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The aim of the study was to analyze the kinetic parameters (activation energy Ea, pre-exponential coefficient A, rate constant k) of thermolysis in torrefied and raw willow wood (Salix viminalis L.), as well as to determine the effect of thermal modification conditions on the kinetics of this process. Samples of raw and torrefied willow wood in a steam atmosphere were analysed. The samples were subjected to thermogravimetric analysis under isothermal conditions. Analyses were conducted in an atmosphere of helium at 270–330°C. TG and DTG curves were recorded. The thermal characteristics of the samples were based on thermogravimetric analysis under dynamic conditions at a temperature of up to 600°C. On the basis of the data obtained from the TGA analyses, the kinetic parameters were calculated and statistical and mathematical analyses of the results were performed.
In the article the results are shown of a thermogravimetric analysis of four thermally modified wood species. Thermally modified wood before and after the extraction process was used for the tests. The extraction process had no significant effect on changes in the thermal characteristics either in the raw wood or in the modified wood, irrespective of the tested wood species.
An analysis of thermal decomposition in oxidative conditions of model wood-based materials glued with amino resin. The presented work includes the results of thermal analysis of model samples of particleboards glued with urea-formaldehyde resin with varying degree of sealing (5 ÷ 30%), which is a measurable factor changing the elemental nitrogen content in the samples. Changes of the kinetic parameters of the thermo-destruction reactions occurring in the air were observed as well.
In this work the optimum resination rate of white mustard straw particles with UF resin in the production of straw particleboards was investigated. The resination rates used in this study were 10, 12 and 14%. For the selected resination rate, the possibility of reducing the density of the straw particleboards was also determined. In order to evaluate the hygienic parameters of the experimental boards, the formaldehyde content and volatile organic compounds (VOC) were determined. Moreover, using a thermogravimetric analysis (TGA) the boards’ disposal options by means of burning or co-incineration were investigated. The study results showed thata 10% resination rate enabled the production of white mustard particleboards of type P1 and P2, while the simultaneous reduction in their density to 600 kg/m3limited their application to dry conditions only, i.e. boards of P1 type. Thermogravimetric analysis revealed a variable thermal performance of the studied boards.The pine particleboards showed a higher thermal resistance, however, up to a temperature of 750°C, the samples of the experimental boards underwent a similar process of thermal destruction.
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