Application of lentil seed extract as an inhibitor to assess the corrosion properties of copper–nickel alloys in a NaCl environment

Abstract

Weight loss (WL), electrochemical, and surface analysis were used to explore the efficiency of lentil seed extract (LSE) in mitigating the electrochemical corrosion of Cu–10Ni and Cu–30Ni alloys in obviously aerated water. The adsorption of lentil seed extract (LSE) species to create a barrier layer improved the corrosion resistance of Cu–Ni alloys in a NaCl medium. It was shown that the temperature of the medium and the amount of extract used affected the enhanced inhibitory efficacy. Using the PDP approach, the Cu–10Ni alloy showed the maximum inhibition performance (IE) of about 98.58% and 8.53% with 300 ppm LSE, respectively. According to the findings, the studied extract had a good ability to slow down the step at which alloys corroded in a 3.5% NaCl solution. It was discovered that as the temperature rose, the rate of corrosion increased. The thermodynamic activation functions of the dissolution process were also calculated as a function of extract dose. PDP curve analysis reveals that LSE is a mixed-type inhibitor, and EIS findings demonstrates that increasing dose not only alters the charge transfer (R_ct) of Cu–10Ni alloy from 1031 to 2984 Ω cm² and for Cu–N30Ni alloy from 3093–6208 Ω cm² but also changes the capacitance of the adsorbed double layer (C_dl) for Cu–10Ni alloy from 728–678 μF cm² and for Cu–30 Ni alloy from 726 to 701 μF cm². The inhibitor's adsorption provides a good fit for the “Freundlich, Temkin, and Langmuir isotherm” models. Several methods are used to confirm that the alloy surface has a protective coating.