Imperial College London

Professor Erich A. Muller

Faculty of EngineeringDepartment of Chemical Engineering

Professor of Thermodynamics
 
 
 
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Contact

 

+44 (0)20 7594 1569e.muller Website

 
 
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Assistant

 

Miss Raluca Leonte +44 (0)20 7594 5557

 
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Location

 

409ACE ExtensionSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Headen:2017:10.1021/acs.energyfuels.6b02161,
author = {Headen, T and Boek, E and Jackson, G and Totton, T and Muller, EA},
doi = {10.1021/acs.energyfuels.6b02161},
journal = {Energy & Fuels},
pages = {1108--1125},
title = {Simulation of asphaltene aggregation through molecular dynamics: insights and limitations},
url = {http://dx.doi.org/10.1021/acs.energyfuels.6b02161},
volume = {31},
year = {2017}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - We report classical atomistic molecular dynamics simulations of four structurally diverse model asphaltenes, a model resin,and their respective mixtures in toluene or heptane at ambient conditions. Relatively large systems (~50,000 atoms) and long timescales(> 80 ns)are explored. Whereever possible,comparisons are madeto available experimental observations asserting the validity of the models. When the asphaltenes are dissolved in toluene, a continuous distribution of cluster sizesis observed with average aggregation number ranging between 3.6and 5.6,monomers and dimers being thepredominantspecies. As expected for mixtures in heptane the asphaltene molecules tend to aggregate to form a segregated phase. There is no evidence of a distinct formation of nanoaggregates, the distributions of clusters is found to becontinuous in character.The analysis of the shape of the clusters of asphaltenes suggests that they are generally spherical incharacter, with the archipelago models favouring longer prolate structuresand the continental modeltending towards oblate structures. The aggregates areseen to bediffuse in nature, containing at least 50% solventon average, being denser in heptane than in toluene. Mixtures of asphaltenes with different architectureare found to have cluster properties that are intermediate between those of the individual components. The presence of resins in the mixture does not appear to alter the shape of the asphaltene aggregates, their size or density when toluene is the solvent; on the otherhand theresins lead to an increase in the density of the resulting aggregatesin heptane. Quantification of these observations is made from the histograms of cluster distributions, the potential of mean force calculations,and an analysis of the shape factors. We illustrate howthe time scales for complete aggregationof molecules in heptanearelarger t
AU - Headen,T
AU - Boek,E
AU - Jackson,G
AU - Totton,T
AU - Muller,EA
DO - 10.1021/acs.energyfuels.6b02161
EP - 1125
PY - 2017///
SN - 1520-5029
SP - 1108
TI - Simulation of asphaltene aggregation through molecular dynamics: insights and limitations
T2 - Energy & Fuels
UR - http://dx.doi.org/10.1021/acs.energyfuels.6b02161
UR - http://hdl.handle.net/10044/1/43754
VL - 31
ER -