TY - JOUR

T1 - Biomarkers composition and polycyclic aromatic hydrocarbons (PAHs) characteristic of Bulgarian coals with different rank and origin

AU - Apostolova, Denitsa

AU - Bechtel, Achim

AU - Markova, Kalinka

AU - Kostova, Irena

PY - 2017

Y1 - 2017

N2 - Biomarker composition and polycyclic aromatic hydrocarbons (PAHs)concentrations of three coal samples from Bulgarian deposits of different rankare presented. The coal samples were taken from Stanyantsi, Bourgas and Dobroudja coal basins. Gas chromatography–mass spectrometry (GC-MS) wasapplied to assess organic matter source and to identify and quantify PAHs inthe studied samples. Coal rank was determined on the basis of vitrinite reflectance, Ro %.The alkane patterns of the three samples are dominated by long chainn-alkanes (C27-C31), usually found in higher terrestrial plants rich in cuticular waxes. With increasing rank, the odd over even predominance is significantly reduced and short-chain n-alkanes are present in higher quantities.Increased pristane/phytane ratios in the Dobroudja coals are attributed to theinfluence of coal rank on this parameter. Based on terpenoid biomarker composition, angiosperm-dominated vegetation is concluded for the Bourgas coalwhereas conifers dominated the peat-forming vegetation at Stanyantsi. Lowterpenoid biomarker concentration and high contents of alkylated naphthalenesand phenanthrenes in the bituminous coal reflect the diagenetic conversion ofthe plant-derived terpenoid hydrocarbons to alkylated PAHs. Highest PAHsconcentration was recorded in samples of higher rank (bituminous coal), and the lowest concentration was found in lignite samples. The examination of thePAHs composition revealed that 3 and 4 ring unsubstituted PAHs are dominant in the lignite and bituminous coal samples, whereas 4 and 5 ring PAHspredominate in subbituminous coal. We assume that the composition of PAHsin the extractable portion of coals is irrespective of the coal-forming vegetation.

AB - Biomarker composition and polycyclic aromatic hydrocarbons (PAHs)concentrations of three coal samples from Bulgarian deposits of different rankare presented. The coal samples were taken from Stanyantsi, Bourgas and Dobroudja coal basins. Gas chromatography–mass spectrometry (GC-MS) wasapplied to assess organic matter source and to identify and quantify PAHs inthe studied samples. Coal rank was determined on the basis of vitrinite reflectance, Ro %.The alkane patterns of the three samples are dominated by long chainn-alkanes (C27-C31), usually found in higher terrestrial plants rich in cuticular waxes. With increasing rank, the odd over even predominance is significantly reduced and short-chain n-alkanes are present in higher quantities.Increased pristane/phytane ratios in the Dobroudja coals are attributed to theinfluence of coal rank on this parameter. Based on terpenoid biomarker composition, angiosperm-dominated vegetation is concluded for the Bourgas coalwhereas conifers dominated the peat-forming vegetation at Stanyantsi. Lowterpenoid biomarker concentration and high contents of alkylated naphthalenesand phenanthrenes in the bituminous coal reflect the diagenetic conversion ofthe plant-derived terpenoid hydrocarbons to alkylated PAHs. Highest PAHsconcentration was recorded in samples of higher rank (bituminous coal), and the lowest concentration was found in lignite samples. The examination of thePAHs composition revealed that 3 and 4 ring unsubstituted PAHs are dominant in the lignite and bituminous coal samples, whereas 4 and 5 ring PAHspredominate in subbituminous coal. We assume that the composition of PAHsin the extractable portion of coals is irrespective of the coal-forming vegetation.

M3 - Article

VL - 70.2017

SP - 243

EP - 252

JO - Dokladi na Bălgarskata Akademija na Naukite = Comptes rendus de l'Académie Bulgare des Sciences

JF - Dokladi na Bălgarskata Akademija na Naukite = Comptes rendus de l'Académie Bulgare des Sciences

SN - 1310-1331

IS - 2

ER -