Ionic nanoparticles in heritage conservation; treatments for the Mary Rose timbers

A potential method for the de-acidification of water-logged archaeological wood is through a treatment with alkaline nanoparticles. To provide information on the process we have measured the penetration of strontium carbonate nanoparticles in fresh oak blocks from dispersions of water and 2-propanol. The diffusion coefficient into the wood from aqueous dispersions is similar to 3 x 10(-12) m(2) s(-1). The diffusion is slower from the alcohol dispersion. Diffusion is also slower for samples treated with PEG200. X-ray absorption studies show that iron sulfates in wood are converted to siderite and goethite, removing the potential for the formation of sulfuric acid. (C) 2012 Elsevier B.V. All rights reserved.