Inhibitive Action of Sodium tetrafluoroborate on the Corrosion of Carbon Steel in Hydrochloric Acid Medieum

The inhibitive action of Sodiumtetrafluoroborate(NaBF4) on corrosion of carbon steel (CS) in 1.0M HCl was studied by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The measurements show that the inhibition efficiencies increase with the increasing of NaBF4 concentrations but decrease with increasing of the temperatures. This reveals that the inhibitive action of the inhibitor was mainly due to the adsorption on the carbon steel surface by blocking of the active sites. The above results showed that NaBF4 acted as a mixed-type corrosion inhibitor. The adsorption of NaBF4on the carbon steel surface obeyed the Langmuir adsorption isotherm. This was supported by the impedance measurements which showed a change in the charge transfer resistance and double layer capacitance, indicating the adsorption of NaBF4 on the carbon steel surface. Thermodynamic parameters of the studied inhibitor were calculated and discussed

Corrosion inhibition of mild steel in hydrochloric acid by 5,5',5''-(nitrilotris (methylene)) tris-(8-quinolinol) : Experimental, theoretical and molecular dynamic studies

The influence of 5,5',5''-(nitrilotris (methylene)) tris-(8-quinolinol), noted (NMQ8), on mild steel corrosion in 1 M HCl was studied by weight loss, electrochemical, scanning electron microscopy (SEM), theoretical calculation and molecular dynamic methods. The results obtained for NMQ8 showed a good inhibition effect on the mild steel in the 1 M HCl solution. The inhibition efficiency was found to increase with a corresponding increase in the NMQ8 concentration, and the best inhibition of 92.78% occurred at a NMQ8 concentration of 1 mM. The potentiodynamic studies revealed that investigated NMQ8 act as mixed type inhibitor. Activation energy (Ea), equilibrium constant (Kads), free energy of adsorption (ΔG°ads) were calculated and discussed. The studied inhibitor obeyed Langmuir's adsorption isotherm. The adsorption behavior and inhibition mechanism of studied compound on the surface of mild steel were studied by quantum chemical calculations and molecular dynamics (MD) simulations. It was found that the compound show the highest ability to donate and accepting electrons while the MD simulations show the high adsorption energy of the molecules on Fe (110) surface

Effect of chlorine group position on adsorption behavior and corrosion inhibition of Chlorobenzylideneamino-5-methyl-2, 4-dihydro-1, 2, 4-triazole-3-thione Schiff bases: Experimental study

The corrosion inhibition and adsorption of 4-(n-Chlorobenzylideneamino)-5-methyl-2,4-dihydro-1,2,4-triazole-3-thione (n-CBAT) Schiff bases has been investigated on steel electrode in 1.0 M HCl by using weight loss, potentiodynamic polarization curves, and electrochemical impedance spectroscopy (EIS) methods. The results show that all n-CBAT are good inhibitors, and inhibition efficiency follows the order:4-CBAT <3-CBAT <2-CBAT. Polarization curves reveal that all studied inhibitors are mixed type. The adsorption of each inhibitor on mild steel surface obeys Langmuir adsorption isotherm. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability. The effect of temperature on the corrosion behavior with addition of 1×10−3Mof n-CBAT added was studied in the temperature range 30–60◦C. The thermodynamic parameters activation were determined and discussed

Corrosion Inhibition Properties of Thiazolidinedione Derivatives for Copper in 3.5 wt.% NaCl Medium

Copper is the third-most-produced metal globally due to its exceptional mechanical and thermal properties, among others. However, it suffers serious dissolution issues when exposed to corrosive mediums. Herein, two thiazolidinedione derivatives, namely, (Z)-5-(4-methylbenzylidene)thiazolidine-2,4-dione (MTZD) and (Z)-3-allyl-5-(4-methylbenzylidene)thiazolidine-2,4-dione (ATZD), were synthesized and applied for corrosion protection of copper in 3.5 wt.% NaCl medium. The corrosion inhibition performance of tested compounds was evaluated at different experimental conditions using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves (PPC) and atomic force microscopy (AFM). EIS results revealed that the addition of studied inhibitors limited the dissolution of copper in NaCl solution, leading to a high polarization resistance compared with the blank solution. In addition, PPC suggested that tested compounds had a mixed-type effect, decreasing anodic and cathodic corrosion reactions. Moreover, surface characterization by AFM indicated a significant decrease in surface roughness of copper after the addition of inhibitors. Outcomes from the present study suggest that ATZD (IE% = 96%) outperforms MTZD (IE% = 90%) slightly, due to the presence of additional –C3H5 unit (–CH2–CH = CH2) in the molecular scaffold of MTZD

Corrosion Inhibition Properties of Thiazolidinedione Derivatives for Copper in 3.5 wt.% NaCl Medium

Copper is the third-most-produced metal globally due to its exceptional mechanical and thermal properties, among others. However, it suffers serious dissolution issues when exposed to corrosive mediums. Herein, two thiazolidinedione derivatives, namely, (Z)-5-(4-methylbenzylidene)thiazolidine-2,4-dione (MTZD) and (Z)-3-allyl-5-(4-methylbenzylidene)thiazolidine-2,4-dione (ATZD), were synthesized and applied for corrosion protection of copper in 3.5 wt.% NaCl medium. The corrosion inhibition performance of tested compounds was evaluated at different experimental conditions using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves (PPC) and atomic force microscopy (AFM). EIS results revealed that the addition of studied inhibitors limited the dissolution of copper in NaCl solution, leading to a high polarization resistance compared with the blank solution. In addition, PPC suggested that tested compounds had a mixed-type effect, decreasing anodic and cathodic corrosion reactions. Moreover, surface characterization by AFM indicated a significant decrease in surface roughness of copper after the addition of inhibitors. Outcomes from the present study suggest that ATZD (IE% = 96%) outperforms MTZD (IE% = 90%) slightly, due to the presence of additional –C3H5 unit (–CH2–CH = CH2) in the molecular scaffold of MTZD