Thick-target PIXE analysis of trace elements in wood incoming to a pulp mill

Trunk-wood samples of wood raw material incoming to a pulp mill were analysed by thick-target particle induced X-ray emission (PIXE). The tree species studied were pine and spruce from Finland. birch from Finland and Poland and eucalyptus from Uruguay. The wood samples were dry ashed to 550degreesC prior to the analysis in order to increase the,sensitivity of the method. The method was calibrated and validated using, some wood based certified reference materials. The elements determined with the method were P. S. K. Ca. Ti. Mn. Fe. Ni, Zn, Pb, Sr, Rh, Ba and F. The concentrations of the main elements P. S. K. Ca and Mn exceeded 50 ppm in most wood samples, The concentrations of heavy metal ions like Cu, Ni and Pb in the studied were below or close to 1 ppm, The ash content of birch. pine and spruce wood were in the range 0.2-0.4% and that of eucalyptus ca 0.59%.