Lösemittelhaltige Gelkompressen

Eine neue Methode zur Schadstoffreduzierung biozidbelasteter Objekte aus Holz

Abstract

Solvent-containing gel compresses. A new method for reducing pollutants in biocide-contaminated wooden objects
Until the 1990s, chemical wood preservatives such as pentachlorophenol (PCP) and gamma-hexachlorocyclohexane (lindane) were used to protect buildings and works of art from pests. Today, they are considered to be harmful to health, which is why practical methods for reducing harmful substances are needed for permanently installed objects such as church pews, organs, wall panelling or supporting structures. As part of the ZIM project 'RWTec-DeTox', an innovative process for surface decontamination was developed that works with solvent-based gel compresses. The gel, which is thickened with cellulose, can be easily applied to differently shaped surfaces and adheres largely independently. Decontamination is achieved by molecular diffusion in two stages, solvent exposure and solvent evaporation. This new method for reducing harmful substances on wooden surfaces was tested in three model trials accompanied by the Bayerisches Landesamt für Denkmalpflege (Bavarian State Office for the Preservation of Historical Monuments). The results showed high decontamination rates of the biocides PCP and lindane of over 80 % in the first 2 mm of the object surface. Solvent-based gel compresses are an innovative method for reducing harmful wood preservatives and could be widely used in the future for the protection of historical monuments, especially for stationary objects.