The Effects of Clay Minerals on Methylated Naphthalenes as Maturity Indicators of Sedimentary Organic Matter

We investigated clay-catalyzed thermal isomerization of methylated naphthalenes. Methylated naphthalenes were heated with montmorillonite, kaolinite, sericite, and CaCO3. Immature coal was heated with and without montmorillonite. Our experiments showed that montmorillonite and kaolinite promoted isomerization of methylated naphthalenes. The high protonation ability and large specific surface area of montmorillonite may have controlled the isomerization rate. The results suggest that coexisting clay minerals will affect the maturation of sedimentary organic matter in the natural environment.