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Previous issue date: 2013-07-31 / In this paper, the technique of differential pulse voltammetry (DPV) has been
studied for monitoring the concentration of oxalic acid (OA) during their
electrochemical oxidation (EO) in acidic medium using platinum anode supported on
titanium (Ti / Pt). The DPV was standardized and optimized using a glassy carbon
electrode modified with cysteine. The modification with cysteine was developed
electrochemically, forming a polymeric film on the surface of the glassy carbon
electrode. The formation of the polymer film was confirmed by analysis of scanning
electron microscope and atomic force microscope, confirming the modification of the
electrode. The electrochemical degradation was developed using different current
densities 10, 20 30 and 40 mA cm -2 electrode with Ti / Pt observing the degradation
of oxalic acid, and monitored using the method of KMnO4 titration. However, the
analyzes with DPV showed the same behavior elimination of oxalic acid titration.
Compared with the titration method classical observed and DPV could be a good fit,
confidence limits of detection and confirming the applicability of the technique
electroanalytical for monitoring the degradation of oxalic acid / No presente trabalho, a t?cnica de voltametria de pulso diferencial (DPV) foi
estudada para o monitoramento da concentra??o de ?cido ox?lico (OA) durante a
sua oxida??o eletroqu?mica (EO) em meio ?cido utilizando o ?nodo de platina
suportada em tit?nio (Ti/Pt). A t?cnica de DPV foi padronizada e otimizada usando
um eletrodo de carbono v?treo modificado com ciste?na. A modifica??o com ciste?na
foi desenvolvida eletroquimicamente, formando um filme polim?rico na superf?cie do
eletrodo de carbono v?treo. A forma??o do filme polim?rico foi confirmada por an?lise
de Microsc?pio Eletr?nico de Varredura e Microsc?pio de For?a At?mica,
confirmando a modifica??o na superf?cie do eletrodo. A degrada??o eletroqu?mica foi
desenvolvida usando diferentes densidades de corrente, 10, 20 e 30 mA cm-? com
eletrodo de Ti/Pt, observando a degrada??o do ?cido ox?lico, sendo monitorado
empregando a metodologia de titula??o com KmnO4. No entanto, as an?lises com
DPV mostraram o mesmo comportamento de elimina??o do acido ox?lico,
observado com a titula??o. Comparado com o m?todo de titula??o cl?ssica e DPV
conseguiu-se um bom ajuste, intervalos de confian?a e limites de detec??o
confirmando a aplicabilidade da t?cnica eletroanal?tica para o monitoramento da
degrada??o de ?cido ox?lico
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17732 |
| Date | 31 July 2013 |
| Creators | Neves, Nathalia Costa Viana |
| Contributors | CPF:01139059980, http://lattes.cnpq.br/2485073932883264, Silva, Djalma Ribeiro da, CPF:13893734449, http://lattes.cnpq.br/2791074318745945, Souza, K?tia Regina, CPF:65561988468, Moura, Maria de F?tima Vit?ria de, CPF:31482015404, http://lattes.cnpq.br/2959800336802498, Huitle, Carlos Alberto Martinez |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Qu?mica, UFRN, BR, F?sico-Qu?mica; Qu?mica |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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