Beloglazov G.S.,Federal Baltic University |
Beloglazov S.M.,Federal Baltic University
EUROCORR 2013 - European Corrosion Congress | Year: 2013
Data on efficiencies of morpholine derivatives against sulfide corrosion of mild steel were compared with results of pair correlation analysis of experimental and quantum chemical data. The 11 morpholines were studied as inhibitors of corrosion of mild steel in water salt media imitating sea water inoculated by sulfate reducing bacteria. The efficiencies of inhibitive anti-corrosion action (EICA) of the organic inhibitors (OIn) were determined. The positive values of the pair correlation coefficients between EICA and the net Mulliken charges on O and N* indicated that the best of the 11 OIn were those with less negative charges on O and N* atoms while the negative value of correlation between EICA and the net charge on S atom (varying from one OIn molecule to another) indicated that among the OIn studied, the ones with less positive charge on S atom were more efficient. Assuming that in accordance to Kupmans theorem, HOMO energy corresponded to the first ionization potential of a molecule while LUMO - to its electron affinity - within the studied row of OIn, there were neither pure donators nor pure acceptors.