Detalhes bibliográficos
| Ano de defesa: |
2007 |
| Autor(a) principal: |
Silva, Paulo Henrique Pereira da |
| Orientador(a): |
Faria, Ronaldo Censi
 |
| Banca de defesa: |
Não Informado pela instituição |
| Tipo de documento: |
Dissertação
|
| Tipo de acesso: |
Acesso aberto |
| Idioma: |
por |
| Instituição de defesa: |
Universidade Federal de São Carlos
|
| Programa de Pós-Graduação: |
Programa de Pós-Graduação em Química - PPGQ
|
| Departamento: |
Não Informado pela instituição
|
| País: |
BR
|
| Palavras-chave em Português: |
|
| Área do conhecimento CNPq: |
|
| Link de acesso: |
https://repositorio.ufscar.br/handle/20.500.14289/6438
|
Resumo: |
In this work a Cu/CuY2- indicator system was used to carry out potentiometric titrations of Cu2+, Co2+, Cd2+, Zn2+ and Mn2+ ions with EDTA solution. A copper wire with 8.32 cm2 of superficial area was used as an indicator electrode. The CuY2- complex was synthesized by reaction between cupric oxide (CuO) and EDTA standard solution (H2Y2-) at a temperature of 85 oC. The titrations were performed in the presence of small concentration of the CuY2- complex. The Cu2+, Co2+, Cd2+ and Zn2+ ions were titrated in sodium acetate buffer solution (pH 4.80) and Mn2+ in TRIS-HCl buffer solution (pH 8.90). A modification in a conventional method for titration of metallic cations with EDTA solutions was performed to improve the response of the system. The modification includes addition of buffer species to the titrant solution. The buffer specie used to prepare solutions was sodium acetate. The influence of the concentration of CuY2- added in the titration performance was investigated and a relation of nM2+/nCuY2- equal or greater than 5 should be used for a better response. During this work other studies were performed, such as the method to obtain carbonate-free sodium and potassium hydroxides solutions as well as the method for the standardization of EDTA solid reagent, Na2H2Y, to employing as secondary standard in the directly preparation of EDTA solution. |
