Chapter 2
The molecule size of asphaltenes ranges from 2 to 10 nm. Aggregates can
reach up to 100 μm. The critical concentration of aggregation is about 0.1 %, so
asphaltenes will aggregate even at very low concentration. Aggregation is thought
to take place by stacking of the planar polynuclear aromatic parts of the molecules,
probably due to π-π interactions or hydrogen bonding of the polar groups [2], as
shown in Figure 2.6.
Figure 2.5 Proposed structure Ofasphaltenes in Athabasca bitumen [24]
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