Study on Corrosion Inhibition and Adsorption Behavior of Calcium Lignosulfonate on Pure Copper Grounding Material in Korla Soil Simulated Solution

Abstract

In order to investigate the corrosion inhibition efficiency of calcium lignosulfonate (CLS) added to the Korla soil simulation solution on pure copper grounding material and its adsorption behavior on the surface of pure copper grounding material， the effect of CLS in the Korla soil simulation solution on the corrosion behavior of pure copper grounding material was studied using potentiodynamic polarization curves and electrochemical impedance spectroscopy.Results showed that as the concentration of CLS increased within the range of 2.27×10-4 to 9.08×10-4 mol/L， the corrosion inhibition efficiency of Cu was found to gradually increase.This increase suggested that the addition of CLS effectively inhibited the corrosion reaction process of Cu， categorizing CLS in the soil simulation solution system as an anode corrosion inhibitor.Analysis of the Mott-Schottky curves revealed that the film formed on the Cu surface in the soil simulating solution possessed the characteristics of a P-type semiconductor film.It was also observed that as the concentration of CLS increased within the range of 2.27×10-4 to 9.08×10-4 mol/L，the concentration of NA decreased， enhancing the protectiveness of the semiconductor protective film on the Cu surface.Additionally， the fitting of the three adsorption isotherms demonstrated that the adsorption of CLS inhibitor molecules on the Cu surface tended more towards the Langmuir model.In the concentration range of 2.27×10-4 to 9.08×10-4 mol/L， the ΔGm values of CLS on Cu surface varied from -37.00 to -20.00 kJ/mol， indicating that the adsorption of CLS on the Cu surface was a mixed process， controlled by both physical and chemical adsorption.

Keywords

• korla soil simulation solution|pure cu grounding material|calcium lignosulfonate|corrosion inhibition|adsorption