화학공학소재연구정보센터
Energy & Fuels, Vol.32, No.3, 2793-2800, 2018
Diffusion-Ordered Spectroscopy Nuclear Magnetic Resonance as an Alternative Technique to Improve Asphaltene Characterization
An asphaltene sample from a light Arabian crude oil was characterized using several analytical techniques, such as thermogravimetric analysis, nuclear magnetic resonance, Fourier transform infrared spectroscopy, and elemental analysis. The results showed that the sample has a high sulfur content and highly condensed aromatic compounds and the average molecular structure is predominantly of continental/island type; however, the presence of a significant amount of methylene carbons in long alkyl chains is clear. A diffusion-ordered spectroscopy nuclear magnetic resonance experiment (DOSY-NMR) was carried out to detect the presence of asphaltene aggregates, evaluate their size, and shed light on the presence of maltenic occluded species and entrained residual solvent. In the DOSY spectrum, some sample signals were attributed to non-asphaltenic molecules, showing that it is possible to achieve key features of the sample complexity in "one shot".