RT Book, Section
T1 Calcium and magnesium alkoxides for conservation treatment of stone and wood in built heritage
A1 Favaro, Monica
A1 Chiurato, Matteo
A1 Tomasin, Patrizia
A1 Ossola, Franco
A1 El Habra, Naida
A1 Brianese, Nicola
A1 Svensson, Ingemar
A1 Beckers, Erwin
A1 Pérez, Vicente Javier Forrat
A1 Sánchez, Maria Dolores Romero
A1 Bernardi, Adriana
AB In the frame of the EU-project NANOMATCH new consolidants based on metal alkoxides were developed and tested. New compounds were prepared with different synthetic pathways to overcome the oligomerization issue, which can strongly influence solubility and therefore application of alkoxides as conservation materials for built heritage. Calcium alkoxides react in presence of humidity and carbon dioxide to give CaCO3 and alcohols. This peculiar behavior -in atmospheric conditions- makes this class of chemicals suitable for consolidation of carbonate stones, plasters and wall paintings and also for pH buffer to avoid acidification of cellulose based materials such as wood and paper. Within the frame of the project, it has been demonstrated that the developed calcium compounds are more soluble than the corresponding commercial Ca-bearing consolidants and, after reaction with air, they evolve into different calcium carbonate structures, i.e. amorphous carbonate or crystalline calcite and vaterite. The ratio among these forms can be oriented by environmental conditions and treatment with water, in order to force a carbonate phase in place of other ones. Commercially available magnesium alkoxides solutions were also tested as consolidants precursors. Carbonation of magnesium compounds brought to precipitation of low crystalline Mg hydroxide and carbonate coatings. Moreover, hydrated Mg carbonate phases were identified. Many of them are salts sensitive to water and prone to ion-exchange, possibly evolving to soluble magnesium salts deleterious for stone. These experimental evidences led to the decision to discard magnesium alkoxides for conservation purposes.
PB Springer
SN 2198-7300
YR 2015
FD 2015
LK https://hdl.handle.net/11556/2162
UL https://hdl.handle.net/11556/2162
LA eng
NO Favaro , M , Chiurato , M , Tomasin , P , Ossola , F , El Habra , N , Brianese , N , Svensson , I , Beckers , E , Pérez , V J F , Sánchez , M D R & Bernardi , A 2015 , Calcium and magnesium alkoxides for conservation treatment of stone and wood in built heritage . in Research for Development . Research for Development , Springer , pp. 413-422 . https://doi.org/10.1007/978-3-319-08533-3_35
NO Publisher Copyright: © 2015, Springer International Publishing Switzerland.
NO Acknowledgment The European Commission is kindly acknowledged for the financial support to NANOMATCH project (FP7/2007-2013: grant agreement no. 283182).
DS TECNALIA Publications
RD 27 jul 2024