Despite of insufficient fixation, copper based preservatives belong to the group of the most frequently used and effective wood preservatives. As copper compounds do not react with wood in the absence of biocides, ethanolamine is introduced into the preservative solution. Influence of spruce wood ring width on fixation of copper based preservatives was studied. Spruce wood specimens were vacuum impregnated with 2 different copper based preservatives namely: commercial preservative Silvanolin and aqueous solution of copper sulphate of 3 different concentrations. Impregnated wood specimens were dried 4 weeks and afterwards leached according to the SIST EN 1250/2 procedure. Atomic absorption spectroscopy was used to determine copper content in collected leachates. The results show, that copper fixation is much better at the specimens with narrow ring width compared to the ones with wide ones. Furthermore, it was proved, that copper leaching was more prominent at specimens impregnated with aqueous solution of copper(II) sulphate compared to Silvanolin impregnated specimens. This is another prove, that ethanolamine can significantly improve copper fixation in wood in this way influencing smaller leaching of copper.
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