Evaluation of rapid methods for detecting wood preservatives in waste wood
W J Homan, H Militz
For the disposal of wood waste under ecological sound conditions information about its hazardous potential is required. Several analytical methods are available for the detection of most elements in wood preservatives. Industrial process conditions, however, demand methods with very short turn around times. In this research several methods of analysis were judged on their speed and accuracy. A number of inorganic wood preservatives and organic preservatives containing detectable elements were studied (i.e. CCA, CCB, ZKF, CC, PCP [Cl]). Both solutions and treated wood samples were analyzed with energy dispersive X-ray fluorescence (EDXRF), laser-ablation ICP and coulometry. The coulometrical methods provided very precise analyses of solid wood in a turn around time of approximately 10 minutes. With laser-ablation ICP the results were unreliable. This is caused by the solid sample preparation procedure. EDXRF can provide reliable analyses in approximately 30 seconds. This method is not suitable, however, at low levels of concentration (< 50 ppm).