Abstract
Shorter processes and lower temperatures are critical to reducing thermally modified wood costs. In this study, the exogenous H3PO4 was infiltrated into poplar (Populus × euramaricana) and then heated at low temperatures of 130–170 °C to speed up the thermal modification process of wood with better performance. The hygroscopicity was analyzed by dynamic vapor sorption detection and its constituents of modified wood were characterized by high-performance liquid chromatography and solid-state CP/MAS 13C NMR. The results showed that acid combined with low-temperature thermal modification (acid-LTM) resulted in lower equilibrium moisture content compared with the high-temperature thermal modification (HTM) wood. The addition of H3PO4 triggered severe degradation of the carbohydrates in the wood, and the mass loss of cellulose and hemicellulose were 11.9% and 24.1% when modified with 3.0% H3PO4 at 150 °C, respectively, thereby reducing the quantities of water sorption sites. Besides, the degradation products of carbohydrates crosslinked with the thermally stable lignin to form “pseudo-lignin” substances, leading to an increase in the lignin content of acid-LTM wood. The increase in the crystalline index and crystallite size of cellulose in acid-LTM wood was also conducive to reducing the wood hygroscopicity. The better hydrophobicity of acid-LTM poplar was further verified by its decrease in the water sorption site density and the theoretical OH content compared with HTM wood and unmodified wood. This study will offer a potential process to manufacture thermal-modified wood at a low cost.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Akgül M, Gumuskaya E, Korkut S (2007) Crystalline structure of heat-treated Scots pine [Pinus sylvestris L.] and Uludag fir [Abies nordmanniana (Stev.) subsp bornmuelleriana (Mattf.)] wood. Wood Sci Technol 41:281–289. https://doi.org/10.1007/s00226-006-0110-9
Anderson RB, Hall WK (1948) Modifications of the Brunauer, Emmett and Teller equation II. J Am Chem Soc 70:1727–1734. https://doi.org/10.1021/ja01185a017
Bardet M, Gerbaud G, Giffard M, Doan C, Hediger S, Le Pape L (2009) 13C high-resolution solid-state NMR for structural elucidation of archaeological woods. Prog Nucl Mag Res Sp 55:199–214. https://doi.org/10.1016/j.pnmrs.2009.02.001
Bhuiyan MTR, Hirai N, Sobue N (2000) Changes of crystallinity in wood cellulose by heat treatment under dried and moist conditions. J Wood Sci 46:431–436. https://doi.org/10.1007/BF00765800
Broda M, Spear MJ, Curling SF, Dimitriou A (2022) Effects of biological and chemical degradation on the properties of Scots Pine-Part II: wood-moisture relations and viscoelastic behavior. Forests 13:1390. https://doi.org/10.3390/f13091390
Brunauer S, Emmett P, Teller E (1938) Adsorption of gases in multimolecular layers. J Am Chem Soc 60:309–319. https://doi.org/10.1021/ja01269a023
Cai CY, Antikainen J, Luostarinen K, Mononen K, Herajarvi H (2018) Wetting-induced changes on the surface of thermally modified Scots pine and Norway spruce wood. Wood Sci Technol 52:1181–1193. https://doi.org/10.1007/s00226-018-1030-1
Cao YJ (2008) Properties and control theory for strength loss of stream heat-treated Wood. Dissertation, Chinese Academy of Forestry, China
Chen Y, Li G, Yang F, Zhang SM (2011) Mn/ZSM-5 participation in the degradation of cellulose under phosphoric acid media. Polym Degrad Stabil 96:863–869. https://doi.org/10.1016/j.polymdegradstab.2011.02.007
Esteves B, Ayata U, Cruz-Lopes L, Bras I, Ferreira J, Domingos I (2022) Changes in the content and composition of the extractives in thermally modified tropical hardwoods. Maderas-Cienc Tecnol 22:1–14. https://doi.org/10.4067/s0718-221x2022000100422
Fadeeva J, Shmukler L, Safonova L (2003) Investigation of the phosphoric acid -N, N-dimethylformamide system as potential solvent for cellulose. J Mol Liq 103:339–347. https://doi.org/10.1016/S0167-7322(02)00152-6
Ferreira J, Herrera R, Labidi J, Esteves B, Domingos I (2018) Energy and environmental profile comparison of TMT production from two different companies—a Spanish/Portuguese case study. Forest 11:155–161. https://doi.org/10.3832/ifor2339-010
Fredriksson M (2019) On wood–water interactions in the over-hygroscopic moisture range—mechanisms, methods, and influence of wood modification. Forests 10:779. https://doi.org/10.3390/f10090779
Fredriksson M, Thybring EE (2018) Scanning or desorption isotherms? Characterising sorption hysteresis of wood. Cellulose 25:4477–4485. https://doi.org/10.1007/s10570-018-1898-9
Funaoka M, Kako T, Abe I (1990) Condensation of lignin during heating of wood. Wood Sci Technol 24:277–288. https://doi.org/10.1007/BF01153560
Ganne-Chedeville C, Jaaskelainen AS, Froidevaux J, Hughes M, Navi P (2012) Natural and artificial ageing of spruce wood as observed by FTIR-ATR and UVRR spectroscopy. Holzforschung 66:163–170. https://doi.org/10.1515/HF.2011.148
Garcia-Iruela A, Esteban LG, Fernandez FG, de Palacios P, Rodriguez-Navarro AB, Martin-Sampedro R, Eugenio ME (2021) Changes in cell wall components and hygroscopic properties of Pinus radiata caused by heat treatment. Eur J Wood Prod 79:851–861. https://doi.org/10.1007/s00107-021-01678-2
Gérardin P, Petric M, Petrissans M, Lambert J, Ehrhrardt JJ (2007) Evolution of wood surface free energy after heat treatment. Polym Degrad Stabil 92:653–657. https://doi.org/10.1016/j.polymdegradstab.2007.01.016
Ghavidel A, Hosseinpourpia R, Militz H, Vasilache V, Sandu I (2020) Characterization of archaeological european white elm (Ulmus laevis P.) and Black Poplar (Populus nigra L.). Forests 11:1329. https://doi.org/10.3390/f11121329
Guo J, Song KL, Salmen L, Yin YF (2015) Changes of wood cell walls in response to hygro-mechanical steam treatment. Carbohyd Polym 115:207–214. https://doi.org/10.1016/j.carbpol.2014.08.040
Guo J, Zhou HB, Stevanic JS, Dong MY, Yu M, Salmen L, Yin YF (2017) Effects of ageing on the cell wall and its hygroscopicity of wood in ancient timber construction. Wood Sci Technol 52:131–147. https://doi.org/10.1007/s00226-017-0956-z
Hailwood AJ, Horrobin S (1946) Absorption of water by polymers: analysis in terms of a simple model. Trans Faraday Soc 42:B084–B092. https://doi.org/10.1039/TF946420B084
Hakkou M, Pétrissans M, Zoulalian A, Gérardin P (2005) Investigation of the reasons of the increase of wood durability after heat treatment based on changes of wettability and chemical composition. In: The second European conference on wood modification, Göttingen, pp 36–46
He J, Huang CX, Lai CH, Huang C, Li X, Yong Q (2018) Elucidation of structure-inhibition relationship of monosaccharides derived pseudo-lignin in enzymatic hydrolysis. Ind Crop Prod 113:368–375. https://doi.org/10.1016/j.indcrop.2018.01.046
He J (2020) Study on the generation of pseudo lignin and its mechanism on the saccharification of cellulose. Dissertation, Nanjing Forestry University, China
Hill CAS, Ramsay J, Keating B, Laine K, Rautkari L, Hughes M, Constant B (2012) The water vapour sorption properties of thermally modified and densified wood. J Mater Sci 47:3191–3197. https://doi.org/10.1007/s10853-011-6154-8
Hill C, Altgen M, Rautkari L (2021) Thermal modification of wood—a review: chemical changes and hygroscopicity. J Mater Sci 56:6581–6614. https://doi.org/10.1007/s10853-020-05722-z
Hoffmeyer P, Jensen SK, Jones D, Klinke HB, Felby C (2003) Sorption properties of steam treated wood and plant fibres. In: European conference on wood modification. Universiteit Gent, vol 1, pp 177–189
Hosseinpourpia R, Adamopoulos S, Holstein N, Mai C (2017) Dynamic vapour sorption and water-related properties of thermally modified Scots pine (Pinus sylvestris L.) wood pre-treated with proton acid. Polym Degrad Stabil 138:161–168. https://doi.org/10.1016/j.polymdegradstab.2017.03.009
Hou SY, Wang JY, Yin FY, Qi CS, Mu J (2022) Moisture sorption isotherms and hysteresis of cellulose, hemicelluloses and lignin isolated from birch wood and their effects on wood hygroscopicity. Wood Sci Technol 56:1087–1102. https://doi.org/10.1007/s00226-022-01393-y
Hrčka R, Kučerová V, Hýrošová T, Hönig V (2020) Cell wall saturation limit and selected properties of thermally modified Oak wood and cellulose. Forests 11:640. https://doi.org/10.3390/f11060640
Huang XA, Kocaefe D, Kocaefe Y, Boluk Y, Krause C (2013) Structural analysis of heat-treated birch (Betule papyrifera) surface during artificial weathering. Appl Surf Sci 264:117–127. https://doi.org/10.1016/j.apsusc.2012.09.137
Hult EL, Larsson PT, Iversen T (2000) A comparative CP/MAS 13C-NMR study of cellulose structure in spruce wood and kraft pulp. Cellulose 7:35–55. https://doi.org/10.1023/A:1009236932134
Humar M, Repic R, Krzisnik D, Lesar B, Korosec RC, Brischke C, Emmerich L, Rep G (2020) Quality control of thermally modified timber using dynamic vapor sorption (DVS) analysis. Forests 11:666. https://doi.org/10.3390/f11060666
Idstrom A, Schantz S, Sundberg J, Chmelka BF, Gatenholm P, Nordstierna L (2016) 13C NMR assignments of regenerated cellulose from solid-state 2DNMR spectroscopy. Carbohyd Polym 151:480–487. https://doi.org/10.1016/j.carbpol.2016.05.107
Jalaludin Z, Hill CAS, Xie Y, Samsi HW, Husain H, Awang K, Curling SF (2010) Analysis of the water vapour sorption isotherms of thermally modified acacia and sesendok. Wood Mater Sci Eng 5:194–203. https://doi.org/10.1080/17480272.2010.503940
Kohler R, Dück R, Ausperger B, Alex R (2003) A numeric model for the kinetics of water vapor sorption on cellulosic reinforcement fibers. Compos Interface 10:255–276. https://doi.org/10.1163/156855403765826900
Kostryukov SG, Petrov PS, Tezikova VS, Masterova YYU, Idris TJ, Kostryukov NS (2021) Determination of wood composition using soild-state 13C NMR spectroscopy. Cell Chem Technol 55:461–468. https://doi.org/10.35812/cellulosechemtechnol.2021.55.42
Kotilainen RA, Toivanen TJ, Alén RJ (2000) FTIR monitoring of chemical changes in softwood during heating. J Wood Chem Technol 20:307–320. https://doi.org/10.1080/02773810009349638
Kuribayashiet T, Ogawa Y, Morfin I, Matsumoto Y, Nishiyama Y (2023) Mesostructural changes in cellulose within wood cell wall upon hydrothermal treatment at 200 °C. Cellulose 30:8405–8413. https://doi.org/10.1007/s10570-023-05388-1
Kyyrö S, Altgen M, Seppalainen H, Belt T, Rautkari L (2021) Effect of drying on the hydroxyl accessibility and sorption properties of pressurized hot water extracted wood. Wood Sci Technol 55:1203–1220. https://doi.org/10.1007/s00226-021-01307-4
Kyyrö S, Altgen M, Belt T, Seppalainen H, Brischke C, Heinze P, Militz H, Rautkari L (2022) Effect of pressurized hot water extraction and esterification on the moisture properties and decay resistance of Scots pine (Pinus sylvestris L.) sapwood. Holzforschung 76:916–928. https://doi.org/10.1515/hf-2022-0100
Ling Z, Lai CH, Huang CX, Xu F, Yong Q (2021) Research progress in variations of cellulose supramolecular structures via biomass pretreatment. J for Eng 4:24–34. https://doi.org/10.13360/j.issn.2096-1359.202006024
Lionetto F, Del Sole R, Cannoletta D, Vasapollo G, Maffezzoli A (2012) Monitoring wood degradation during weathering by cellulose crystallinity. Materials 5:1910–1922. https://doi.org/10.3390/ma5101910
Luo CM, Wang QH, Wang XJ, Sun ZJ, Qi CS, Mu J (2023) Physical and mechanical characteristics of poplar treated with phosphoric acid under low-temperature thermal modification. Wood Mater Sci Eng 18:1372–1381. https://doi.org/10.1080/17480272.2022.2141657
Niemz P, Teischinger A, Sandberg D (2023) Springer handbook of wood science and technology. Springer, Switzerland. https://doi.org/10.1007/978-3-030-81315-4
Nishiyama Y, Langan P, O’Neill H, Pingali SV, Harton S (2014) Structural coarsening of aspen wood by hydrothermal pretreatment monitored by small- and wide-angle scattering of X-rays and neutrons on oriented specimens. Cellulose 21:1015–1024. https://doi.org/10.1007/s10570-013-0069-2
Nomura S, Kugo Y, Erata T (2020) 13C NMR and XRD studies on the enhancement of cellulose II crystallinity with low concentration NaOH post-treatments. Cellulose 27:3553–3563. https://doi.org/10.1007/s10570-020-03036-6
Oh SY, Yoo DI, Shin Y, Seo G (2005) FTIR analysis of cellulose treated with sodium hydroxide and carbon dioxide. Carbohyd Res 340:417–428. https://doi.org/10.1016/j.carres.2004.11.027
Ozgenc O, Durmaz S, Boyaci IH, Eksi-Kocak H (2017) Determination of chemical changes in heat-treated wood using ATR-FTIR and FT Raman spectrometry. Spectrochim Acta A 171:395–400. https://doi.org/10.1016/j.saa.2016.08.026
Poletto M, Zattera AJ, Santana RMC (2012) Thermal decomposition of wood: kinetics and degradation mechanisms. Bioresource Technol 126:7–12. https://doi.org/10.1016/j.biortech.2012.08.133
Rautkari L, Hill CAS, Curling S, Jalaludin ZH, Ormondroyd G (2013) What is the role of the accessibility of wood hydroxyl groups in controlling moisture content? J Mater Sci 48:6352–6356. https://doi.org/10.1007/s10853-013-7434-2
Rowell RM (1980) Distribution of reacted chemicals in southern pine modified with methyl isocyanate. Wood Sci 13:102–110
Salmen L, Larsson PA (2018) On the origin of sorption hysteresis in cellulosic materials. Carbohyd Polym 182:15–20. https://doi.org/10.1016/j.carbpol.2017.11.005
Sandberg D, Kutnar A, Karlsson O, Jones D (2021) Wood modification technologies, principles, sustainability, and the need for innovation. Boca Raton, London, New York. https://doi.org/10.1201/9781351028226
Segal L, Creely JJ, Martin AE Jr, Conrad CM (1959) An empirical method for estimating the degree of crystallinity of native cellulose using the X-ray diffractometer. Text Res J 29:786–794. https://doi.org/10.1177/0040517559029010
Shen XS, Guo DK, Jiang P, Yang S, Li GY, Chu FX (2021) Water vapor sorption mechanism of furfurylated wood. J Mater Sci 56:11324–11334. https://doi.org/10.1007/s10853-021-06041-7
Siripong P, Duangporn P, Takata E, Tsutsumi Y (2016) Phosphoric acid pretreatment of Achyranthes aspera and Sida acuta weed biomass to improve enzymatic hydrolysis. Bioresource Technol 203:303–308. https://doi.org/10.1016/j.biortech.2015.12.037
Sluiter A, Ruiz R, Scarlata C, Sluiter J, Templeton D (2008) LAP “Determination of extractives in biomass”. National Renewable Energy Laboratory. NREL/TP-510-42619, January 2008
Sluiter A, Hames B, Ruiz R, Scarlata C, Sluiter J, Templeton D, Crocker D (2012) LAP “Determination of structural carbohydrates and lignin in biomass”. National Renewable Energy Laboratory. NREL/TP-510-42618, Revised August 2012
Time B (1998) Hygroscopic moisture transport in wood. Dissertation, Norwegian University of Science and Technology, Norway
Tjeerdsma BF, Militz H (2005) Chemical changes in hydrothermal treated wood: FTIR analysis of combined hydrothermal and dry heat-treated wood. Holz Roh Werkst 63:102–111. https://doi.org/10.1007/s00107-004-0532-8
Uyup MKA, Sahari SH, Jalaludin Z, Husain H, Lee SH, Yusoh AS (2021) Water vapour sorption behaviour and physico-mechanical properties of methyl methacrylate (MMA)- and MMA-styrene-modified batai (Paraserianthes falcataria) wood. Holzforschung 75:444–451. https://doi.org/10.1515/hf-2020-0005
Wang D, Fu F, Lin LY (2022) Molecular-level characterization of changes in the mechanical properties of wood in response to thermal treatment. Cellulose 29:3131–3142. https://doi.org/10.1007/s10570-022-04471-3
Wentzel M, Altgen M, Militz H (2018) Analyzing reversible changes in hygroscopicity of thermally modified eucalypt wood from open and closed reactor systems. Wood Sci Technol 52:889–907. https://doi.org/10.1007/s00226-018-1012-3
Willems W (2014a) Hydrostatic pressure and temperature dependence of wood moisture sorption isotherms. Wood Sci Technol 48:483–498. https://doi.org/10.1007/s00226-014-0616-5
Willems W (2014b) The water vapor sorption mechanism and its hysteresis in wood: the water/void mixture postulate. Wood Sci Technol 48:499–518. https://doi.org/10.1007/s00226-014-0617-4
Willems W (2015) A critical review of the multilayer sorption models and comparison with the sorption site occupancy (SSO) model for wood moisture sorption isotherm analysis. Holzforschung 69:67–75. https://doi.org/10.1515/hf-2014-0069
Windeisen E, Strobel C, Wegener G (2007) Chemical changes during the production of thermo-treated beech wood. Wood Sci Technol 41:523–536. https://doi.org/10.1007/s00226-007-0146-5
Xue BL, Wen JL, Xu F, Sun RC (2012) Structural characterization of hemicelluloses fractionated by graded ethanol precipitation from Pinus yunnanensis. Carbohyd Res 352:159–165. https://doi.org/10.1016/j.carres.2012.02.004
Yuan HM, Tang SY, Luo QY, Xiao T, Wang W, Ma Q, Guo X, Wu YQ (2020) Micro-FTIR spectroscopy and partial least-squares regression for rapid determination of moisture content of nanogram-scaled heat-treated wood. J Wood Sci 66:1. https://doi.org/10.1186/s10086-020-1848-7
Zaihan J, Hill CAS, Curling S, Hashim WS, Hamdan H (2009) Moisture adsorption isotherms of Acacia mangium and Endospermum malaccense using dynamic vapour sorption. J Trop for Sci 21:277–285
Zhou F, Fu ZY, Gao X, Zhou YD (2020) Changes in the wood-water interactions of mahogany wood due to heat treatment. Holzforschung 74:853–863. https://doi.org/10.1515/hf-2019-0192
Zhuang JS, Wang XJ, Xu JY, Wang ZJ, Qin MH (2017) Formation and deposition of pseudo-lignin on liquid-hot-water-treated wood during cooling process. Wood Sci Technol 51:165–174. https://doi.org/10.1007/s00226-016-0872-7
Acknowledgements
This work was financially supported by the National Natural Science Foundation of China (Nos. 31971589 and 31870536) and the National Key Research and Development Program of China (2023YFD2200501).
Author information
Authors and Affiliations
Contributions
CL and CQ contributed to the study's conception and design. CL and SH performed material preparation, data collection, and numerical analyses. JM and CQ supervised and funded the work. CL wrote the main manuscript text and all authors commented on previous versions. All authors reviewed and approved the final manuscript.
Corresponding authors
Ethics declarations
Conflict of interest
The authors declare no competing interests.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary Information
Below is the link to the electronic supplementary material.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Luo, C., Hou, S., Mu, J. et al. How does phosphoric acid affect the hygroscopicity and chemical components of poplar thermally modified at low temperatures?. Wood Sci Technol 58, 699–723 (2024). https://doi.org/10.1007/s00226-024-01543-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00226-024-01543-4