Stable dispersions of Ca(0H)2 in aliphatic alcohols: properties and application in cultural heritage conservation

The kinetic stability of dispersions of Ca(OH)₂ particles (1-2 µm) in short-chain aliphatic alcohols was investigated. The alcohols were shown to strongly enhance the kinetic stability with respect to water. Ca(OH)2 crystalline nanoparticles were also synthesised at 60 °C from aqueous supersaturated solutions. The nanoparticles were characterised by scanning electron microscopy and atomic force microscopy techniques. The kinetic stability of the Ca(OH)₂ nanoparticle dispersions was higher than that of the micron-sized particles. Dispersions of the nanoparticles in 1-propanol were successfully tested as consolidating on aerial mortar and carbonatic stone specimens. Applications of these dispersions on carbonatic stones presenting flaking and powdering from architectonic sites in Rome and near Padua gave positive results.