Synthesis of alkynyl alcohol derivatives and its corrosion inhibition on N80 steel in 5 M HCl

Alkynyl alcohol derivatives (N-14) were synthesized by 2-chloromethyl pyridine, propargyl alcohol and bromotetradecane and the structure was confirmed by ¹H NMR, ¹³C NMR, MS and FTIR. The corrosion inhibition performance was evaluated by weight loss, Tafel polarization, EIS measurements and DFT quantum calculations. The results proved that N-14 effectively inhibited the acid corrosion of N80 steel. The corrosion inhibition of N-14 increased with its concentration and decreased with increasing temperature. A maximum of 99.56% inhibition efficiency was achieved using 5 × 10⁻⁵ mol/l of N-14 at 60°C. Thermodynamic parameters showed that the adsorption of N-14 on N80 steel is spontaneous and exothermic, conforming to Langmuir's adsorption. Electrochemical results showed that N-14 behaved as a mixed-type inhibitor. In addition, corrosion products produced on N80 steel surface were researched by SEM, XRD, UV and contact angle. At the same time, the corrosion inhibition mechanism was discussed.