Transformations of n -alkanes from petroleum pollutants in alluvial groundwaters

Abstract

Investigations presented in this paper were aimed at defining the alterations of n-alkane composition in cases of oil-polluted alluvial sediments. Therefore, oil-polluted groundwater samples, taken in five different time intervals during a period of 28 months, were investigated. Samples of alluvial sediments were taken from two boreholes within an oil refinery at Pancevo, Yugoslavia. In both boreholes significant alterations with characteristic degradation of "oil" n-alkanes with no odd-or even-member predominance were observed, as well as subsequent synthesis of new ones with pronounced even-member predominance, and with maxima at C 16 and C 18 . Since no additional contamination of boreholes was observed by analyses of steranes and triterpanes, the observed changes can only be attributed to microbial activity. It is assumed that for the degradation of oil n-alkanes, as well as for the synthesis of "new" n-alkanes, algae such as dinoflagellates are responsible. This assumption was confirmed by identification of n-alcohols with even-member predominance (C 14 -C 20 ), by identification of cholesterol, as well as of n-fatty acids with even-member predominance (C 14 -C 18 ) in the extract with n-alkane even-member predominance.

Investigation of bioremediation potential of zymogenous bacteria and fungi for crude oil degradation

“…n-Alkanes were identified from m/z 71 fragmentograms. Detailed descriptions of analytical procedure and applied analytical techniques were discussed in our previous papers (e.g., Jovančićević et al 2003;.…”

Salt Marsh Bacterial Communities before and after the Deepwater Horizon Oil Spill

“…Therefore, although total n-alkane concentrations were determined by summing all measured compounds from the marsh sediment samples (nC 10 to nC 35 ), distinction among the different size and size ranges of n-alkanes was also done because specific NOM sources are linked to these sizes and size ranges. For example, nC 14 to nC 20 can be attributed to microbial biosynthesis (122,123). For marine phytoplankton (including phototrophic and nonphototrophic bacteria), nC 17 is the dominant homologue, whereas nC 15 or nC 17 are the dominant homologues for algae, and zooplankton have bimodal nC 18 and nC 24 peak dominance (122,124,125).…”

Main Types of Organic Matter in Geosphere

“…Typical oil sterane and triterpane distributions in the groundwater sample with n-alkanes not typical for oil fractions (even-numbered homologues predominance, CPI < 1) and in the sample with degraded n-alkanes, are evidence of the presence of oil-type pollution (see figure, Jovančićević et al 2001Jovančićević et al , 2003. Identification of marked sterane and terpane peaks will be given in Tables 2.5 and 2.6).…”