A series of tested surfactant compounds, namely, polyethylene glycol
tertiary octyl phenyl ether, Merck; triton X- 114, triton X- 100, and triton
X- 405 were investigated as inhibitors for corrosion of oil tanks steel in
HCl. It was found that the three used surfactants act as good inhibitors for
acid corrosion of the tested C-steel. The inhibition efficiency increases
with increased surfactant concentration as well as the number of ethylene
oxide units per molecule. Moreover, the inhibition efficiency decreases as
the temperature was increased. The adsorption of surfactants on steel
surface is a spontaneous process and follows Langmuir adsorption
isotherm.