Effects of recovered wood on the formaldehyde release of particleboards

Abstract

Three-layer polymeric diphenyl-methane-diisocyanate (pMDI)-bonded particleboards (PBs) were produced with different proportions of simulated recovered wood (rW) in the core layers (cLs) to assess the effect of rW on the formaldehyde (FA) release of PB. A pre-test was conducted on furniture and particle mixtures of rW to determine the range of expectable FA emission of rW. The FA content of the raw particle mixtures could be predicted from the contents of the individual raw material and did not change compared to the PB. FA content correlated strongly with PB-FA emission. It was possible to predict the maximum PB-FA contents, which should not be exceeded according to F**** and CARB 2 by linear regression models. At moderate and high total FA emission levels, the FA emission of the particle mixtures was approximately 60% higher than the emission of PB blocks. At low total FA level, the flask method and the gas analysis method exhibited different results with regard to the emissions from particles and their respective PBs.

Evaluation of Dynamic Microchamber as a Quick Factory Formaldehyde Emission Control Method for Industrial Particleboards

“…e current trend in the industry is to use more recycled wood in particleboard production. Recycled wood has higher emission levels, especially if the share of particleboards in the recycled mix is high [19]. It should be noted that some of the particleboards found in the recycled mix might have been produced before the emission limit in Europe was lowered to 0.1 ppm.…”

“…us, when recycled wood is used in production, control of the incoming wood mix is extremely important for keeping the emissions low. Himmel et al [19] managed to predict the formaldehyde emissions of pressed particleboards from the formaldehyde content of the raw materials or from the adhesive-free particle mat for different recycled material sources.…”