Lornoxicam & Tenoxicam Drugs as Green Corrosion Inhibitors for Carbon Steel in 1 M H₂SO₄Solution

Abstract

:Inhibition performance of Lornoxicam & Tenoxicam against corrosion of carbon steel in 1 M H 2 SO 4 solutions was investigated by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The inhibition efficiency increased with increasing inhibitor's concentration, but decreased with increase in temperature. Potentiodynamic polarization curves showed that, the inhibitors were of mixed type. The apparent activation energy ( ) and other thermodynamic parameters for the corrosion process have also been calculated and discussed. The inhibition of carbon steel corrosion is due to the adsorption of the inhibitor molecules on the surface, which follows Temkin adsorption isotherm. The mechanism of inhibition was discussed in the light of the chemical structure of the undertaken inhibitors.

Experimental and theoretical study on the corrosion inhibitor potential of quinazoline derivative for mild steel in hydrochloric acid solution

“…The mechanism of adsorption on the metal surface involves donation and acceptance of electrons between the molecule and metal surface. HOMO orbital is associated with donation of electrons, while LUMO orbital is associated with acceptance of electrons [15,26,42]. The results of important quantum chemical parameters of the studied molecule are presented in Table 5.…”

“…The theoretical value of M for bulk metal is given as 7 eV, while ηM = 0 eV. Note also, that the electrophilicity index ( ) has recently been defined as [15,43,45]:…”

“…Ozturk, [14] synthesized and studied corrosion inhibition behavior of two quinazoline derivatives di-cationic surfactants in acidic solutions. Pradeep et al [15] synthesized three new quinazoline derivatives and studied them as corrosion inhibitors for mild steel surface protection in HCl solution, using experimental and DFT methods. Fouda et al [16] also documented quinazoline derivatives as green corrosion inhibitors for carbon steel in hydrochloric acid, employing weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy and scanning electron microscopy.…”

Green inhibitor of carbon steel corrosion in 1 M hydrochloric acid:Eruca sativaseed extract (experimental and theoretical studies)

“…This one was confirmed in this investigation, which revealed that the equilibrium constant was significantly higher than in earlier studies. 100,101 Langmuir isotherms were found to provide a better explanation for the adsorption method of Eruca sativa seed extract on the carbon steel surface than Henry due to the precision of R 2 . The Gibbs free energy adsorption values are intended using eqn (17) .…”

Impedance Spectroscopy Studies on Corrosion Inhibition Behavior of Synthesized N,N’-bis(2,4-dihydroxyhydroxybenzaldehyde)-1,3-Propandiimine for API-5L-X65 Steel in HCl Solution

“…The inhibitor adsorption depends on parameters such as the surface charge and nature of the metal, the inhibitor structure, aggressive media type and the extent of aggressiveness and also on the nature of its interaction with the metal surface [6]. Generally the organic compounds containing hetero atoms like O, N, S and P are found to work as very effective corrosion inhibitors [7]. The choice of the inhibitor is based on two considerations, firstly economic consideration and secondly, high inhibition efficiency.…”