Feasibility of incorporating thermally treated lignocellulosic waste in particleboard composites

To replace Pinus taeda wood particles in particleboard manufacturing, thermally treated rice husk was studied, a little-valued raw material, renewable and abundant. This study aimed to evaluate the effect of the addition of thermally treated rice husk on the physical and mechanical properties and resistance to dry-wood termites (Cryptotermes brevis) of particleboard. For the thermal treatment, three mixing proportions of thermally treated rice husk (10%, 20% and 30%), plus the control consisting of 100% natural pine particles, were used. The thermal treatment was carried out at a temperature of 150 °C during two hours. The particleboard was manufactured by compression molding and using phenol-formaldehyde adhesive. The results show that the increase in thermally treated rice husk has no effect on the physical properties of swelling in thickness of the boards; the water absorption parameters after 2 h increased significantly by 7.9% with the addition of 30% thermally treated rice husk. The boards met the minimum requirements for static bending of the Brazilian standard, but not for front screw removal. Addition of 30% thermally treated rice husk improved the biological durability of the boards to dry-wood termites.