Study of the effectiveness of tannic acid on archaeological iron pieces
Keywords:
hierro arqueológico, Inhibición, ácido tánico, protección, conservación, restauraciónAbstract
The current research addresses the study of the effectiveness of tannic acid, one of the most used products in the process of inhibition of iron archaeological objects, when it comes to passivizing the corrosion products present in this type of archaeological pieces, as well as the verification of the combination of this inhibitor plus a protector, such as the acrylic resin Paraloid® B-44.
In order to carry out this research, a series of nineteenth-century iron sheets from an emergency excavation are used as specimens, to which electrochemical techniques such as the Voltammetry of Microparticles (VPM) and the Electrochemical Impedance Spectroscopy (EIS) are applied to check the effectiveness of the treatments applied to the different samples.
The implementation of these electrochemical techniques has allowed to establish significant differences between the three treatments studied: tannic acid, acrylic resin (Paraloid® B-44) and tannic acid plus Paraloid® B-44, even in the case of parts with a relatively high degree of corrosion.
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