Journal Articles Chemical Science Year : 2017

From cellulose to kerogen: molecular simulation of a geological process

Abstract

The process by which organic matter decomposes deep underground to form petroleum and its underlying kerogen matrix has so far remained a no man's land to theoreticians, largely because of the geological (Myears) timescale associated with the process. Using reactive molecular dynamics and an accelerated simulation framework, the replica exchange molecular dynamics method, we simulate the full transformation of cellulose into kerogen and its associated fluid phase under prevailing geological conditions. We observe in sequence the fragmentation of the cellulose crystal and production of water, the development of an unsaturated aliphatic macromolecular phase and its aromatization. The composition of the solid residue along the maturation pathway strictly follows what is observed for natural type III kerogen and for artificially matured samples under confined conditions. After expulsion of the fluid phase, the obtained microporous kerogen possesses the structure, texture, density, porosity and stiffness observed for mature type III kerogen and a microporous carbon obtained by saccharose pyrolysis at low temperature. As expected for this variety of precursor, the main resulting hydrocarbon is methane. The present work thus demonstrates that molecular simulations can now be used to assess, almost quantitatively, such complex chemical processes as petrogenesis in fossil reservoirs and, more generally, the possible conversion of any natural product into bio-sourced materials and/or fuel.
Fichier principal
Vignette du fichier
c7sc03466k.pdf (912.51 Ko) Télécharger le fichier
Origin Publisher files allowed on an open archive
Loading...

Dates and versions

hal-01724050 , version 1 (11-05-2018)

Identifiers

Cite

Lea Atmani, Christophe Bichara, Roland J.-M. Pellenq, Henri van Damme, Adri van Duin, et al.. From cellulose to kerogen: molecular simulation of a geological process. Chemical Science, 2017, 8 (12), pp.8325 - 8335. ⟨10.1039/C7SC03466K⟩. ⟨hal-01724050⟩
489 View
103 Download

Altmetric

Share

More