Back to Search
Start Over
EVALUATION OF THE CHEMICAL COMPOSITION AND STRUCTURE OF ASPHALTENES FROM THREE OFFSHORE BRAZILIAN BIODEGRADED HEAVY OILS
- Source :
- Química Nova, Vol 44, Iss 4, Pp 391-401 (2021)
- Publication Year :
- 2021
- Publisher :
- Sociedade Brasileira de Química, 2021.
-
Abstract
- Asphaltenes fractions were extracted and purified from three heavy Brazilian oils. Their mass compositions of C, H, N, Ni and V were obtained from elemental analysis and S and O atomic percentages from EDS. The H/C ratios showed high degree of unsaturation, while the O atomic percentages indicated more pronounced biodegradation effects on two samples. Quantitative data on N, Ni, and V and semi-quantitative data on S were related to oils origins. The structural data of asphaltenes were explored by combining Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H NMR). The oil with the lower degree of biodegradation contained asphaltenes with a lower level of condensed aromatic rings and longer aliphatic chain substituents. The asphaltenes obtained from the two most biodegraded oils showed similarities of polar groups and the presence of carboxylic functions, as well as lower contents of aliphatic substituents. The quality and quantity of occluded hydrocarbons were assessed after the mild oxidation of the separated asphaltenes fractions. It was suggested that the severe biodegradation which altered these structures may also be responsible to affect their occluded hydrocarbons.
- Subjects :
- asphaltene
heavy oil
biodegradation
occluded hydrocarbon
Chemistry
QD1-999
Subjects
Details
- Language :
- English, Spanish; Castilian, Portuguese
- ISSN :
- 16787064 and 01004042
- Volume :
- 44
- Issue :
- 4
- Database :
- Directory of Open Access Journals
- Journal :
- Química Nova
- Publication Type :
- Academic Journal
- Accession number :
- edsdoj.21bf365ff8d442d6a93023873c046fec
- Document Type :
- article
- Full Text :
- https://doi.org/10.21577/0100-4042.20170697