Treatment and protection with Nanomaterial-enhanced Benzotriazole of Archaeological candlestick Housed in the French Institute of Oriental Archaeology

Abstract

This study presents an approach toward the conservation and protection of a historic brass candlestick housed in the French Institute of Oriental Archaeology in Cairo, dating from approximately 1830-1815 AD. Recognizing the widespread use of brass alloys -comprising copper and zinc-in ancient artifacts due to their aesthetic appeal and corrosion resistance, the research emphasizes the importance of advanced preservation techniques to combat environmental degradation. The artifact’s surface was subjected to detailed analytical investigations utilizing a combination of techniques including portable light microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and portable X-ray fluorescence (XRF). The analyses revealed significant surface alterations, including copper corrosion products and morphological alterations indicating surface loss and deformation due to exposure to pollutants, humidity, and chloride ions. Furthermore, the repeated thermal effects generated by the occupation of the candlestick contributed to the deterioration of the historical artifact, leading to a decline in its physical and mechanical properties and increasing its structural fragility.Conservation treatment of candlestick was performed via mechanical cleaning including the use of various brushes, scalpels, ultrasonic technique, and spatulas to effectively remove dust adhered to corrosion products covered by wax. Chemical cleaning occurred immersion the object in Rochelle salt solutions, it was immersed in distilled water to remove the chemical followed by ethyl alcohol rinses. Then, the surface was prepared by dry heating to apply the protective layer 0.5% BTA + 5mg TiO2. Benzotriazole forms protective films on brass alloy, while TiO₂ nanoparticles enhance stability, UV resistance, antimicrobial activity.