Haloxylon salicornicum extract as an eco-friendly corrosion inhibitor for carbon steel in HCl solution

The Haloxylon salicornicum (HS) extract ability to prevent carbon steel alloy (CS) from corroding in 1 M HCl was investigated. Research methodologies included electrochemical techniques like potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques as well as chemical method like weight loss (WL). The extract provides 94.1% inhibitory efficiency (IE) to carbon steel (CS) submerged in a one molar HCl solution at 300 ppm, according to the gravimetric method. The inhibition efficiency of the HS extract increases with increasing the concentration and decreases with temperature, from 25 to 45 degrees C. Polarization (PDP) study revealed that the extract was a mixed type of inhibitor. The obtained results from EIS revealed that the gradual increase in the HS concentration and time of immersion leads to progressive increase in IE. Impedance responses showed that the corrosion process occurred under diffusion control. The HS's adsorption adhered to the Langmuir adsorption isotherm, and the extract species' mixed kind (both physical and chemical) of adsorption on the metal surface was suggested by the adsorption's free energy. The adsorbed film on CS surface was confirmed using atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS) techniques and was supported by electrochemical studies. Activation parameters were determined in the presence and absence of HS. Hence, HS extract has good corrosive inhibitive effect on carbon steel in HCl solution. It turned out that all methods used were consistent with one another.