Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.753023
Title: Investigation of asphaltene aggregation with synthetic model compounds : an experimental and computational study
Author: Simionesie, Dorin
ISNI:       0000 0004 7426 130X
Awarding Body: University of Birmingham
Current Institution: University of Birmingham
Date of Award: 2018
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Abstract:
Aggregation of asphaltenes has attracted interest due to the impact on the crude-oil industry. Despite extensive studies on the molecular-structure of natural asphaltene, fundamental knowledge of their aggregation is incomplete. It is unclear how the driving forces of association are related to the molecular architecture and the solvent species, which ultimately affect the aggregation mechanism. In this dissertation, dynamic-light-scattering (DLS) experiments and molecular-dynamics (MD) simulations were performed to investigate the relation between asphaltene chemical-structure and solvent species. The model compounds studied isolate the driving forces of aggregation by varying the peripheral chain-length and functional-groups (triphenylene-cored models) in organic solvents. The results isolate the structure-function relationships. Increasing the chain length imposes restriction upon the nanoaggregate formation, while non-centrosymmetric models appear to be more prone to aggregation. Furthermore, polar components in asphaltene molecular-architecture are observed to increase aggregation potential, more than π-stacking. Hexabenzocoronene-cored models exhibit a structurally selective aggregation mechanisms, as the planar molecules are more liable to aggregate and precipitate than the non-planar models due to π-stacking hindrance. The motivation behind the development and testing of model polyaromatic compounds lies in the pursuit of isolating the source structural-dependence of the compounds interactions. This is done by assessing the solute-solute and solute-solvent associations by experimental and computational approaches, to underpin the structure-to-function relation dictated by aromatic and/or polar molecules in aromatic or aliphatic solvents. This dissertation provides insight for the aggregation of model compounds of varying molecular architectures, and sheds light on the intermolecular interactions affected by these variations and the solvent species.
Supervisor: Not available Sponsor: Engineering and Physical Sciences Research Council (EPSRC) ; University of Birmingham
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.753023  DOI: Not available
Keywords: TP Chemical technology
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