Mechanisms of Terpene Release During Sawdust and Flake Drying

Abstract

Summary The water and α-pinene released during sawdust and flake drying were simultaneously measured. For sawdust, the drying profiles for water and pinene are very different at oven temperatures of 105 °C, but are similar at 200 °C. There is an initial burst of pinene very early in the process, which is mainly attributed to the loss of pinene dissolved in surface water. Later, the pinene and water are released in a nearconstant ratio, which is ascribed to water mobilizing pinene from the interior of the wood matrix to the wet line. The surfactants present in wood are believed to solubilize pinene into water. Finally, pinene is lost through evaporation when the wood is almost dry. Hence, at least three mechanisms are operative for the movement and release of α-pinene and other terpenes from wood.