An evaluation of the influence of heat treatment on the preservative retention in ash wood (Fraxinus excelsior L.)

As high temperature followed by preservation may cause many different, sometimes contrary changes in wood properties, the aim of this paper was to determine the retention and possible distribution of copper containing preservative in ash wood with an X-ray spectrometer. Two solutions corresponding to the final retention 2 and 4 kg/m3 were applied as preservative for model laboratory scale low-pressure preservation of ash wood. Before preservation was made, samples were heat treated for 2 or 6 hours at 180°C, apart from the control samples. The mapping option of the X-ray spectrometer was applied and the surface on the half-cut cross-section was analysed. Copper was acknowledged as the retention indicator. On the basis of the results obtained, it can be assumed that the heat treatment improves the treatability of samples with the parameters used. Longer treatment durations increase the uptake of the preparation solutions.