Chemical Fingerprinting of Tricyclic Terpanes in Two Niger Delta Crude Oils and their Mixtures

Abstract: Gas chromatography system equipped with a mass selective detector was employed for chemical fingerprinting of two Niger Delta crude oils (samples A-001 and F-100) and their mixtures (samples B-208, C-406, D-604 and E-802) at different proportion. Total and individual abundances of C₁₉ to C₂₉ tricyclic terpanes, including C₂₄ tetracyclic terpane, detected in the six oil samples followed similar patterns, A-001 < E-802 < F-100 < B-208 < C-406 < D-604, indicating the abundances did not mix correspondingly with the proportion of the two Niger Delta crude oils. Pearson correlation suggested sample A-001 was genetically related to sample F-100 (76.03%), and the four mixtures were significantly similar to each other (99.00% - 99.90%) and sample F-100 (99.00% - 99.81%), and similar to sample A-001 (76.02% - 81.60%). Hierarchical cluster analysis (HCA) separated the tricyclic and tetracyclic terpanes detected into 2 main groups, which distinctly differed (strong negative correlation) in the variations of their compositions in the six crude oil samples. Plots show the compositions of HCA group-A and -B tricyclic terpanes decrease as the proportion of sample A-001 decrease, and  increase as the proportion of sample F-100 increase in the six crude oil samples, respectively. Values of the coefficient of determination (R²) for the tricyclic terpane plots, range from 0.1406 to 0.9113 for group-A and 0.1226 to 0.6081 for group-B, with the compositions of C₂₁ tricyclic terpane(d) being most suitable for use to estimate (91.13%) the proportion(s) of the two Niger Delta crude oils in their mixtures.

Keywords: Abundance, Correlation, Crude oil mixtures, Distribution, Niger Delta, Tricyclic terpane.

Title: Chemical Fingerprinting of Tricyclic Terpanes in Two Niger Delta Crude Oils and their Mixtures

Author: Mark O. Onyema

International Journal of Novel Research in Civil Structural and Earth Sciences

ISSN 2394-7357

Vol. 10, Issue 1, January 2023 - April 2023

Page No: 8-15

Novelty Journals

Website: www.noveltyjournals.com

Published Date: 25-April-2023

DOI: https://doi.org/10.5281/zenodo.7862509

Paper Download Link (Source)

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