Investigate the Corrosion Inhibition of Mild Steel in Sulfuric Acid Solution by Thiosemicarbazide

Abstract

Corrosion inhibition of mild steel in 0.5 mol/L H2SO4 was investigated in the absence and presence of different concentrations of thiosemicarbazide. The inhibition efficiency of thiosemicarbazide was studied by electrochemical impedance methods, potentiodynamic polarization and scanning electron microscopy at different inhibitor concentrations. Inhibition efficiency, corrosion rate and surface coverage were evaluated at different concentrations of thiosemicarbazide. Electrochemical impedance plots indicated that the presence of the inhibitors increased the charge transfer resistance of the corrosion process, increasing the inhibition efficiency. Polarization curves showed that this compound acted as mixed type inhibitor. The results of the investigation showed that this compound had good inhibiting properties for mild steel corrosion in 0.5 M sulfuric acid. The adsorption isotherm studies showed that Thiosemicarbazide adsorbed chemisorbed and formed a stable surface complex on the mild steel surface. And Langmuir obeyed the adsorption isotherm. Scanning electron microscopy analysis shows that, the surface morphology of the polished mild steel in the presence of thiosemicarbazide as inhibitor is smoother surface as compared with polished mild steel specimen in the absence of inhibitor.

Functionalization Strategies for Electropolishing Process of Carbon Steel Using Novel Quinazoline-4-one Derivatives: Synthesis, Spectroscopic Characterization, and DFT Studies

“…The EP’s representational I – V curves demonstrated three distinct zones respective to pitting, polishing, and gas development on the anode surface, which varied depending on the voltage applied. Table shows the polarization curves acquired by gradually increasing the cell current and measuring the steady-state anode, as well as the I L calculated by extrapolating linear sections of the solubility potential to the crossing of the congruous solubility current. , …”

“…Table 2 shows the polarization curves acquired by gradually increasing the cell current and measuring the steady-state anode, as well as the I L calculated by extrapolating linear sections of the solubility potential to the crossing of the congruous solubility current. 10 , 39 …”

“…The protons of the aromatic rings derived from both Quinazolineyl and phenyl moieties appeared in the 8.17 2 shows the polarization curves acquired by gradually increasing the cell current and measuring the steady-state anode, as well as the I L calculated by extrapolating linear sections of the solubility potential to the crossing of the congruous solubility current. 10,39 In addition to what has been mentioned, the data from polarization curves were collected for 8 M H 3 PO 4 solution in the nonexistence or existence of BOA at 298 K and various concentrations in Table 2. It is evident that decrease in the I L is affected with the supplement of BOA, and the anodic polarization manner of Fe is reactive to the minor concentricity of BOA.…”

“…They proclaimed that these organic additives act as inhibitors as they can diminish the EP rate of C-steel by adding inappreciable concentration. − Organic additives are adsorbed in the exposed region by forming a covalent bond (chemical adsorption) or electrostatic attraction between the admixture and the metallic part (physical adsorption). These compounds are adsorbed and shape a shielding layer at the exposure area of the anode. − …”

Synthesis, Characterisation and Corrosion Inhibition of Mild Steel by Butyltin(IV) 2-Acetylpyridine 4-Methyl-3-Thiosemicarbazone in HCl

“…It can be interpreted from the Nyquist plots that the pattern of impedance curves was not affected by the inhibitors [54]. It should be noted that the Nyquist plots displayed a divergence from the ideal semicircles that could be due to frequency dispersion affected by non-homogeneity or roughness of metal surface during metal dissolution [55,56]. The impedance spectra also showed that the semicircle and the diameters incremented with an increase in the concentration of inhibitors.…”