Perspective | Published:

Molecular-level driving forces in lignocellulosic biomass deconstruction for bioenergy

Abstract

The plant cell wall biopolymers lignin, cellulose and hemicellulose are potential renewable sources of clean biofuels and high-value chemicals. However, the complex 3D structure of lignocellulosic biomass is recalcitrant to deconstruction. Major efforts to overcome this recalcitrance have involved pretreating biomass before catalytic processing. This Perspective describes recent work aimed at elucidating the molecular-level physical phenomena that drive biomass assembly. These are at play in commonly employed aqueous-based and thermochemical pretreatments. Several key processes have been found to be driven by biomass solvation thermodynamics, an understanding of which therefore facilitates the rational improvement of methods aimed at the complete solubilization and fractionation of the major biomass components.

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Acknowledgements

This research was supported by the Genomic Science Program, Office of Biological and Environmental Research, US Department of Energy (DOE), under Contract FWP ERKP752. This research used the resources of three user facilities supported by the DOE: the National Energy Research Scientific Computing Center (NERSC; contract no. DE-AC02-05CH11231), High Flux Isotope Reactor/Spallation Neutron Source (HFIR/SNS; DE-AC02-05CH11231) and Oak Ridge Leadership Computing Facility (OLCF; contract no. DE-AC05-00OR22725).

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Correspondence to Jeremy C. Smith.

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Further reading

Fig. 1: The structure of lignocellulosic biomass and its components.
Fig. 2: Molecular dynamics models of three states of lignin
Fig. 3: Steam explosion pretreatment causes cellulose fibrils to coalesce.
Fig. 4: A molecular dynamics snapshot of cellulose in tetrahydrofuran–H2O.