Effects of impregnation combined heat treatment on the pyrolysis behavior of poplar wood

Abstract

To investigate the effects of urea-formaldehyde (UF) resin impregnation combined heat treatment (IMPG-HT) on the pyrolysis behavior of poplar wood, the chemical composition, pyrolysis characteristics, pyrolysis kinetics, and gaseous products released during pyrolysis of untreated (control), IMPG-HT, IMPG and HT woods were analyzed. The results demonstrate that IMPG-HT changes pyrolysis behavior of poplar wood significantly. Unlike the control and HT samples, the thermogravimetric / derivative thermogravimetric (TG/DTG) curves of IMPG wood shift toward lower temperature, and the shoulder on DTG curves weaken or even disappear. The maximum mass loss rate of IMPG-HT samples decreases, and carbon residual yield increases to 23% or more and activation energy (E) increases sharply after conversion rate (α) reaching 0.80. HT improves the thermal stability of IMPG wood, which is represented by the increase of decomposition temperature (T d ) and DTG peak temperature (T peak ) and the higher E value of IMPG-HT wood. For the pyrolysis gaseous products, IMPG-HT wood produces nitrogen-containing gases (HNCO and NH 3 ) due to the presence of UF resin, but the amounts of these gases are less than that produced by IMPG wood because the heat treatment had removed part of N elements. (2020) Effects of impregnation combined heat treatment on the pyrolysis behavior of poplar wood. PLoS ONE 15(3): e0229907. https://doi.org/ 10.Effects of impregnation combined heat treatment on the pyrolysis behavior of poplar wood PLOS ONE | https://doi.org/10.1371/journal.pone.0229907 March 17, 2020 2 / 15 Fig 5. The linear fitting diagrams of IMPG-HT samples. (a) The linear fitting diagrams of IMPG-HT samples obtained by FWO method within the conversion range of 0.10<α<0.90; (b) The linear fitting diagrams of IMPG-HT samples obtained by KAS method within the conversion range of 0.10<α<0.90.

Understanding the effect of combined thermal treatment and phenol–formaldehyde resin impregnation on the compressive stress of wood

“…Prominent bands at 1028 cm -1 and 1270 cm -1 arise from the C-O stretch vibration in cellulose, hemicellulose and PF resin. The decrease of these peaks could be due to a chemical reaction between wood and PF resin, which agrees with the findings of Wang et al (2016) and Wu et al (2020). This is possibly because of non-cured PF resin at 103℃, and it is cured and partially decomposed during thermal treatment (200℃).…”

“…All of these are able to induce, to a different extent, changes in the wood properties (Lee et al 2018). Combining thermal modification with functional emulsion impregnation has been an interesting topic to improve the physical and mechanical properties of wood (Awoyemi and Westermark 2005;Salman et al 2016;Taghiyari et al 2020;Wu et al 2020).…”

Effects of different heat treatment media on odorous constituents, chemical decomposition and mechanical properties of two hardwoods

“…Wavelengths 1442 cm −1 and 3300 cm −1 to 3700 cm −1 correspond to the emission of water (H 2 O) in gaseous form, 19,27 while wavelength 2181 cm −1 corresponds to the emission of carbon monoxide (CO) in gaseous form. 28 When Afrormosia and Newtonia wood are heat-treated with palm oil, the most visible peaks are generally located at wavelengths 1050 cm −1 , 1442 cm −1 , 2181 cm −1 and 3300 cm −1 to 3700 cm −1 (Fig. 9 column 1 and Fig.…”