Obtaining ionic liquids based on 2-allyl-4-isododecylphenol and studying their hydrogen sulfide corrosion inhibition property on steel St.3

The article presents the results of anticorrosive gravimetric studies of ionic liquids (comp.I and II) obtained by quaternization of aminomethylated derivatives of 2-allyl-4-isododecylphenol with hydrogen chloride (I was obtained based on 2-allyl-4-isododecyl-6-diethylaminomethylphenol, and II was obtained based on 2-allyl-4-isododecyl-6-morpholinomethylphenol.Their structures were determined by NMR spectroscopy.The tests were carried out at the following temperatures (K): 298; 308; 318 and 333.The concentration of I and II was (g/L) 0.05% 0.1 and 0.15.It was found that at a temperature of 298 K and concentration 0.05 g/L, the degree of corrosion protection is ~88.5% (compound I) and 76.0% (compound II).With an increase in their concentration to 0.15 g/L, their inhibitory properties increase and at a temperature of 298 K they are 97.2 and 92.8%, respectively.However, with an increase in temperature to 333 K, the maximum degree of corrosion protection is ~79% (compound I) and 70 (compound II), at their concentration of 0.15 g/L.Based on the obtained results, a blocking, chemisorption mechanism of protection of the surface of steel St.3 from corrosion by the tested compounds containing in the aromatic ring along with allyl, isododecyl and hydroxyl groups, also a bulky amine cation and chloride anion is proposed.High inhibitory properties of the studied practically non-volatile compounds are also confirmed by data on the areas of filling () with them, as well as by the calculated thermodynamic parameters of the adsorption processes (Gads, Nads, Sads).Negative values of Gads indicate spontaneous chemisorption on the metal surface