Determinação voltamétrica de tiofenos, sulfetos, sulfóxidos e sulfonas em matrizes asfálticas empregando eletrodo de mercúrio

Sulfur compounds in petroleum asphalt cement (CAP) are related to quality parameters such as reactivity, corrosivity, pollution potential and are directly related to the aging of the asphalt. In this work, a voltammetric method was developed seeking to determine sulfur compounds in its reduced form...

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Detalles Bibliográficos
Autor: Silva, Chrys Katielli Hoinacki da
Tipo de recurso: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2016
País:Brasil
Institución:Universidade Federal de Santa Maria (UFSM)
Repositorio:Manancial - Repositório Digital da UFSM
Idioma:portugués
OAI Identifier:oai:repositorio.ufsm.br:1/10611
Acceso en línea:http://repositorio.ufsm.br/handle/1/10611
Access Level:acceso abierto
Palabra clave:Compostos sulfurados
Asfalto
Voltametria
Eletrodo de mercúrio
Sulfur compounds
Asphalt
Voltammetry
Mercury electrode
CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA
Descripción
Sumario:Sulfur compounds in petroleum asphalt cement (CAP) are related to quality parameters such as reactivity, corrosivity, pollution potential and are directly related to the aging of the asphalt. In this work, a voltammetric method was developed seeking to determine sulfur compounds in its reduced form (-II) and oxidized (+II, +IV) in virgin and aged CAP samples, using a mercury electrode in HMDE mode in a non-aqueous medium. To do so, sixteen sulfur compounds were studied in different oxidation states (-II, +II, +IV), obtaining the linear range and detection limit for each compound. The direct application of the method in the CAP samples is impossible due to the highly complex chemistry that the matrix presents, possibly making the determination of compounds not viable. Therefore, the CAP samples were fractionated into functional groups (saturated/aromatic, aliphatic sulfides and thiophenes) by the method adapted from Payzant (1989), employing redox reactions and chromatographic separation by adsorption on silica. After such fractionation, the samples were subjected to a cleaning procedure using solid phase extraction (SPE).