Djamel Daoud

Experimental and theoretical study of a new synthesized Quinoline derivative as Greene inhibitor of corrosion for the cooling circuits in desalinated water

Quinoline and their derivatives extracted from biodiesel are often used for designing of many synthetic compounds with diverse pharmacological and medicinal proprieties. These kinds of compounds have a wide variety of applications in many fields. They serve as intermediates in certain enzymatic reactions and their use as environmentally safe corrosion inhibitors reveal their importance. The aim of this work is to investigate the corrosion inhibition of cooling circuits in desalinated water by new environment-friendly Quinoline Schiff base. This examination has been determined by potentiodynamic polarization and electrochemical impedance spectroscopy measurements. Results obtained of these methods consistently identify this compound as efficient inhibitor. Those corrosion parameters were determined from current-potential curves; it was found that corrosion rates decrease and percentage inhibition efficiency, surface coverage degree and polarization resistance increase with increasing additive concentration. Impedance measurements confirm these results where it was observed, that the effect of inhibitor addition appears by an increase in the charge transfer resistance and by a decrease in the capacity of interface. The results obtained from the Potentiodynamic polarization measurements are in good agreement with those obtained from the electrochemical method. Quantum chemical parameters are calculated using the Density Functional Theory method (DFT). Correlation between theoretical and experimental results is discussed.

1-{[4-(4-{[(2-Oxidonaphthalen-1-yl)methyl-idene]aza-nium-yl}phen-oxy)phen-yl]iminiumylmeth-yl}naphthalen-2-olate.

The title Schiff base compound, C34H24N2O3, was prepared by a condensation reaction of bifunctional aromatic diamine (4,4′-diaminodiphenyl ether) with hydroxynaphtaldehyde. The asymmetric unit contains two independent molecules with similar conformations. The compound contains a central oxygen bridge and two functionalized [(E)-(phenyliminio)methyl]naphthalen-2-olate units. The dihedral angles between the benzene rings linking to the central O atom are 74.64 (19) and 69.85 (18)° in the two independent molecules. Intramolecular O—H⋯O hydrogen bonding occurs between the protonated imino N atoms and deprotonated hydroxy O atoms in both molecules. In the crystal, weak C—H⋯O hydrogen bonds are observed.