Ammonium pyrrolidine dithiocarbamate adsorption on copper surface in neutral chloride media

Abstract

International audienceAdsorption of ammonium pyrrolidine dithiocarbamate (PDTC) on copper surface in 0.2 and 30 g L-1 NaCl media was investigated by different electrochemical methods and surface analyses. The results from electrochemical measurements showed that PDTC adsorbs rapidly on copper surface and revealed a marked effect of mixed inhibition. Surface analyses confirm the adsorption of PDTC on copper and the formation of a Cu-PDTC complex through the S atoms of PDTC. At high concentrations PDTC prevents oxides and cuprous chloride formation. XPS results showed that PDTC bonds with cuprous species indicating the formation of Cu I-PDTC complex

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

“…The subsequent decrease in current is due to CuCl formation followed by a current increase corresponding to CuCl2 -formation [36,[38][39][40]. As for the cathodic domain, bronze is less reactive than copper as current densities are about one decade lower throughout the -0.3 to -0.9 V range, corresponding to oxygen reduction, as reported in literature [41].…”

“…As for the cathodic domain, bronze is less reactive than copper as current densities are about one decade lower throughout the -0.3 to -0.9 V range, corresponding to oxygen reduction, as reported in literature [41]. The broad cathodic peak located around -1 V is due to the reduction of tin species [41] and may also include the reduction of Cu2O [35,36,42] formed by hydrolysis of the cuprous corrosion products.…”

“…The dissolution becomes afterwards faster and oxidation of Cu into Cu + happens at higher potential (323 mV) exhibiting an anodic shift of 0.24 V. On the cathodic branch, the peak at -1V is still present but less intense: adsorption of PDTC on bronze surface during immersion may hinder oxides formation [36] and provides more protection efficiency.…”

“…It was shown that PDTC forms a selfassembled layer through sulphur/copper interactions [34]. In previous works we showed that the protective effect of PDTC might be explained by the formation of a highly stable Cu I -PDTC complex on copper surface that leads to decrease in rate of anodic dissolution and of oxygen reduction reaction [35,36]. Moreover, we carried out similar studies on AA 2024-T3 aluminium alloy that showed good corrosion protection by PDTC thanks to the formation of an adsorbed layer on Cu-rich particles [37].…”

An Investigation of Aganoerion Polymorphum Leaf Extract as a Copper Working Fluids’ Additive

“…The Joint Committee on Powder Diffraction International Centre for Diffraction Data used to analyze results. The results expressed the local around the positions as 38, 44, 65 and 73-74º correspond to corrosion products Cu 2 O (or protective layer), while the local around position of 50º correspond to substrate Cu was found [12]. Corrosion products Cu 2 O and substrate Cu in the XRD results indicated that these products combined with the product of adsorption inhibitor on copper surface.…”