Corrosion Inhibition of Mild Steel in Strong Acid Environment by 4-((5,5-dimethyl-3-oxocyclohex-1-en-1-yl)amino)benzenesulfonamide

Abstract

Newsulfanilamide derivative namely 4- ((5,5-dimethyl-3oxocyclohexenyl)amino)benzenesulfonamide (DOBF) was synthesized and the chemical structure was elucidate using Nuclear Magnetic Resonance (NMR) and elemental analysis (CHN). The inhibition effects of a studied DOBF on the corrosion of mild steel in 1 M hydrochloric acid environment were investigated using electrochemical impedance spectroscopy (EIS), weight loss method and scanning electron microscopy (SEM). The synthesized inhibitor concentrations were 0.1 mM to 0.5 mM and the temperatures ranging from 303-333 K. Results showed that the inhibition occurs through adsorption of the inhibitor molecules on the metal surface. Electrochemical and weight loss techniques revealed that the tested DOBF act as superior inhibitor for acidic corrosion of mild steel and the efficiency increase with increasing concentrations. EIS results revealed that DOBF demonstrate the highest inhibition efficiency of 93.70 %, at a concentration of 0.5 mM. The adsorption of the investigated inhibitor obeys Langmuir's adsorption isotherm. Different thermodynamic parameters have been calculated and discussed. SEM confirmed the formation of a protective film on the surface. The investigated techniques are in good agreement to establish the using DOBF as corrosion inhibitor for mild steel in strong acid environment. It was found that the corrosion inhibition performance depends on the concentration of the DOBF and the solution temperature. Quantum chemical calculations have been done to correlate the electronic characteristics of the compounds with the corrosive inhibitive impact. The quantum calculations such as the HOMO, LUMO, energy gap (ΔE), atomic charges, dipole moment (μ), electron affinity (A), chemical hardness (η), softness (σ) electronegativity ( ), ionization potential (I), and fraction of electrons transferred (∆ ), were used to explain the mechanism of inhibition of DOBF molecules on the mild steel surface. Experimental and theoretical results are in good agreement.

Inhibition of Mild Steel Corrosion by 4-benzyl-1-(4-oxo-4-phenylbutanoyl)thiosemicarbazide: Gravimetrical, Adsorption and Theoretical Studies

“…) and protection efficiency ( %) were determined from gravimetrical measurements based on Equations (1) and ( 2) respectively [14,15].…”

“…After 1, 5, 10, 24 and 48 h of exposure period in 1 M HCl solution in absence and presence of tested inhibitor at various concentrations (100, 200, 300, 400, 500 and 1000 ppm), the coupon was removed, soaked with double-distilled water, washed with acetone, dried in oven and weighed by electronic balance. The rate of corrosion rate C R ; mmy −1 and protection efficiency (IE%) were determined from gravimetrical measurements based on Equations (1) and ( 2) respectively [14,15].…”

Performance of D-galactose for Protecting The Corrosion Rate of Aluminium Alloy 5052 (AA5052) in Acidic Environment

“…The chemical reactions may occur between a strong acid and metal resulting from the oxide layer; hence, their surfaces become defects. In certain concentrations, the strong acids can easily oxidize the metal surface [14], dan hence decreasing the duty life of bipolar plate in the PEMFC system. The defective pattern on the G-AA5052 surface was thinner and more uniform than the AA5052.…”

Inhibition Evaluation of 5-(4-(1H-pyrrol-1-yl)phenyl)-2-mercapto-1,3,4-oxadiazole for the Corrosion of Mild Steel in an Acidic Environment: Thermodynamic and DFT Aspects

“…The quantum electronic parameters of the most stable conformers were calculated of the DFT. HOMO, LUMO, ΔE, η, σ, χ, and ΔN were calculated using equations (4-8) [29,30].…”