Menkiti N D, Isanbor C, Ayejuyo O O
Department of Chemistry, Ahmadu Bello University Zaria Nigeria
Department of Chemistry, University of Lagos Akoka Nigeria.
RSC Adv. 2025 Jun 4;15(24):18910-18919. doi: 10.1039/d5ra00826c.
Eight oil residues extracted from crude oil spill sites have been investigated for natural attenuation using heteronuclear single quantum coherence nuclear magnetic resonance spectroscopy (2D HSQC NMR). Using the exploratory data analysis (EDA) techniques; principal component analysis (PCA) and hierarchical cluster analysis (HCA), the predictive ability of the NMR technique with respect to similarities and differences in the composition of the oil residue over time was explored. The first three PCs from PCA accounted for 87% of the total variance while three clusters each were obtained from HCA analysis based on similarity in samples and NMR areas. Both exploratory analyses revealed that the -CH/-CH types, aliphatic, and aromatic content of the oil residue are the main factors responsible for compositional differences. The Euclidean distance constructed from PCA indicated real differences between fresh crude oil, aged, and younger residue. If the exposure time of the oil spill is known, HSQC coupled with exploratory data analysis would be a useful tool in evaluating the structural and compositional transformation of oil residue in the environment. This may be useful as a guide in deciding which remediation strategy is implemented in an oil spill environment like the Niger Delta region.
利用异核单量子相干核磁共振波谱法（二维HSQC NMR）对从原油泄漏现场提取的8种油类残留物进行了自然衰减研究。运用探索性数据分析（EDA）技术，即主成分分析（PCA）和层次聚类分析（HCA），探究了NMR技术对油类残留物成分随时间变化的异同的预测能力。PCA的前三个主成分占总方差的87%，而基于样本和NMR区域的相似性，HCA分析得到了三个聚类。两种探索性分析均表明，油类残留物的-CH/-CH类型、脂肪族和芳香族含量是造成成分差异的主要因素。由PCA构建的欧氏距离表明新鲜原油、老化和较年轻残留物之间存在实际差异。如果已知溢油的暴露时间，HSQC结合探索性数据分析将成为评估环境中油类残留物结构和成分变化的有用工具。这对于决定在尼日尔三角洲地区这样的溢油环境中实施哪种修复策略可能具有指导作用。
