Th e inhibit ion effect of a new Schiff ba se on mild steel in ۲ M HCl . A complete study : Adsorp tion, temperature, duratio n and qua ntum ch emical aspects

Iron an d its alloys are widely used in industry. Mild steel is one of the important iron containing alloy u sed in different applications and is susce ptible to c orrosion du e to its thermodynamic instability esp ecially in a ggressive media [۱]. In order to reduce the degree of metal a ttack and rate of co nsumption of the aci d, corrosio n inhibitor s are adde d to the picklin g solutions. Most of the well kno wn acid inhibitors are organic com pounds containing nitrogen, sulphur and/or oxygen atoms, w hich allow an adsorption on the metal surfac e [۲, ۳]. In this study, The inhibition of corrosio n of mild steel in ۲ M HCl by a Schiff base (Fig. ۱) have been inv estigated using weight loss method, electroche mical tec hniques (potentiodynamic polarization and electrochemical impedance spectrosco py (EIS)). Effect of temper ature on the mechanis m and also on the effi ciency of th e corrosio n inhibition process was studied using the Arrhenius approxi mation of th e rate law. Polarization experiments were perform ed at different soluti on temperatures. Thermodynamic parameters for the corrosion process were obtained and interpreted. The adsorption of the in hibitor, on the steel su rface in the acid medium ( ۲ M HCl) obeyed the L angmuir a dsorption isotherm.

کلیدواژه ها:

Mild steel ، EIS ، Polarisation ، Acid corrosion