Stepwise Chemical Demineralization of Göynük (Turkey) Oil Shale and Pyrolysis of Demineralization Products

In this study, the effect of the mineral matter of Göynük oil shale on the conversion of organic carbon in
kerogen into volatile hydrocarbons, polycyclic aromatic hydrocarbons (asphaltenes, preasphaltenes), and carbon
in the solid residue was investigated. Kerogen was isolated by successive HCl, HNO3, and HF treatments. A
series of temperature-programmed pyrolysis operations was performed with raw Göynük oil shale and each
product of every demineralization process. The results show that removal of the material soluble in HCl and
HNO3 slightly affected the conversion of organic materials in the pyrolysis reactions. In contrast, removal of
the material soluble in HF increased the conversion in pyrolysis reactions. This behavior is explained by the
inhibitive effect of the silicate minerals. The leaching of mineral matter with HCl, HNO3, and HF caused no
remarkable change in the composition of volatile hydrocarbons.