Theoretical and experimental evaluation of the inhibiting power of 4-amino,5-phenyl-1,2,4-triazole,3-thione against corrosion copper in a neutral chloride environment

In this study, we first developed the synthesis of 4-amino-5-phenyl-1,2,4-triazole-3-thione (APTS) and then its identification based on 1H and 13C NMR spectral data.  The product's ability to prevent copper corrosion in a 3% NaCl solution was then evaluated. This work was carried out by stationary and transient electrochemical techniques, supplemented by a theoretical study. The results obtained showed that the APTS provides good protection of copper in the corrosive environment by the formation of a protective layer adsorbed on the metal surface. The inhibitory efficiency achieved is around 98% for a concentration of 10-3M in inhibitor justifying its protective effect. The theoretical study of the interaction of APTS with metallic copper shows that this inhibitor adsorbs on the metallic surface by forming chemical bonds between the metal and the inhibitor. This confirms the experimental result

Coupling of electrochemical, electrogravimetric and surface analysis techniques to study dithiocarbamate/bronze interactions in chloride media

International audienceInteraction between ammonium pyrrolidinedithiocarbamate (PDTC) and bronze in 30 g L-1 NaCl was investigated at several concentrations between 0.1 and 10 mM by means of various electrochemical and spectroscopic techniques. Electrochemical measurements revealed a fast adsorption process of PDTC on Cu and Pb and the formation of a thick insulating and protective film with a high surface coverage. At high concentrations, PDTC prevents oxides formation. Surface analyses confirm PDTC adsorption on bronze mainly via interaction between sulphur atoms and Cu sites to form Cu I-PDTC complex