Corrosion inhibition by naphthylamine and phenylenediamine for the corrosion of copper-nickel alloy in hydrochloric acid

The effect of inhibitor concentration and temperature on the corrosion process of copper-nickel alloy in presence of naphthylamine (NA) and phenylenediamine (PDA) in 5% HCI has been investigated by weight loss technique. Maximum value of inhibitor efficiency was 85.6% for NA at 35 degrees C and 0.085 M inhibitor concentration, while the lower value was 1% at 55 degrees C and 0.01 M in the presence of PDA. Two mathematical models were used to represent the corrosion rate data: second order polynomial model and exponential model. Non-linear regression analysis shows that the first model was better than the second model with high correlation coefficient. (C) 2009 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.