Abstract :
Ketene dithioacetal derivatives, namely 3-[bis(methylthio)methylene] pentane-2,4-dione (1), 3-(1,3-dithian-2-ylidene) pentane-2,4-dione (2)
and 3-(1,3-dithiolan-2-ylidene) pentane-2,4-dione (3) were synthesized and their respective capacity to inhibit copper corrosion in 3 MHNO3 was
investigated by means of weight loss, potentiodynamic polarization, scanning electron microscopy (SEM) and energy dispersive X-ray
fluorescence (XRF). The obtained results indicate that the addition of these compounds significantly decreases the corrosion rate. Potentiodynamic
polarization studies clearly showed that the inhibition efficiency increases with increasing concentration of the investigated compounds at a fixed
temperature, but decreases with increasing temperature. These results on the whole showed that the studied substances are good cathodic inhibitors
for copper corrosion in nitric acid medium. SEM and energy dispersive X-ray (EDAX) examination of the copper surface revealed that these
compounds prevented copper from corrosion by adsorption on its surface to form a protective film, which acts as a barrier to aggressive agents. The
presence of these organic compounds adsorbed on the electrode surface was confirmed by XRF investigations
