Synthesis and characterization of magnetic sponge nanocomposite for cleaning archeological lime stones

Abstract

Sponge-like magnetic nanocomposite consisting of magnetic nanoparticles Fe3O4 associated with a polyacrylamide gel matrix has been synthesized and can be used as an active nanomagnetic container for water-based detergent formulations as oil-in-water microemulsions. This prepared system was applied for gentle, controlled and selective cleaning of the archeological lime stone from iron rust and undesired residues. The embedding of magnetic nanoparticles Fe3O4 into the gel matrix was proved by IR spectroscopy and scanning electron microscopy SEM, showing that the magnetic nanoparticles were successfully embedded in the gel structure. The lime stone samples with corrosion stains were cleaned using the prepared magnetic sponge nanocomposite carrying the water based detergent, followed by characterization of the surface of the samples before and after treatment through SEM, X- ray Florescence XRF and colour measurements. SEM images confirmed the full removal of stains. XRF analysis detected decreasing of the iron oxide ratio from 10.62% to 0.26% after cleaning. The colour measurement recorded the colour changes of the samples' surface before applying of the iron rust and after treatment with the prepared cleaning system and it was that the colour changes were with acceptable ratio and cannot be visible by naked eye.