Influence of storage on the emission of volatile acids from wood chips

Abstract

Results of investigations on the influence of storage of wood chips from pine (Pinus sylvestris L.) and spruce (Picea abies Karst.) clearly showed that storage decreases the emission of volatile acids (formic and acetic acid). Moreover, it became obvious from the results that huge differences exist between pine and spruce in the emanation of volatile acids. The higher emission of formic acid from pine wood may be due to the much higher extractive content in pine wood compared to spruce as has been shown in a previous publication. Furthermore, the results reveal that thermo-mechanical pulping (TMP) of wood enhances, in general, the release of formic and acetic acid from wood. The release of volatile acids from TMP declines due to storage of wood. Storage also narrows the differences in the emission between pine and spruce wood particles and TMP prepared therefrom. It seems that there is some interrelation between the extractive content of wood and its change during storage on the one side and the release of volatile acids on the other side.