Evaluation of Vicine as a Corrosion Inhibitor for Carbon Steel Alloy

Abstract

In the present study, vicine was extracted from sunflower seeds, and has been evaluated as a corrosion inhibitor for carbon steel alloy, at different concentrations and temperatures. Vicine showed maximum inhibiting efficiency of 97%, at 25 ºC. The inhibitor's efficiency was reduced when the temperature increased. Kinetic parameters (Ea, ΔH*, ΔG* and ΔS*) were calculated. The corrosion reaction was suppressed by vicine, because the energy barrier of the corrosion reaction was increased, and it became non-spontaneous, by an endothermic process. Furthermore, ΔHads, ΔGads and ΔSads were also calculated, and showed that the inhibitor was physically adsorbed by a spontaneous and exothermic process. The corrosion was inhibited by simple blocking the reaction sites. The adsorption process obeyed the Langmuir adsorption isotherm. The theoretical and experimental studies depicted that the inhibitor worked by a mixture of physicalchemical adsorption modes.

Ziziphus Spina Christi Leaves Methanol Extract Evaluation as Antifungal, Antibacterial, Antioxidant and Green Inhibitor for Carbon Steel Alloy Corrosion in Hydrochloric Acid

“…13 show that, as temperature increased, Icorr and CR values were higher, while Rp and IE% values were lower. These values can be attributed to the kinetic energy reduction for the corrosive molecules, whether without or with inhibitor [37][38]. In this study, to better understand C1010 corrosion reaction behavior, without and with inhibitor, kinetic parameters were calculated according to Arrhenius equation [39]:…”

Experimental study and mathematical modelling of the corrosi-on inhibition of mild steel with an organic compound in 1 M HCl

“…Experiments were conducted under total immersion of mild steel specimens in the stagnant and aerated conditions, using 250 mL capacity beakers. After being weighed accurately with high sensitivity balance, the specimens were immersed in 100 mL of 1 M HCl with and without various concentrations (5×10 -6 -10 -3 M) of PDDY at various temperatures (20,30,40, 50 and 60 °C) in aerated conditions. After 3 hours of immersion, the specimens were taken out, rinsed thoroughly with distilled water, dried and weighed accurately again.…”

“…Corrosion of mild steel in 1 M HCl in the absence and presence of various concentrations (5×10 -6 , 10 -5 , 5×10 -5 , 10 -4 , 5×10 -4 and 10 -3 M) of PDDY was studied by weight loss experiments at various temperatures (20,30,40,50 and 60 °C). The corrosion rate (CR) in mg cm -2 h -1 and values of inhibition efficiency, obtained by 30 test runs of weight loss measurement after 3 hours of immersion in 1 M HCl solution, are summarized in Table 1.…”

“…metal surface is less protective at higher temperatures, since the desorption rate of the inhibitor is greater at higher temperatures [30]. Thermodynamic parameters of the corrosion reaction, namely activation energy Ea, entropy (∆Sa) and enthalpy (∆Ha) were calculated using Arrhenius equation ( 9) and transition state theory equation [19]:…”

Potentiometric Study of Rhenium(v) Complex Formation With Azathioprine and Ceftriaxone

“…CE is evaluated as a corrosion inhibitor for carbon steel alloys in the presence of 0.5 M hydrochloric acid (HCl) at different concentrations, i.e., 10-50 ppm and different temperatures [13]. Studies of the mechanism, kinetics and thermodynamic constants of VO(II) and Cu(II) complexes with CE in the pH range of 2 -5 at temperatures of 303, 313, 323 and 333 K, using reversed phase HPLC and ion exchange HPLC were reported [14].…”