Corrosion Inhibition of Copper in Sulfuric Acid Using Different Surfactants

DOI : http://dx.doi.org/10.13005/msri/060128

Download this article as: 

Four commercial non-ionic surfactant compounds, namely Bixin, Zenthoxylum almauta, Echitamin, Nyctanthin were tested as inhibition for corrosion of Copper 0.5 M sulphuric acid solution. Weight loss measurements, potentiostatic polarizatiors and cyclic voltammetry techniques were used in this study. It was found that all the four used compounds act as good inhibitors for acid corrosion of Copper. The inhibition efficiencies obtained by the three techniques were almost the same, and increases with increasing the surfactant concentration. The polarization studies show that all used compounds act also mixed inhibitors. The inhibition action of these surfactants is interpreted in view of their adsorption on the metal surface making a barrier to mass and charge transfer. It was found that the adsorption of compounds follows Longmuir isotherm. The values of free energy of adsorption for them were calcopperlated. It was found that the adsorption process is spontaneous and increases, for different surfactants, in the same direction as inhibition efficiency. The cyclic voltammetry shows that there is only one anodic peak corresponding to the dissolution reaction of electrode. The copperrrent of this dissolution peak was used also for corrosion rate measurements and in evaluation of inhibition efficiencies of the used compounds.

Corrosion Inhibition; Surfactant; copper and sulphuric acid