Study and synthesis of organic precursors for salt treatments developed to protect and strengthen building materials and frescos

An attempt to find out possible ways to synthesise sulphates and oxalates, to be utilised for strengthening and consolidating limestone and frescos surfaces was made. Particularly organic sulphates were prepared and tested for their reactivity with barium salts, trying to obtain slow sulphates hydrolysis and, so, BaSO4 precipitation. Different solutions were applied on Opificio delle Pietre Dure´s standards using different methodologies and applications times. The characterisation of chemical interactions between carbonaceous bodies and solutions was done by X-ray diffraction (XRPD), Fourier transformed infrared spectroscopy (FTAR), scanning electron microscopy (SEM-EDS). The synthesis of organic sulphates resulted not difficult and the solutions are very easy to use. More difficult was oxalate synthesis. The application results are promising.