Liquid-saturated hydrocarbons resulting from pyrolysis of the marine coccolithophores Emiliania huxleyi and Gephyrocapsa oceanica

Two nanoplanktonic marine coccolithophores, Emiliania huxleyi and Gephyroca psa oceanica, were grown at 23 degrees C with a 16-hour light and 8-hour da rkness regimen. The cells were dried at room temperature and then subjected to pyrolysis at 100 degrees to 500 degrees C under anoxygenic conditions t o produce hydrocarbons. Temperature-dependent profiles of the liquid-satura ted hydrocarbons (saturates) produced during pyrolysis were very similar fo r the two strains, although the total amount was higher in E. huxleyi than in G. oceanica. The amount of saturates produced was only 0.05% to 0.15% be low 200 degrees C, but about 2.1% to 2.8% at 300 degrees C. Their major com ponents were normal alkanes in a series ranging from nC(11) to nC(35) with the predominant peak at nC(15). At 400 degrees and 500 degrees C most of sa turates transformed into gaseous compounds. The major saturates identified in all pyrolysates were normal C-31 monounsaturated and diunsaturated alken es, a series of normal alkanes. phytenes, C-28 sterenes, and steranes. Prof iles of saturates in gas chromatography-mass spectroscopy varied with incre asing pyrolysis temperature and also differed between E. huxleyi and G. oce anica. The two coccolithophores are useful candidates for the production of renewable liquid fuel through pyrolysis-especially E. huxleyi. which has h igher production. The results also provide information for further studies on the characterization, source, and paleogeographic distribution of marine sediment.