Organo-tin compounds as corrosion inhibitor for nickel in acetic acid solution

Corrosion studies were performed using polarization measurement in different compositions of acetic acid at 30 degrees C. The polarization curves for nickel showed active-passive and transpassive behaviour in the entire composition range of water-acetic acid solutions. Anodic dissolution of nickel in acetic acid solutions is markedly decreased with an increase in the acid concentration. In order to prevent the corrosion of nickel in acetic acid solution (20 mol%) some organo-tin compounds dibutyl tindichloride (Bu(2)SnCl(2)), phenyl tintrichloride (PhSnCl(3)), diphenyl tindichloride (Ph(2)SnCl(2)) and triphenyl tinchloride (Ph(3)SnCl) have been used as inhibitors, and their inhibition efficiency and surface coverage were evaluated. Triphenyl tinchloride (Ph(3)SnCl) gave the highest inhibition efficiency and all the inhibitors are held on the surface most probably by physical adsorption.