The inhibition effect of tween-60 on the corrosion of cold rolled steel (CRS) in 1.0—8.0 mol8226;L-1 hydrochloric acid was studied with the mass loss method and potentiodynamic polarization method.The results showed that tween-60 was a good inhibitor in 1.0 mol8226;L-1 HCl.Inhibition efficiency increased with increasing inhibitor concentration and the maximum inhibition efficiency was 91.2% at 30 ℃ even when inhibitor concentration is low. However

inhibition efficiency decreased with increasing hydrochloric acid concentration and temperature. Polarization curves showed that tween-60 was a mixed-type inhibitor in hydrochloric acid

and apparently inhibited iron’s cathodic reaction.The experimental data were treated with adsorption theory and kinetic equations.Both the thermodynamic and kinetic parameters could be obtained.The thermodynamic results showed that the adsorption of tween-60 on the cold rolled steel surface obeyed the Langmuir adsorption isotherm equation. Furthermore

the adsorption process was a spontaneous and exothermic process accompanied by a decrease in entropy.The kinetic results showed that the rate constant (k) decreased obviously after adding tween-60 in HCl solutions

while the kinetic reaction constant (B) increased.The values of both apparent activation energy (Ea) and pre-exponential factor (A) increased in inhibited hydrochloric acid solution.The inhibitive mechanism was mostly decided by the apparent activation energy.