Abstract:
:A particularly promising approach to deconstructing and fractionating lignocellulosic biomass to produce green renewable fuels and high-value chemicals pretreats the biomass with organic solvents in aqueous solution. Here, neutron scattering and molecular-dynamics simulations reveal the temperature-dependent morphological changes in poplar wood biomass during tetrahydrofuran (THF):water pretreatment and provide a mechanism by which the solvent components drive efficient biomass breakdown. Whereas lignin dissociates over a wide temperature range (>25 °C) cellulose disruption occurs only above 150 °C. Neutron scattering with contrast variation provides direct evidence for the formation of THF-rich nanoclusters (Rg ∼ 0.5 nm) on the nonpolar cellulose surfaces and on hydrophobic lignin, and equivalent water-rich nanoclusters on polar cellulose surfaces. The disassembly of the amphiphilic biomass is thus enabled through the local demixing of highly functional cosolvents, THF and water, which preferentially solvate specific biomass surfaces so as to match the local solute polarity. A multiscale description of the efficiency of THF:water pretreatment is provided: matching polarity at the atomic scale prevents lignin aggregation and disrupts cellulose, leading to improvements in deconstruction at the macroscopic scale.
journal_name
Proc Natl Acad Sci U S Aauthors
Pingali SV,Smith MD,Liu SH,Rawal TB,Pu Y,Shah R,Evans BR,Urban VS,Davison BH,Cai CM,Ragauskas AJ,O'Neill HM,Smith JC,Petridis Ldoi
10.1073/pnas.1922883117subject
Has Abstractpub_date
2020-07-21 00:00:00pages
16776-16781issue
29eissn
0027-8424issn
1091-6490pii
1922883117journal_volume
117pub_type
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