Searching for optimal measurement parameters by thermogravimetry for determining the degree of modification of thermally modified wood

Cerc Korošec, Romana (author), Žener, Boštjan (author), Čelan Korošin, Nataša (author), Humar, Miha (author), Kržišnik, Davor (author), Rep, Gregor (author), Lavrenčič Štangar, Urška (author)

When wood is thermally modified, several chemical reactions take place that change the chemical and physical properties of the wood. These changes correlate with the degree of modification, which is mostly a function of the temperature and duration of modification, and consequently with the mass loss during this process. There is a lack of standardised quality control to verify the degree of heat treatment of wood and thus its quality. One of the possible methods to check the degree of thermal modification of a particular type of wood is thermogravimetry (TG). It is based on the assumption that processes that did not take place during thermal modification continue when the TG experiment is carried out. In this method, calibration curves have to be established based on TG measurements of standard samples that have been thermally modified at different temperatures and whose mass loss during modification is known. The calibration curves show the mass loss during the TG measurement as a function of the mass loss during the previous thermal modification. The course of thermal decomposition during the TG measurements is influenced by many parameters, such as the mass of the sample, the heating rate, the atmosphere in which the measurement takes place, and the shape of the crucible in which the sample is placed. In this paper, the influence of these parameters on the calibration curves was investigated. We have focused on oak wood. The best parameters result in a calibration curve with the largest correlation coefficient $R^2$ and the highest slope of the line k. On this basis, we can determine the mass loss during the thermal modification of unknown samples of the same wood species under the same measurement conditions.

• Language: English
• Keywords: thermal treatment, wood modification, thermogravimetry, calibration curve, quality control
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology; BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Publication date: 01.01.2024
• Year: 2024
• Number of pages: 15 str.
• Numbering: Vol. 15, iss. 1, art. 8
• PID: 20.500.12556/RUL-153347
• UDC: 630*84:543.573
• ISSN on article: 1999-4907
• DOI: 10.3390/f15010008
• COBISS.SI-ID: 178666755
• Publication date in RUL: 22.12.2023

Record is a part of a journal

• Title: Forests
• Shortened title: Forests
• Publisher: MDPI
• ISSN: 1999-4907
• COBISS.SI-ID: 3872166

Licences

• License: CC BY-NC 4.0, Creative Commons Attribution-NonCommercial 4.0 International
• Link: http://creativecommons.org/licenses/by-nc/4.0/
• Description: A creative commons license that bans commercial use, but the users don’t have to license their derivative works on the same terms.

Secondary language

• Language: Slovenian
• Keywords: termična obdelava, modifikacija lesa, termogravimetrija, kalibracijska krivulja, nadzor kakovosti

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P1-0134
• Name: Kemija za trajnostni razvoj

• Funder: ARRS - Slovenian Research Agency
• Project number: P4-0015
• Name: Les in lignocelulozni kompoziti