Effects of organic inhibitors on corrosion of zinc in an aerated 0.5 M NaCl solution

Abstract

The effects of organic inhibitors on corrosion of zinc in an aerated 0.5 M NaCl solution were investigated by polarization measurements. The inhibitors were sodium benzoate (NaBz), sodium N-dodecanoylsarcosinate (NaDS), sodium S-octyl-3-thiopropionate (NaOTP), 8-quinolinol (8-QOH) and 1,2,3-benzotriazole (BTAH). These inhibitors formed precipitate films of Zn(II) salts or complexes on the zinc surface together with zinc hydroxide and oxide to prevent corrosion in the solution. High inhibition efficiencies of NaOTP were acquired at concentrations c=1×10 −6–3×10 −5 M, BTAH at c=1×10 −4–1×10 −3 M, 8-QOH at c=1×10 −3–3×10 −3 M and NaBz at c=3×10 −3–1×10 −2 M. Films formed on the zinc surface were analyzed by X-ray photoelectron and Fourier transform infrared reflection spectroscopies.