Integrated Study of the Potential Application of Remediated CCA Treated Spruce Wood in MDF Production

Abstract

Public health awareness has increased in the past few years regarding the disposal of chromated copper arsenate (CCA) preservative-treated wood wastes. This study demonstrates the potential for using remediated CCA lumber and alternative fiber sources, such as sugar cane bagasse, to produce medium density fiberboard (MDF). The role of both remediated CCA loaded spruce wood and substitution of a part of it with sugar-cane bagasse fibers on the performance of MDF produced were evaluated. The remediation conditions were optimized from examining the FTIR-spectra and TGA analyses of the treated wood fibers resulted from changing the remediated pH (1.4–7.0) and temperature (20–80 °C) together with the efficiencies of removing the preservative metals. The results showed that CCA-remediated spruce fiber provided MDF with 59% and 75.5% reduction in water absorption and thickness swelling, respectively, and 93% increase in IB, compared to panels made from untreated wood. Blending both bagasse fibers with either untreated or remediated fibers had a positive impact on MDF properties. Compared to boards made with untreated control spruce fibers, boards made with up to 30% bagasse had up to 79% reduction in water absorption, 62% reduction in thickness swell, 38% increase in modulus of rupture (MOR), and 244% increase in internal bond (IB) strength. According to ANSI Standard for interior MDF, the remediated CCA-treated spruce was suitable for the manufacture of MDF, either individually or in blends with sugar cane bagasse.