Background

Biomarkers that are incorporated into bitumens or kerogens through covalent bonding can survive intact to relatively high maturity levels thanks to the protection afforded by the macromolecular structure. Thus, covalently bound biomarkers can be used as geochemical indicators over a much broader range than that of their free counterparts. Here, we explore the possibility of catalytic hydrogenation to release covalently bound biomarkers using the Micro-Scale Sealed Vessel system, here named MSSV catalytic hydrogenation. It combines a closed-system pyrolysis with a dispersed sulphidic molybdenum catalyst in the presence of tetralin. Tetralin has been used extensively in coal liquefication as a hydrogen donor. The use of tetralin also suppresses the cross linking reactions of kerogen fragments due to the penetration of tetralin into the micropores. Meanwhile, the use of catalyst will reduce the activation energy of covalent bond cracking. Therefore, catalytic hydrogenation using tetralin can also increase the yields of pyrolysis products.

Goals

The aim of this research is to find the optimal experimental conditions of MSSV catalytic hydrogenation to release covalently bound biomarkers and further use it on the research of covalently bound biomarkers. This involves:

• Establishing the optimal experimental conditions of MSSV catalytic hydrogenation
• Comparing released biomarkers by MSSV catalytic hydrogenation to those by HyPy using samples from China
• Extending the method to study the release of biomarkers from natural maturity sequence 

Participants

• Dr. Wu Liangliang (State Key Laboratory of Org. Geochemistry, China)
• Prof. Brian Horsfield (GFZ)
• Ferdinand Perssen (GFZ)
• Cornelia Karger (GFZ)