Application of Ca(Zn(OH)₃)₂·2H₂O (CZ) and MgO Nanoparticles for Consolidation Stones

Keywords

limestone, environmental, nanoparticles, sol-gel method, absorption

Abstract

The limestones were important materials for pre-Hispanic civilizations; they were used to construct significant buildings and structures that played a crucial role in their culture. However, environmental factors have contributed to their deterioration, leading to their loss. Therefore, it is essential to conduct multidisciplinary research to develop new conservation treatments compatible with these materials.
This research evaluated the behavior of Ca(Zn(OH)₃)₂·2H₂O (CZ) y MgO nanoparticles applied on stones samples. Firstly, the nanoparticles were synthesized using the sol-gel method and subsequently characterized by X ray diffraction (XRD) and scanning electron microscope (SEM). Therefore, it was applicated by dropwise on stones samples. Their effects were evaluated using non-destructive techniques, specifically velocity of ultrasound propagation (Vp) and contact angle measurements. The results showed that both treatments had a consolidated effect on the stones, with a significant increase on Vp recorded after the application. Additionally, variations in the contact angle were observed in the stones treated with CZ and MgO. Specifically, Stones treated with MgO reported lower contact angles values. This increased hygroscopicity behavior to suggest an enhances their water absorption capacity.

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