Abstract
A fundamental understanding of lignin solubilization offers structural information that would benefit a variety of value added applications. Small angle neutron scattering (SANS) and nuclear magnetic resonance (NMR) spectroscopy were used to study correlations between the functional groups/substructures and solution structures of lignin in DMSO-d6 and 0.1 N NaOD. Three types of alkaline lignins (Sigma-Aldrich kraft lignin, poplar wood kraft lignin, and corncob soda lignin), exhibiting different degrees of aggregation in 0.4 wt% solutions, were investigated to identify the major intermolecular interactions that cause lignin aggregation. Intermolecular hydrogen bonding, non-covalent π-π interactions between phenyl rings, lignin chain conformation and the degree of branching were discussed. Different operating forces for lignin solubilization and aggregation were found in DMSO-d6 and NaOD solutions.
| Original language | English |
|---|---|
| Pages (from-to) | 3272-3281 |
| Number of pages | 10 |
| Journal | Green Chemistry |
| Volume | 19 |
| Issue number | 14 |
| DOIs | |
| State | Published - 2017 |
Bibliographical note
Publisher Copyright:© 2017 The Royal Society of Chemistry.
Funding
Gang Cheng acknowledges support for this research by the National Natural Science Foundation of China (U1432109) and the China Scholarship Council (201606885004). Ling-Ping Xiao thanks the State Key Laboratory of Pulp and Paper Engineering (No. 201518), Open Funding Project of Jiangsu Key Lab of Biomass-based Green Fuels and Chemicals (No. JSBGFC14009), the National Natural Science Foundation of China (No. 21506013), and the China Postdoctoral Science Foundation (No. 2015 M570040). We thank Dr Boualem Hammouda (NCNR, NIST) for his discretionary SANS time and help with the SANS experiment. We acknowledge support from the DOE Joint BioEnergy Institute (http://www.jbei.org) through the U. S. Department of Energy, Office of Science, Office of Biological and Environmental Research, through contract DE-AC02-05CH11231 between Lawrence Berkeley National Laboratory and the U. S. Department of Energy. A portion of this research used resources at the High Flux Isotope Reactor, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. Access to NGB30 SANS was provided by the Center for High Resolution Neutron Scattering, a partnership between the National Institute of Standards and Technology and the National Science Foundation under Agreement No. DMR-1508249. We acknowledge the support from the National Institute of Standards and Technology, U.S. Department of Commerce, in providing the neutron research facilities used in this work. The identification of commercial products does not imply endorsement by the National Institute of Standards and Technology (NIST) nor does it imply that these are the best for the purpose.
| Funders | Funder number |
|---|---|
| Dr Boualem Hammouda | |
| National Science Foundation | DMR-1508249 |
| U.S. Department of Energy | |
| National Institute of Standards and Technology | |
| U.S. Department of Commerce | |
| Office of Science | |
| Biological and Environmental Research | DE-AC02-05CH11231 |
| Oak Ridge National Laboratory | |
| Lawrence Berkeley National Laboratory | |
| NIST Center for Neutron Research | |
| National Natural Science Foundation of China | U1432109 |
| China Postdoctoral Science Foundation | 2015 M570040 |
| China Scholarship Council | 201606885004 |
| State Key Laboratory of Pulp and Paper Engineering | 201518, 21506013, JSBGFC14009 |