Organic matter structural changes during catagenesis : implications of kerogen chemical structure on petroleum yield and composition.

This work describes the machining of cost-efficient hydrous pyrolysis reactors and furnaces used to simulate natural oil forming (catagenesis) processes. These reactors were used to generate petroleum products from both geologic sediments and biofuel feedstocks, including black shales, coal, algae, and biosolids. Using solid-state 13C NMR spectroscopy, structural changes of the feedstocks and petroleum products were analyzed providing deeper insight into the poorly understood chemistry of oil formation and controls on petroleum composition. A unique comparison between the chemical changes of fresh algae and preserved algae in black shales during catagenesis, elucidated structural changes of organic matter during preservation and differences between biofuel feedstocks and geologic sediments during catagenesis. Additionally, this work resulted in methods for predicting maximum oil yield generation from parent kerogen. Finally, this work demonstrated that both organic matter composition as well as the surrounding chemical environment, for example minerals, are important controls in catagenesis.