Assessment of the changes in the chemical composition of the crude oil spilled in the Kuwait desert after weathering for five years

The changes in the chemical composition of oil, weathered for five years in Kuwait oil lakes, were investigated. The oil samples were collected from the oil lakes, both in southern and northern oil fields. These changes were compared with those reported previously for the first 21 months of weathering for the oil samples from the same lakes. The results indicate that the asphaltene content of the oil remaining in the lakes or lake beds increased considerably. Saturates, for which a considerable loss was recorded in the first 21 months, increased over the last 39 months of weathering. On the other hand, the aromatic fraction of the oil decreased in most of the samples. The percentage of resins in the samples continued to increase steadily. Polycyclic aromatic hydrocarbons were also determined in all of the samples. In general, the concentration and overall composition did not change significantly. However, the higher (PAHs) did increase in their concentration.