Determinação de elementos terras raras em amostras ambientais por cromatografia líquida de alta eficiência com pareamento iônico
Ano de defesa: | 2018 |
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Autor(a) principal: | |
Orientador(a): | |
Banca de defesa: | , , , |
Tipo de documento: | Tese |
Tipo de acesso: | Acesso aberto |
Idioma: | por |
Instituição de defesa: |
Universidade Federal de Santa Maria
Centro de Ciências Naturais e Exatas |
Programa de Pós-Graduação: |
Programa de Pós-Graduação em Química
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Departamento: |
Química
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País: |
Brasil
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Palavras-chave em Português: | |
Palavras-chave em Inglês: | |
Área do conhecimento CNPq: | |
Link de acesso: | http://repositorio.ufsm.br/handle/1/15660 |
Resumo: | Rare earth elements (ETRs) comprise a group of 17 chemical elements formed by the series of lanthanides, from lanthanum (La) to lutetium (Lu), added to scandium (Sc) and yttrium (Y) elements. Currently they are widely used in the manufacture of high technology products such as LED televisions, smartphones, electric vehicles as well as clean energy generation (wind and solar). Lately, ETR production is concentrated in China, controlling the global supply of the raw material. Currently, Brazil (and other countries) is seeking the resumption of the acquisition processes and the search for new mining areas of ETR. In the present work, the city of Lavras do Sul is investigated as a possible zone of obtaining ETR, being considered one of the regions with the highest concentration of minerals in the state of Rio Grande do Sul. For this purpouse a chromatographic method was developed and validated in terms of the main analytical characteristics for the determination of 15 rare earth elements (La to Lu and Y) using high-performance liquid chromatography with ion-pairing and post-column derivatization in water and soil samples. The calculated values of the instrumental detection limits ranged from 0.023 to 0.158 μg mL-1, for the most sensitive analyte (Dy) at least sensitive (La), respectively. Similarly, the calculated values of the instrumental quantification limits ranged from 0.069 μg mL-1 (Dy) to 0.480 μg mL-1 (La). Intra-day precision presented relative standard deviation values ranging from 0.22% (Ho) to 4.08% (La) and, inter-day, ranging from 1.07% (Yb) to 4.86% (La). During the evaluation of the selectivity of the method, it was found that Ni, Cu, Zn and Pb caused interferences in the determination of the ETR, since they formed absorbing complexes with the PAR complexing agent (used in post-column derivatization) and had retention times similar to those of the analytes. In this way, procedures for the removal of interferents were investigated. For the determination of ETR in samples (natural and artificial) of water, a procedure using ion exchange mini-columns proved to be efficient. Metal ions in solution were previously adsorbed on strongly acid cationic resin. Interferences were initially eluted with 15 mL of HCl (1 mol L-1). The ETRs were removed from the column, as a single set, with 13 mL of HNO3 (6 mol L-1, 50 ⁰C). For the determination of ETR in natural soil samples, a procedure by fractional precipitation was applied. After the mineralization of the samples (1.0 g of mass with 10 mL of concentrated HNO3 in a heated block at 90 ± 5 ⁰C for 72 hours with a final volume of 40 mL by the addition of ultrapure water), the interfering elements were separated from the ETR by precipitation of their respective insoluble hydroxides, through successive adjustments of the pH value of the sample (with NH4OH). The insoluble hydroxides of the ETR were obtained in pH values from 6.0 to 8.5. After centrifugation and filtration steps, the precipitates containing the ETR were redissolved in HNO3 (2 mL, 2 mol L-1) and were thus free of interferents. Under these conditions a 20-fold preconcentration factor was achieved. The results determined in the water and soil samples were compared with a reference method (ICP-MS), demonstrating that the proposed chromatographic method generates reliable results for the determination of the 15 ETRs (La a Lu and Y). |
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2019-02-15T14:26:43Z2019-02-15T14:26:43Z2018-08-28http://repositorio.ufsm.br/handle/1/15660Rare earth elements (ETRs) comprise a group of 17 chemical elements formed by the series of lanthanides, from lanthanum (La) to lutetium (Lu), added to scandium (Sc) and yttrium (Y) elements. Currently they are widely used in the manufacture of high technology products such as LED televisions, smartphones, electric vehicles as well as clean energy generation (wind and solar). Lately, ETR production is concentrated in China, controlling the global supply of the raw material. Currently, Brazil (and other countries) is seeking the resumption of the acquisition processes and the search for new mining areas of ETR. In the present work, the city of Lavras do Sul is investigated as a possible zone of obtaining ETR, being considered one of the regions with the highest concentration of minerals in the state of Rio Grande do Sul. For this purpouse a chromatographic method was developed and validated in terms of the main analytical characteristics for the determination of 15 rare earth elements (La to Lu and Y) using high-performance liquid chromatography with ion-pairing and post-column derivatization in water and soil samples. The calculated values of the instrumental detection limits ranged from 0.023 to 0.158 μg mL-1, for the most sensitive analyte (Dy) at least sensitive (La), respectively. Similarly, the calculated values of the instrumental quantification limits ranged from 0.069 μg mL-1 (Dy) to 0.480 μg mL-1 (La). Intra-day precision presented relative standard deviation values ranging from 0.22% (Ho) to 4.08% (La) and, inter-day, ranging from 1.07% (Yb) to 4.86% (La). During the evaluation of the selectivity of the method, it was found that Ni, Cu, Zn and Pb caused interferences in the determination of the ETR, since they formed absorbing complexes with the PAR complexing agent (used in post-column derivatization) and had retention times similar to those of the analytes. In this way, procedures for the removal of interferents were investigated. For the determination of ETR in samples (natural and artificial) of water, a procedure using ion exchange mini-columns proved to be efficient. Metal ions in solution were previously adsorbed on strongly acid cationic resin. Interferences were initially eluted with 15 mL of HCl (1 mol L-1). The ETRs were removed from the column, as a single set, with 13 mL of HNO3 (6 mol L-1, 50 ⁰C). For the determination of ETR in natural soil samples, a procedure by fractional precipitation was applied. After the mineralization of the samples (1.0 g of mass with 10 mL of concentrated HNO3 in a heated block at 90 ± 5 ⁰C for 72 hours with a final volume of 40 mL by the addition of ultrapure water), the interfering elements were separated from the ETR by precipitation of their respective insoluble hydroxides, through successive adjustments of the pH value of the sample (with NH4OH). The insoluble hydroxides of the ETR were obtained in pH values from 6.0 to 8.5. After centrifugation and filtration steps, the precipitates containing the ETR were redissolved in HNO3 (2 mL, 2 mol L-1) and were thus free of interferents. Under these conditions a 20-fold preconcentration factor was achieved. The results determined in the water and soil samples were compared with a reference method (ICP-MS), demonstrating that the proposed chromatographic method generates reliable results for the determination of the 15 ETRs (La a Lu and Y).Os elementos terras raras (ETR) compõem um grupo de 17 elementos químicos formado pela série dos lantanídeos, do lantânio (La) ao lutécio (Lu), somado aos elementos escândio (Sc) e ítrio (Y). Atualmente são amplamente utilizados na fabricação de produtos de alta tecnologia como televisores de LED, smartphones, veículos elétricos, bem como a geração de energia limpa (eólica e solar). Ultimamente a produção de ETR está concentrada na China, controlando o fornecimento mundial da matéria prima. Atualmente o Brasil (e outros países) busca(m) a retomada dos processos de obtenção e as buscas por novas zonas de mineração de ETR. No presente trabalho a cidade de Lavras do Sul é investigada como possível zona para a obtenção de ETR, uma vez que é considerada uma das regiões de maior concentração de minerais do estado do Rio Grande do Sul. Para isto um método cromatográfico foi desenvolvido e validado, em termos das principais características analíticas, para a determinação de 15 elementos terras raras (La ao Lu e Y) utilizando cromatografia líquida de alta eficiência com pareamento iônico e derivatização pós-coluna em amostras de água e solo. Os valores calculados dos limites de detecção instrumental variaram de 0,023 a 0,158 μg mL-1, para o analito mais sensível (Dy) ao menos sensível (La), respectivamente. De forma semelhante os valores calculados dos limites de quantificação instrumental variaram de 0,069 μg mL-1 (Dy) a 0,480 μg mL-1 (La). A precisão intra-dia, apresentou valores de desvio padrão relativo variando de 0,22% (Ho) a 4,08% (La) e, inter-dia, variando de 1,07% (Yb) a 4,86% (La). Durante a avaliação da seletividade do método foi verificado que Ni, Cu, Zn e Pb causavam interferência na determinação dos ETR, uma vez que formavam complexos absorventes com o agente complexante PAR (utilizado na derivatização pós-coluna) e apresentavam tempos de retenção semelhantes ao dos analitos. Desta forma procedimentos para a remoção dos interferentes foram investigados. Para a determinação de ETR em amostras (naturais e artificiais) de água, um procedimento usando mini-colunas de troca iônica mostrou ser eficiente. Íons metálicos em solução foram previamente adsorvidos em resina catiônica fortemente ácida. Os interferentes foram, inicialmente, eluídos com 15 mL de HCl (1 mol L-1). Os ETR foram removidos da coluna, como um único conjunto, com 13 mL de HNO3 (6 mol L-1, a 50 ⁰C). Para a determinação de ETR em amostras naturais de solo, um procedimento por precipitação fracionada foi aplicado. Após a mineralização das amostras (1,0 g de massa com 10 mL de HNO3 concentrado, em bloco digestor aquecido a 90 ± 5 ⁰C por 72h, com volume final de 40 mL por adição de água ultrapura) os elementos interferentes foram separados dos ETR por precipitação de seus respectivos hidróxidos insolúveis, através de sucessivos ajustes do valor de pH da amostra (com NH4OH). Os hidróxidos insolúveis dos ETR foram obtidos em valores de pH entre 6 a 8,5. Após etapas de centrifugação e filtração, os precipitados contendo os ETR foram redissolvidos em HNO3 (2 mL, 2 mol L-1) estando assim, livre dos interferentes. Nestas condições um fator de pré-concentração de 20 vezes foi alcançado. Os resultados determinados nas amostras de agua e solo foram comparados com um método de referência (ICP-MS), demonstrando que o método cromatográfico proposto gera resultados confiáveis para a determinação dos 15 ETR (La ao Lu e Y).porUniversidade Federal de Santa MariaCentro de Ciências Naturais e ExatasPrograma de Pós-Graduação em QuímicaUFSMBrasilQuímicaAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccessElementos terras rarasRP-HPLCIPC-DADDerivatização pós-coluna4-(2-piridilazo)resorcinolRare earth elementsIPC-DAD post-column derivatization4-(2-pyridylazo) resorcinolCNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICADeterminação de elementos terras raras em amostras ambientais por cromatografia líquida de alta eficiência com pareamento iônicoDetermination of rare earth elements in environmental samples by ion-pair tg chromatographyinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisNascimento, Paulo Cícero dohttp://lattes.cnpq.br/7151513617218161Dias, Daianehttp://lattes.cnpq.br/1610292752294501Santos, Marlei Veiga doshttp://lattes.cnpq.br/6139003759917394Mortari, Sergio Robertohttp://lattes.cnpq.br/7784609477475171Carvalho, Leandro Machado dehttp://lattes.cnpq.br/6652387343920028http://lattes.cnpq.br/3625853714790767Colim, Alexsandro Nunes100600000000600600578b51ed-b12f-4664-9b87-387ad073b32c07dba217-dace-45a3-9c6b-288014b3a2c2f31cd92f-1160-4b34-b56a-8d32d2c04171e283300d-ef89-4534-844f-b01c55a5e64a9f6ffcda-3f02-4b6c-9f1f-03883c27e383369e0f2d-1b60-4076-ac06-58a85a76f15breponame:Biblioteca Digital de Teses e Dissertações do UFSMinstname:Universidade Federal de Santa Maria (UFSM)instacron:UFSMCC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; 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dc.title.por.fl_str_mv |
Determinação de elementos terras raras em amostras ambientais por cromatografia líquida de alta eficiência com pareamento iônico |
dc.title.alternative.eng.fl_str_mv |
Determination of rare earth elements in environmental samples by ion-pair tg chromatography |
title |
Determinação de elementos terras raras em amostras ambientais por cromatografia líquida de alta eficiência com pareamento iônico |
spellingShingle |
Determinação de elementos terras raras em amostras ambientais por cromatografia líquida de alta eficiência com pareamento iônico Colim, Alexsandro Nunes Elementos terras raras RP-HPLC IPC-DAD Derivatização pós-coluna 4-(2-piridilazo)resorcinol Rare earth elements IPC-DAD post-column derivatization 4-(2-pyridylazo) resorcinol CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA |
title_short |
Determinação de elementos terras raras em amostras ambientais por cromatografia líquida de alta eficiência com pareamento iônico |
title_full |
Determinação de elementos terras raras em amostras ambientais por cromatografia líquida de alta eficiência com pareamento iônico |
title_fullStr |
Determinação de elementos terras raras em amostras ambientais por cromatografia líquida de alta eficiência com pareamento iônico |
title_full_unstemmed |
Determinação de elementos terras raras em amostras ambientais por cromatografia líquida de alta eficiência com pareamento iônico |
title_sort |
Determinação de elementos terras raras em amostras ambientais por cromatografia líquida de alta eficiência com pareamento iônico |
author |
Colim, Alexsandro Nunes |
author_facet |
Colim, Alexsandro Nunes |
author_role |
author |
dc.contributor.advisor1.fl_str_mv |
Nascimento, Paulo Cícero do |
dc.contributor.advisor1Lattes.fl_str_mv |
http://lattes.cnpq.br/7151513617218161 |
dc.contributor.referee1.fl_str_mv |
Dias, Daiane |
dc.contributor.referee1Lattes.fl_str_mv |
http://lattes.cnpq.br/1610292752294501 |
dc.contributor.referee2.fl_str_mv |
Santos, Marlei Veiga dos |
dc.contributor.referee2Lattes.fl_str_mv |
http://lattes.cnpq.br/6139003759917394 |
dc.contributor.referee3.fl_str_mv |
Mortari, Sergio Roberto |
dc.contributor.referee3Lattes.fl_str_mv |
http://lattes.cnpq.br/7784609477475171 |
dc.contributor.referee4.fl_str_mv |
Carvalho, Leandro Machado de |
dc.contributor.referee4Lattes.fl_str_mv |
http://lattes.cnpq.br/6652387343920028 |
dc.contributor.authorLattes.fl_str_mv |
http://lattes.cnpq.br/3625853714790767 |
dc.contributor.author.fl_str_mv |
Colim, Alexsandro Nunes |
contributor_str_mv |
Nascimento, Paulo Cícero do Dias, Daiane Santos, Marlei Veiga dos Mortari, Sergio Roberto Carvalho, Leandro Machado de |
dc.subject.por.fl_str_mv |
Elementos terras raras RP-HPLC IPC-DAD Derivatização pós-coluna 4-(2-piridilazo)resorcinol |
topic |
Elementos terras raras RP-HPLC IPC-DAD Derivatização pós-coluna 4-(2-piridilazo)resorcinol Rare earth elements IPC-DAD post-column derivatization 4-(2-pyridylazo) resorcinol CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA |
dc.subject.eng.fl_str_mv |
Rare earth elements IPC-DAD post-column derivatization 4-(2-pyridylazo) resorcinol |
dc.subject.cnpq.fl_str_mv |
CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA |
description |
Rare earth elements (ETRs) comprise a group of 17 chemical elements formed by the series of lanthanides, from lanthanum (La) to lutetium (Lu), added to scandium (Sc) and yttrium (Y) elements. Currently they are widely used in the manufacture of high technology products such as LED televisions, smartphones, electric vehicles as well as clean energy generation (wind and solar). Lately, ETR production is concentrated in China, controlling the global supply of the raw material. Currently, Brazil (and other countries) is seeking the resumption of the acquisition processes and the search for new mining areas of ETR. In the present work, the city of Lavras do Sul is investigated as a possible zone of obtaining ETR, being considered one of the regions with the highest concentration of minerals in the state of Rio Grande do Sul. For this purpouse a chromatographic method was developed and validated in terms of the main analytical characteristics for the determination of 15 rare earth elements (La to Lu and Y) using high-performance liquid chromatography with ion-pairing and post-column derivatization in water and soil samples. The calculated values of the instrumental detection limits ranged from 0.023 to 0.158 μg mL-1, for the most sensitive analyte (Dy) at least sensitive (La), respectively. Similarly, the calculated values of the instrumental quantification limits ranged from 0.069 μg mL-1 (Dy) to 0.480 μg mL-1 (La). Intra-day precision presented relative standard deviation values ranging from 0.22% (Ho) to 4.08% (La) and, inter-day, ranging from 1.07% (Yb) to 4.86% (La). During the evaluation of the selectivity of the method, it was found that Ni, Cu, Zn and Pb caused interferences in the determination of the ETR, since they formed absorbing complexes with the PAR complexing agent (used in post-column derivatization) and had retention times similar to those of the analytes. In this way, procedures for the removal of interferents were investigated. For the determination of ETR in samples (natural and artificial) of water, a procedure using ion exchange mini-columns proved to be efficient. Metal ions in solution were previously adsorbed on strongly acid cationic resin. Interferences were initially eluted with 15 mL of HCl (1 mol L-1). The ETRs were removed from the column, as a single set, with 13 mL of HNO3 (6 mol L-1, 50 ⁰C). For the determination of ETR in natural soil samples, a procedure by fractional precipitation was applied. After the mineralization of the samples (1.0 g of mass with 10 mL of concentrated HNO3 in a heated block at 90 ± 5 ⁰C for 72 hours with a final volume of 40 mL by the addition of ultrapure water), the interfering elements were separated from the ETR by precipitation of their respective insoluble hydroxides, through successive adjustments of the pH value of the sample (with NH4OH). The insoluble hydroxides of the ETR were obtained in pH values from 6.0 to 8.5. After centrifugation and filtration steps, the precipitates containing the ETR were redissolved in HNO3 (2 mL, 2 mol L-1) and were thus free of interferents. Under these conditions a 20-fold preconcentration factor was achieved. The results determined in the water and soil samples were compared with a reference method (ICP-MS), demonstrating that the proposed chromatographic method generates reliable results for the determination of the 15 ETRs (La a Lu and Y). |
publishDate |
2018 |
dc.date.issued.fl_str_mv |
2018-08-28 |
dc.date.accessioned.fl_str_mv |
2019-02-15T14:26:43Z |
dc.date.available.fl_str_mv |
2019-02-15T14:26:43Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/doctoralThesis |
format |
doctoralThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://repositorio.ufsm.br/handle/1/15660 |
url |
http://repositorio.ufsm.br/handle/1/15660 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.relation.cnpq.fl_str_mv |
100600000000 |
dc.relation.confidence.fl_str_mv |
600 600 |
dc.relation.authority.fl_str_mv |
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dc.rights.driver.fl_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Centro de Ciências Naturais e Exatas |
dc.publisher.program.fl_str_mv |
Programa de Pós-Graduação em Química |
dc.publisher.initials.fl_str_mv |
UFSM |
dc.publisher.country.fl_str_mv |
Brasil |
dc.publisher.department.fl_str_mv |
Química |
publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Centro de Ciências Naturais e Exatas |
dc.source.none.fl_str_mv |
reponame:Biblioteca Digital de Teses e Dissertações do UFSM instname:Universidade Federal de Santa Maria (UFSM) instacron:UFSM |
instname_str |
Universidade Federal de Santa Maria (UFSM) |
instacron_str |
UFSM |
institution |
UFSM |
reponame_str |
Biblioteca Digital de Teses e Dissertações do UFSM |
collection |
Biblioteca Digital de Teses e Dissertações do UFSM |
bitstream.url.fl_str_mv |
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repository.name.fl_str_mv |
Biblioteca Digital de Teses e Dissertações do UFSM - Universidade Federal de Santa Maria (UFSM) |
repository.mail.fl_str_mv |
atendimento.sib@ufsm.br||tedebc@gmail.com |
_version_ |
1793240122395721728 |