Thermo Sanace

Ostrava, Czech Republic

Thermo Sanace

Ostrava, Czech Republic

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Kacik F.,Technical University In Zvolen | Smira P.,Thermo Sanace | Kacikova D.,Technical University In Zvolen | Reinprecht L.,Technical University In Zvolen | Nasswettrova A.,Thermo Sanace
Cellulose Chemistry and Technology | Year: 2014

Wood is a biological material and changes in its molecular structure during exposures usually have a negative influence on its strength and other mechanical and physical properties. In this work, wet chemical and physico-chemical methods have been used to determine the changes in the cellulose, hemicelluloses, lignin and extractives of the 108 to 390-year-old visually undamaged fir wood taken from beams situated in the Rychvald castle in Czech Republic. Natural ageing of the fir wood without activity of biological agents caused a significant increase of the extractives content (twofold, or for the oldest beam, even fourfold) and a decrease of the hemicelluloses (by maximum 24%), while the amounts of lignin and holocellulose were quite stable (decreased only by 4%). The molecular weights, respectively, degrees of polymerization, were stable in cellulose, decreased in hemicelluloses, while in lignin increased due to condensation reactions.


Kacik F.,Technical University In Zvolen | Vel'Kova V.,Technical University In Zvolen | Smira P.,Thermo Sanace | Nasswettrova A.,Thermo Sanace | And 2 more authors.
Molecules | Year: 2012

Building structures made from fir wood are often attacked by wood-destroying insects for which the terpenes it contains serve as attractants. One of the possibilities for extending the lifetime of structures is to use older wood with a lower content of terpenes and/or thermally modified wood. The study evaluated the levels of terpenes in naturally aged fir wood (108, 146, 279, 287 and 390 years) and their decrease by thermal treatment (the temperature of 60 °C and 120 °C, treatment duration of 10 h). Terpenes were extracted from wood samples by hexane and analyzed by gas-chromatography mass-spectrometry (GC-MS). The results indicate that recent fir wood contained approximately 60 times more terpenes than the oldest wood (186:3.1 mg/kg). The thermal wood treatment speeded up the release of terpenes. The temperature of 60 °C caused a loss in terpenes in the recent fir wood by 62%, the temperature of 120 °C even by >99%. After the treatment at the temperature of 60 °C the recent fir wood had approximately the same quantity of terpenes as non-thermally treated 108 year old wood, i.e., approximately 60-70 mg/kg. After the thermal treatment at the temperature of 120 °C the quantity of terpenes dropped in the recent as well as the old fir wood to minimum quantities (0.7-1.1 mg/kg). The thermal treatment can thus be used as a suitable method for the protection of fir wood from wood-destroying insects.


Kacik F.,Technical University In Zvolen | Luptakova J.,Technical University In Zvolen | Smira P.,Thermo Sanace | Nasswettrova A.,Thermo Sanace | And 2 more authors.
BioResources | Year: 2016

This study investigated alterations in the lignin of pinewood (Pinus sylvestris L.) during heat sterilization. The Klason lignin content was determined, and the dioxane lignin was isolated. Changes in the dioxane lignin were evaluated by size exclusion chromatography (SEC) as well as Fourier transform infrared (FTIR) spectroscopy. The analyses illustrated an increase in the percentage of extractives and the amount of dioxane lignin yields, while a decrease in the acid-insoluble lignin content was also observed. Changes in the macromolecular characteristics of the dioxane lignin (molecular weight and polydispersity) were not significant (p < 0.05); however, they indicated that simultaneous degradation and condensation reactions had occurred. The FTIR spectra of the dioxane lignins showed an increase at 3420 cm-1 (O-H stretching vibration), indicating the cleavage of ether bonds. The band at 1715 cm-1 (unconjugated C=O stretching) increased after an initial decrease due to the cleavage of the β-alkyl-aryl ether bonds. Also, the band at 1660 cm-1 (conjugated C=O groups) increased, which was caused by the cleavage of the α-alkyl-aryl ether bonds.


Kacik F.,Technical University In Zvolen | Smira P.,Thermo Sanace | Kacikova D.,Technical University In Zvolen | Vel'kova V.,Technical University In Zvolen | And 2 more authors.
Carbohydrate Polymers | Year: 2015

Alterations in saccharides during heat sterilisation of pine wood (Pinus sylvestris L.) were investigated. The mass loss, extractives, lignin, cellulose, holocellulose and hemicelluloses were determined. Changes in saccharides were evaluated by the determination of monosaccharides in wood, size exclusion chromatography (SEC) as well as Fourier transform infrared (FTIR) spectroscopy. During heat sterilisation of pine wood the slight mass loss, an increase in extractives and a decrease in lignin and polysaccharides were observed. Hemicelluloses are degraded approximately twice as fast as cellulose. The degree of polymerisation of cellulose decreases approximately by 10% and it increases in holocellulose (by approx. 8%) as a result of a faster degradation of shorter hemicellulose chains. FTIR spectroscopy shows that sterilisation results in the deacetylation of cellulose and the formation of new carbonyl groups, an increase in the total crystallinity index (TCI) and a decrease in the lateral order index (LOI) and the hydrogen-bond intensity (HBI). © 2014 Elsevier Ltd. All rights reserved.


PubMed | Thermo Sanace and Technical University In Zvolen
Type: | Journal: Carbohydrate polymers | Year: 2014

Alterations in saccharides during heat sterilisation of pine wood (Pinus sylvestris L.) were investigated. The mass loss, extractives, lignin, cellulose, holocellulose and hemicelluloses were determined. Changes in saccharides were evaluated by the determination of monosaccharides in wood, size exclusion chromatography (SEC) as well as Fourier transform infrared (FTIR) spectroscopy. During heat sterilisation of pine wood the slight mass loss, an increase in extractives and a decrease in lignin and polysaccharides were observed. Hemicelluloses are degraded approximately twice as fast as cellulose. The degree of polymerisation of cellulose decreases approximately by 10% and it increases in holocellulose (by approx. 8%) as a result of a faster degradation of shorter hemicellulose chains. FTIR spectroscopy shows that sterilisation results in the deacetylation of cellulose and the formation of new carbonyl groups, an increase in the total crystallinity index (TCI) and a decrease in the lateral order index (LOI) and the hydrogen-bond intensity (HBI).

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