Abstract: Corrosion inhibition performance for Q235 steel in acidic medium with chitosan and chitosan/cetyltrimethylammonium bromide (CTAB) blend system was studied with three methods (weight loss,potentio-dynamic polarization and electrochemical ac-impedance spectroscopy (EIS)).Results indicated that the inhibition efficiency is good that achieves 85% when the chitosan with mass concentration of 0.1 g/L is used as inhibitor alone and under conditions of corrosion medium,1.0 mol/L HCl;temperature,30 ℃ for 24 h.After addition of CTAB,the corrosion efficiency is significantly enhanced.When the mass fraction of CTAB is 10%,the inhibition efficiency reaches 92% and even higher.Both chitosan and CTAB show the corrosion inhibition performance.Their surface adsorption mechanism is different.However,when they are blended together,there is synergic effect and the corrosion inhibition efficiency is enhanced.

Key words: cetyltrimethylammonium bromide, chitosan, corrosion inhibitor, Q235 steel