EFFECT OF AMINO ACID COMPOUNDS IN INHIBITOR ON COPPER IN HCl SOLUTION

The corrosion inhibition action of benzotriazole(BTA),octanoyl glutamic acid,DL-threonine,DL-serine for copper in 0.5 mol/L HCl solution was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy.Coupon tests showed that the best inhibition efficiency reached 82.7% by using octanoyl glutamic acid with a concentration of 10-3 mol/L.According to the results of potentiodynamic polarization and electrochemical impedance spectroscopy,all these corrosion inhibitors under study suppressed cathodic corrosion reaction of copper,and the best corrosion inhibitor was octanoyl glutamic acid.The results also approved that the higher the concentration of octanoyl glutamic acid,the better the effect of inhibition,when the concentration of octanoyl glutamic acidwas between 10-5～10-3 mol/L.