Characteristic of Oil Products in Bottom Sediments in Lake Pyasino by GC/MS Method

Abstract

The integral methods commonly used to determine oil products, such as gravimetric, IR-photometric, and fluorescent do not take into account the nature of the analyzed compounds and the contribution of biogenic hydrocarbons, the assessment of which requires more detailed analysis, which can be made by GC/MS method. The oil products in Lake Pyasino bottom sediments show the presence of n-alkanes with a considerable predominance of C17 n-alkane and a small predominance of n-C₁₂, n-C₁₄, n-C₁₆, and n-C₁₈, reflecting the contribution of microorganisms and algae, as well as the predominance of n-C₂₃, n-C₂₅, n-C₂₇, n-C₂₉, n-C₃₁ due to the contribution of higher terrestrial plants. The chromatogram contains two “humps” of nonseparated compounds in the C₁₀−C₂₁ and C₂₂−C₃₃ regions. Oil products in them are mixtures of alkanes, cycloalkanes with 1–4 rings in a condensed system, and aromatic and naphthene-aromatic hydrocarbons with 1–3 benzol and 1–2 saturated rings in the condensed system, with alkyl substituents containing 0–12 (mostly, 2–8) C atoms.