Simultaneous spectrophotometric determination of La, Ho, Mn 5-Br-PADAP complexes using multivariate calibration with partial least-squares (PLS) data evaluation

A simple and fast analytical pocedure is proposed for the simultaneous spectrophotometric determination of lanthanum, holmium and manganese in synthetic ceramics, (La(0.8-x) Hox Sr0.2 MnO3), by using the partial least-squares (PLS) method. As chromogenic agent 5-Br-PADAP [2-(5 -bromo-2-pyridylazo)-5...

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Detalhes bibliográficos
Autores: Ferreyra, Raquel Edith, Camiña, José Manuel, Marchevsky, Eduardo Jorge, Luco, Juan Maria
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2000
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositório:CONICET Digital (CONICET)
Idioma:inglês
OAI Identifier:oai:ri.conicet.gov.ar:11336/100335
Acesso em linha:http://hdl.handle.net/11336/100335
Access Level:Acceso aberto
Palavra-chave:MULTIVARIATE
CALIBRATION
RARE EARTHS
SPECTROPHOTOMETRIC
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descrição
Resumo:A simple and fast analytical pocedure is proposed for the simultaneous spectrophotometric determination of lanthanum, holmium and manganese in synthetic ceramics, (La(0.8-x) Hox Sr0.2 MnO3), by using the partial least-squares (PLS) method. As chromogenic agent 5-Br-PADAP [2-(5 -bromo-2-pyridylazo)-5 -diethylaminophenol] was used, which form colored complexes with the three elements studied. To avoid metal hydrolysis, a mixture of ethanol and Triton X-100 at pH 9.5 was used for all experiments. A set of 17 calibration solutions measured throughout the 400-700 nm wavelength range was used in the calibration step. The concentration range for Mn(II) was 1-12 × 10-6 mol L-1, while the range for the rare earth elements La(III) and Ho(III) was 2-8 × 10-6 mol L-1. In order to demonstrate the applicability of the proposed method, a set of artificial samples containing the three analytes in variable proportions was prepared and analyzed. The analytical results obtained were quite acceptable with relative errors not greater than 7% in most cases.