Effects of ultrasonic pretreatment on the drying characteristics of Eucalyptus grandis × Eucalyptus urophylla
In this paper, wood pretreatments were carried out at an ultrasound intensity of 300 W and a frequency of 40 kHz for 60 min, and the ensuing drying process used a temperature of 60 °C. The study analyzed the pretreated wood before and after ultrasonic pretreatment via drying dynamics, electron microscope scanning, and Fourier transform infrared spectroscopy. The results showed that ultrasonic pretreatment successfully improved the effective water diffusivity, decrease the drying time, reduce the amount of extractives on the inner wood pores, and create microchannels in the wood, resulting in improved heat and mass transfer rates. These results indicate that ultrasonic pretreatment is an effective method for the drying of eucalyptus.