The pharmacist Johann Heinrich Linck senior (1674-1734) created the xylotheque (collection of wood species) in Leipzig, Saxony (Germany). His son, Johann Heinrich Linck junior (1734-1807), continued the valuable and unique collection, which now belongs to the Museum Waldenburg near Dresden, Germany. In the past the cupboard, including the wood specimens, was impregnated with a wood preservative containing dangerous pesticides. Consequently, the removal of these pesticides was necessary prior to the restoration.The furniture surface was cleaned with a special detoxification agent mainly made of orange terpenes, which could not be applied to the more sensitive xylotheque specimens. Liquid carbon dioxide was favored for their decontamination. A prototype of a plant at Amsonic, Switzerland, was available for decontamination. This prototype is the topic of a research project to develop a procedure to clean sensitive industrial goods with liquid carbon dioxide.Preliminary testing of the procedure was carried out on several test specimens from new and old timber with and without impregnation using “Hylotox 59”, imitating the historical specimens. The efficiency of pesticide reduction was determined by x-ray fluorescence spectrometry (XRF) and gas chromatography (GC).It was noted that most test specimens showed no marked changes in their properties and shape. Exceptions were test specimens with high resin content. The amount of pesticides could be reduced considerably on the surface of the specimens. However, leaching of pesticides over the whole cross-section of the test specimens was incomplete. Therefore, prior to the detoxification of the timber boards additional experiments need to be carried out to optimize the parameters of the process with regard to the decontamination rate.

Download document (413 kb)
free for the members of IRG. Available if purchased.

Purchase this document