Performance and Efficiency of Cirsium arvense Leaves Extract (CALE) as an Eco-Friendly Inhibitor for Carbon Steel in 1.0 M HCl

Current research aims to develop non-toxic, biodegradable, and environmentally friendly inhibitors. This study assessed the ability of Cirsium arvense leaf extract (CALE) to inhibit carbon steel corrosion in molar hydrochloric acidic conditions. Using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) methods, the inhibitory effectiveness η% of (CALE) was evaluated. The effects of inhibitor temperatures (293-323K) and concentrations (200–800 ppm) were studied. With 600 ppm of (CALE) at 293K, the optimal η% of 94% was obtained. The Nyquist graphs demonstrate how rising (CALE) concentration reduces double-layer capacitance and raises charge-transfer resistance due to the (CALE) molecules' adsorption on the CS surface. A mixed-type inhibitory behavior was demonstrated via potentiodynamic polarization.