STRUCTURAL CHARACTERIZATION OF ASPHALTENES OBTAINED FROM HYDROPROCESSED CRUDE OILS BY SEM AND TEM

Asphaltenes from Maya crude and its hydroprocessed oils at different reaction conditions were precipitated and studied by scanning and transmission electron microscopy (SEM and TEM). In order to better understand the changes occured in asphaltene structure during hydroprocessing the crude oil fracti...

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Detalles Bibliográficos
Autores: TREJO, FERNANDO, ANCHEYTA, JORGE, RANA, MOHAN S.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:México
Institución:Instituto Politécnico Nacional
Repositorio:Repositorio Digital del IPN
OAI Identifier:oai:www.repositoriodigital.ipn.mx:123456789/10688
Acceso en línea:http://hdl.handle.net/123456789/169
http://www.repositoriodigital.ipn.mx/handle/123456789/10688
Access Level:acceso abierto
Palabra clave:Asphaltenes
Heavy crude
Hydrotreating
SEM and TEM
Descripción
Sumario:Asphaltenes from Maya crude and its hydroprocessed oils at different reaction conditions were precipitated and studied by scanning and transmission electron microscopy (SEM and TEM). In order to better understand the changes occured in asphaltene structure during hydroprocessing the crude oil fractionation procedure with solvents was used to separate asphaltenes based on their solubility properties. Different asphaltene morphologies were observed depending on the mixture of solvents used for fractionating asphaltenes and reaction conditions at which crude oil was hydroprocessed. A comparison between asphaltenes from hydroprocessed and pure Maya crude oil was carried out on the way to distinguish morphological changes at microscopic level. It was observed that removal of alkyl chains during hydroprocessing makes asphaltenes suffer a rearrangement in solid state favoring stacking of aromatic cores as determined by TEM. SEM microscopy allowed different fractions of asphaltenes for seeing that they are constituted by agglomerate particles, porous structures, and smooth surfaces.