Characterization of Algerian asphaltenes collected from several wells: asphaltene behavior in terms of flocculation and solubility

Even though there is a small amount of asphaltene in Algerian light oil (less than 0.7 weight percent), there is significant evidence that the issue of their precipitation during the oil production operations stems from the oil's chemical makeup, which influences the behavior of the asphaltene rather than the amount of asphaltene in the oil. An experimental analysis of the chemical structure of petroleum asphaltene samples from Algeria that were collected from numerous wells is presented in this paper. The samples were analyzed using elemental analysis and Fourier-transform infrared (FTIR) to ascertain the behavior of the asphaltene in terms of flocculation and solubility. The samples were all extracted using n-heptane at oil to solvent ratio of 1:40 (g/ml). Based on the elemental analysis, the results showed that the H/C atomic ratio of the Algerian Hassi-Messaoud asphaltene is found to range from 0.8 to 1.56. The first sample was more aromatic, meaning there were more substituted aromatic compounds, because it had the lowest H/C ratio value (0.8). These features were taken into account when comparing this sample to the other samples to determine that it has higher solubility degrees. For samples 1, 3, and 4, The H/C ratio's values are close to one. The H/C ratio (1.56) of the fifth sample was higher than the others, indicating a lower contribution from aromaticity compounds. Asphaltene has a heteroatom-rich structure when the O/C, S/C, or N/C atomic ratios are high. The most compact and heteroatom-rich aggregates are hence the first to flocculate. Because sample 2 had the greatest heteroatom content value of 6.79, this first aggregate was noted there. The Algerian asphaltene have lower sulfur content and a higher H/C ratio value. Various intensities of sulfoxide, aromatic, and aliphatic groups were detected by Fourier-Transform Infrared (FTIR). This investigation verified that asphaltene precipitation occurred in every oil field location in Hassi Messaoud.