Investigating the potential of casein as a sustainable material in inhibiting the corrosion of aluminum in hydrochloric acid

Abstract

In this study, the efficiency of casein in inhibiting the corrosion of aluminum in 0.1 M HCl was evaluated. Based on the weight loss data, increasing the amount of casein in the electrolyte from 50 to 500 ppm at 298 K decreased the corrosion rate of aluminum, for instance, from 2.53 to 0.58 g m−2 h−1. It was also demonstrated that with casein, the activation energy of the corrosion phenomenon increased (e.g., from 6.52 kJ/mol without casein to 27.54 kJ/mol with 500 ppm casein). The electrochemical polarization studies illustrated that in the presence of 500 ppm casein, the corrosion current density remarkably decreased from 63.09 to 6.1 µA/cm2. This was compatible with the increase in the charge transfer resistance recorded by electrochemical impedance spectroscopy. Furthermore, the X‐ray photoelectron spectroscopy and atomic force microscopy techniques confirmed the adsorption of casein on the working electrodes, which caused an enhancement in the surface quality of the specimens.

Examining the ability of palm kernel shell extract to control corrosion and assess its economic value on thermo-mechanically treated steel in artificial seawater: a sustainable and environmentally friendly approach

“…The extract is a mixed type inhibitor that is adsorbed on the metal surface and blocks the corrosion process, as suggested by the decreased corrosion current density values in the presence of inhibitor without significantly altering corrosion potential. The literature states that both physisorption and chemisorption phenomena will be considered in the corrosion inhibition when there is no discernible difference in the tafel slopes ( Ehiemere et al, 2023 ; Rabizadeh et al, 2023 ; Sofiane et al, 2023 ). From the polarization data, the PKSE had a maximum inhibitory efficiency of 96.71%, suggesting that natural chemicals can serve as a viable replacement for synthesized organic compounds.…”