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Original Article | Open Access

Structural Changes of Wheat Straw Lignin during Formic Acid Treatment

RuiXue Dong1XiuWen Mei1Chang Ma1MingFei Li2YongMing Fan1( )
MOE Engineering Research Center of Forestry, Biomass Materials, and Bioenergy, Beijing Forestry University, Beijing, 100083, China
Beijing Key Laboratory of Lignocellulosic Chemistry, Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083, China
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The aromatic nature of lignin makes it a potential renewable source of chemicals and other valuable products. Isolation of lignin from lignocellulosic biomass using organic solvents enables the production of high-purity lignin. The use of formic acid in the organosolv pulping and fractionation process has been widely studied. Characterization of lignin is necessary to achieve valueadded applications of lignin. To simplify the isolation of formic acid-treated lignin, herein, milled wheat straw lignin (MWSL) was employed as an archetype for characterization of the structural changes of lignin during formic acid treatment. The results showed that the MWSL was GSH-type (comprising p-hydroxyphenyl (H), guaiacyl (G), and syringyl (S) monolignols) and underwent structural changes during formic acid treatment. Lignin was esterified during the formic acid treatment. The content of alkyl hydroxyl groups in lignin decreased upon formic acid treatment, corresponding to an increase of the number of double bond equivalents (DBE). Lignin units with active reaction sites were liable to slight condensation, which resulted in a moderate increase of the molecular weight. The molecular weight distribution of formic acid-treated MWSL (FMWSL) was wider than that of the MWSL, although the molecular weight of both species did not differ significantly. The β-O-4 linkage in lignin was partially cleaved during formic acid treatment, resulting in the production of new phenolic structures. This improved the solubility of lignin in the cooking liquor and its reactivity for downstream applications.



Buranov A U, Mazza G. Lignin in straw of herbaceous crops[J]. Industrial Crops and Products, 2008, 28(3): 237-259.


Monteil-Rivera F, Phuong M, Ye M, et al. Isolation and characterization of herbaceous lignins for applications in biomaterials[J]. Industrial Crops and Products, 2013, 41(1): 356-364.


Dapτá S, Santos V, ParajóJ C. Study of formic acid as an agent for biomass fractionation[J]. Biomass and Bioenergy, 2002, 22(3): 213-221.


Ligero P, Villaverde J J, de Vega A, et al. Delignification of Eucalyptus globulus saplings in two organosolv systems (formic and acetic acid): Preliminary analysis of dissolved lignins[J]. Industrial Crops and Products, 2008, 27(1): 110-117.


Jahan M S, Chowdhury D A N, Islam M K. Atmospheric formic acid pulping and TCF bleaching of dhaincha (Sesbania aculeata), kash (Saccharum spontaneum) and banana stem (Musa Cavendish)[J]. Industrial Crops and Products, 2007, 26(3): 324-331.


Vanderghem C, Richel A, Jacquet N, et al. Impact of formic/acetic acid and ammonia pre-treatments on chemical structure and physico-chemical properties of Miscanthus x giganteus lignins[J]. Polymer Degradation and Stability, 2011, 96(10): 1761-1770.


Villaverde J J, Ligero P, de Vega A. Formic and acetic acid as agents for a cleaner fractionation of Miscanthus x giganteus[J]. Journal of Cleaner Production, 2010, 18(4): 395-401.


Ghaffar S H, Fan M. Structural analysis for lignin characteristics in biomass straw[J]. Biomass and Bioenergy, 2013, 57: 264-279.

Dence C W, Lin S Y. General structural features of lignin[M]//Methods in Lignin Chemistry. Berlin, Springer-Verlag, 1992: 1-7.

Azadi P, Inderwildi O R, Farnood R, et al. Liquid fuels, hydrogen and chemicals from lignin: A critical review[J]. Renewable and Sustainable Energy Reviews, 2013, 21: 506-523.


Chuck C J, Parker H J, Jenkins R W, et al. Renewable biofuel additives from the ozonolysis of lignin[J]. Bioresource Technology, 2013, 143: 549-554.


Hussin M H, Rahim A A, Ibrahim M N M, et al. Investigation on the structure and antioxidant properties of modified lignin obtained by different combinative processes of oil palm fronds (OPF) biomass[J]. Industrial Crops and Products, 2014, 52: 544-551.


Mahmood N, Yuan Z, Schmidt J, et al. Depolymerization of lignins and their applications for the preparation of polyols and rigid polyurethane foams: A review[J]. Renewable and Sustainable Energy Reviews, 2016, 60: 317-329.


Pempkowiak J, Tylmann W, Staniszewski A, et al. Lignin depolymerization products as biomarkers of the organic matter sedimentary record in 210Pb-137Cs-dated lake sediments[J]. Organic Geochemistry, 2006, 37(11): 1452-1464.


Custodis V B F, Bährle C, Vogel F, et al. Phenols and aromatics from fast pyrolysis of variously prepared lignins from hard- and softwoods[J]. Journal of Analytical and Applied Pyrolysis, 2015, 115: 214-223.


Mante O D, Rodriguez J A, Babu S P. Selective defunctionalization by TiO2 of monomeric phenolics from lignin pyrolysis into simple phenols[J]. Bioresource Technology, 2013, 148: 508-516.


Singh R, Prakash A, Dhiman S K, et al. Hydrothermal conversion of lignin to substituted phenols and aromatic ethers[J]. Bioresource Technology, 2014, 165: 319-322.


Zakzeski J, Bruijnincx P C A, Jongerius A L, et al. The catalytic valorization of lignin for the production of renewable chemicals[J]. Chemical Reviews, 2010, 110(6): 3552-3599.


Foyer G, Chanfi B H, Boutevin B, et al. New method for the synthesis of formaldehyde-free phenolic resins from lignin-based aldehyde precursors[J]. European Polymer Journal, 2016, 74: 296-309.


Cateto C A, Barreiro M F, Rodrigues A E, et al. Kinetic study of the formation of lignin-based polyurethanes in bulk[J]. Reactive and Functional Polymers, 2011, 71(8): 863-869.


Silva E A B D, Zabkova M, Araújo J D, et al. An integrated process to produce vanillin and lignin-based polyurethanes from kraft lignin[J]. Chemical Engineering Research and Design, 2009, 87(9): 1276-1292.


Asada C, Basnet S, Otsuka M, et al. Epoxy resin synthesis using low molecular weight lignin separated from various lignocellulosic materials[J]. International Journal of Biological Macromolecules, 2015, 74: 413-419.


Ferdosian F, Yuan Z, Anderson M, et al. Sustainable lignin-based epoxy resins cured with aromatic and aliphatic amine curing agents: Curing kinetics and thermal properties[J]. Thermochimica Acta, 2015, 618: 48-55.


Sasaki C, Wanaka M, Takagi H, et al. Evaluation of epoxy resins synthesized from steam-exploded bamboo lignin[J]. Industrial Crops and Products, 2013, 43: 757-761.


Kadla J F, Kubo S, Venditti R A, et al. Lignin-based carbon fibers for composite fiber applications[J]. Carbon, 2002, 40(15): 2913-2920.


Ding R, Wu H, Thunga M, et al. Processing and characterization of low-cost electrospun carbon fibers from organosolv lignin/polyacrylonitrile blends[J]. Carbon, 2016, 100: 126-136.


Vishtal A G, Kraslawski A. Challenges in industrial applications of technical lignins[J]. BioResources, 2011, 6(3): 3547-3568.


Huijgen W J J, Telysheva G, Arshanitsa A, et al. Characteristics of wheat straw lignins from ethanol-based organosolv treatment[J]. Industrial Crops and Products, 2014, 59: 85-95.


Dapía S, Santos V, ParajóJ C. Formic acid-peroxyformic acid pulping of Fagus sylvatica[J]. Journal of Wood Chemistry and Technology, 2000, 20(4): 395-413.


Delmas G H, Benjelloun M B, Bigot Y L, et al. Functionality of wheat straw lignin extracted in organic acid media[J]. Journal of Applied Polymer Science, 2011, 121(1): 491-501.


Björkman A. Studies on finely divided wood. Part 1. Extraction of lignin with neutral solvents[J]. Svensk Papperstidning, 1956, 59(13): 477-485.


Glasser W G, Jain R K. Lignin derivatives. I. Alkanoates[J]. Holzforschung, 1993, 47(3): 225-233.


Ibrahim M N M, Zakaria N, Sipaut C S, et al. Chemical and thermal properties of lignins from oil palm biomass as a substitute for phenol in a phenol formaldehyde resin production[J]. Carbohydrate Polymers, 2011, 86(1): 112-119.

Paper and Biomaterials
Pages 16-22
Cite this article:
Dong R, Mei X, Ma C, et al. Structural Changes of Wheat Straw Lignin during Formic Acid Treatment. Paper and Biomaterials, 2016, 1(2): 16-22.










Received: 17 February 2016
Accepted: 05 April 2016
Published: 25 October 2016
© 2016 Published by Paper and Biomaterials Editorial Board

This is an open access article under the CC BY-NC-ND license (