Synthesis and Acidification Corrosion Inhibition Performance of a Novel Quinoline Quaternary Ammonium Salt - Phenacyl Quinoline Chloride (PCQ)

In this contribution, we present the preparation of a novel (firstly originated) corrosion inhibitor, i.e. phenacyl quinoline chloride (PCQ), and the comparative analyses upon the corrosion inhibition performances between PCQ and benzyl quinoline chloride (BQC, a commonly used corrosion inhibitor for acidizing). The PCQ was synthesized through the quaternarization reaction of quinoline, benzyl chloride and 2-chloroacetophenone under the condition of 75℃ and 20 h reflux, by using acetone as solvent and ethanol as recrystallizing agent. The chemical structures of PCQ and BQC were characterized by elemental analysis, NMR and IR. The corrosion inhibition performances of the two quaternary ammonium salts (use in isolation, use in combination with propargyl alcohol(PA), and use in combination with potassium iodide) were evaluated by static weight loss method in 15% hydrochloric acid at 90℃. Our experiments show that the inhibition efficiency of BQC and PCQ are 82.17% and 94.25%, respectively, under the adding amount of 1.00%. The inhibition efficiency of the combination of 0.50% PCQ+0.50% propargyl alcohol is 99.88%. The adsorption behaviors of BQC and PCQ on the surface of N80 steel coincide well with Langmuir adsorption isotherm. Moreover, the adsorption equilibrium constants kads of BQC and PCQ are 483.10 L/mol and 1 092.75 L/mol, respectively, and the Gibbs free energy change values are -30.77 kJ/mol and -33.24 kJ/mol with respect to BQC and PCQ, indicating the chemical-adsorption-dominated, also spon-taneous and exothermic adsorption processes of these two quaternary ammonium salts onto the N80 steel surface. © 2019, Materials Review Magazine. All right reserved.