Monitoring Pollutants on Wood Residues Using FT-IR-ATR Technology

Nowadays wood residues from enterprises and recycling platforms are generally transformed in particleboards, combusted or land-filled. These residues are constituted by widely heterogeneous materials including treated/non treated wood, boards, and other wood-based products. Monitoring occurrence and concentration of pollutants (coatings, preservatives, glues, heavy metals) on wood residues is fundamental for an accurate characterization and selection of the best management for each material. The primary goal of this research is the control of pollutants on wood residues. Main benefits are: separation of polluted from non-polluted wood; sub-selection of polluted residuals in order to sort each category in an appropriate way; reduction of recycling of dangerous pollutants (otherwise continuously re-constituted in particleboards and, finally, combusted); profitable use of non-contaminated wood. This aim is reached by using FT-IR-ATR technology by creating a spectra database of pollutants and by monitoring the presence, typology, and concentration of unknown polluted wood residues. The pollutants database is constituted by known coatings, glues, and preservatives which have been analyzed wet and once dried. Wood residues with unknown contamination were sampled from wood enterprises and recycling platforms; after the same analysis, their spectra were compared to the ones in the pollutants database. Presence and typology of pollutants were successfully traced with FT-IR-ATR. Differences in spectra were clearly demonstrated using cluster analysis and "Quick compare" method. The database development and the analysis of unknown polluted samples are presented in this paper as preliminary results. This work is a part of the project BiQueen - Biomasses Quality for Efficient Energy production.