Effect of substitution on corrosion inhibition properties of 2-(substituted phenyl) benzimidazole derivatives on mild steel in 1 M HCl solution: A combined experimental and theoretical approach

New surfactants N‐alkyl‐N,N‐dimethyl‐N‐(3‐thienylmethylene)ammonium bromides: Preparation and anticorrosion evaluation

“…El Adnani et al found that quinoxalines with electron‐donating group (sulfur substitutes) possess higher E HOMO, Δ N and μ compared with quinoxalines with electron‐withdrawing group (oxygen substitutes), showing a higher tendency to adsorb on the mild steel surface. Dutta et al make the difference in corrosion current as a function of the difference in the fraction of charge transfer (Δ N ). It comes out that there is a good linear relationship between the corrosion current difference and Δ N .…”

Chemical Combination of 4-(4-Hydroxybut-2-ynyl) Pyridine and 3-Methylbenzenamine to Construct an Effective Inhibitor: Theoretical and Practical Investigation

“…This model assumes that the solid surface contains a fixed number of adsorption sites and each site holds one adsorbed species [40]. K adas values were used to calculate the standard free energy of the adsorption (∆G 0 ads ) of BAP molecules according to the following equation [41]: (15) Where 55.5 is the mole concentration of water, R is the gas constant (8.314 J mol -1 K -1 ) and T is the absolute temperature (K). The calculated K ads and ∆G 0 ads values of BAP are reported in Table 3.…”

“…Where υ is the corrosion rate, E a the apparent activation energy, A the pre-exponential factor, T and R have the same meaning as those in Equation (15). Figure 7 illustrates the Arrhenius plots of ln υ against 1/T in the presence and absence of BAP at different temperature.…”

“…In the presence of BAP, the value of E a is lower than that in uninhibited solution, which further confirms that the adsorption of the BAP on the surface of the X70 steel sheet is typical chemical adsorption. The activation enthalpy ∆H # and activation entropy ∆S # can be obtained from the transition state equation: (20) Where N is the Avogadro's number, h the Planck's constant, T and R have the same meaning as those in Equation (15). Plotting ln (υ/T) against 1/T yields straight lines (Figure 7).…”

“…For instance, -NH2 groups in the structures of inhibitors often act as reaction centers amino during the adsorption of inhibitors. In this way, organic inhibitors form an adsorbed protective film on metal surface, and protect metals from the attack of acid solutions [13][14][15][16]. In addition, many kinds of nitrogen-containing compounds such as pyridine and its derivatives also attract attention due to their inhibition properties for metal corrosion [17,18].…”