Chemical Composition and Microstructure of Bitumen – a Matter of Terminology?
Bitumen is an organic material derived from crude oil refinery. It exhibits a highly complex chemical composition, time- and temperature dependent viscoelastic material behavior and distinct microstructural features. Ongoing efforts try to link these three material characteristics by combining physico-chemical with mechanical analysis. Two different theses that explain which chemical constituents trigger the materials’ microstructure: one group of researchers is in favor of the idea that waxes are responsible, the other group favors asphaltenes as the crucial factor. Both groups base their assumptions on experimental evidence. However, no final proof for either theses exists. A recent study on high mass resolution analysis of bitumen and its constituents shows that in fact both groups might be referring to the same thing and simply using different terminology. This paper suggests a temporary solution for overcoming the differences by substituting the controversial terms “wax” and “asphaltene” by the more general but still correct term “n-heptane insolubles” for the time being.
KeywordsBitumen Microstructure Composition Chemo-mechanics Asphaltenes Waxes
- Handle, F., Fussl, J., Neudl, S., Grossegger, D., Eberhardsteiner, L., Hofko, B., Hospodka, M., Blab, R., Grothe, H.: Understanding the microstructure of bitumen: a CLSM and fluorescence approach to model bitumen ageing behavior. In: Asphalt Pavements, vol. 1, no. 2, pp. 521–530 (2014)Google Scholar
- Handle, F., Harir, M., Fussl, J., Kosyun, A.N., Grossegger, D., Hertkorn, N., Eberhardsteiner, L., Hofko, B., Hospodka, M., Blab, R., Schmitt-Kopplin, P., Grothe, H.: Tracking aging of bitumen and its saturate, aromatic, resin, and asphaltene fractions using high-field fourier transform ion cyclotron resonance mass spectrometry. Energy Fuels 31(5), 4771–4779 (2017)CrossRefGoogle Scholar
- Soenen, H., Besamusca, J., Fischer, H.R., Poulikakos, L.D., Planche, J.P., Das, P.K., Kringos, N., Grenfell, J., Lu, X., Chailleux, E.: Laboratory investigation of bitumen based on round robin DSC and AFM tests. Mater. Struct. 47, 1–16 (2013)Google Scholar
- Yarranton, H.W., Ortiz, D.P., Barrera, D.M., Baydak, E.N., Barre, L., Frot, D., Eyssautier, J., Zeng, H., Xu, Z., Dechaine, G., Becerra, M., Shaw, J.M., McKenna, A.M., Mapolelo, M.M., Bohne, C., Yang, Z., Oake, J.: On the size distribution of self-associated asphaltenes. Energy Fuels 27(9), 5083–5106 (2013)CrossRefGoogle Scholar