for Cd. For Tl was evidenced that best extraction condition occurs with no DDTP, the extraction conditions were HCl 1,0 mol L-1 e 1,0% m v-1 de Triton X - 114. The limits of detection for the proposed method were 0,005 ?g L-1 , 0,03 ?g L-1 and 0,09 ?g L-1 to Cd, Pb and Tl, Respectively. Enrichment factors Were greater than 10 times. The method was applied to the water produced in the Potiguar basin, and addition and recovery tests were performed, and values were between 81% and 120%. The precision was expressed with relative standard deviation (RSD) is less than 5%

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