Synthesis And Evaluation Of The Corrosion Inhibitiors By Schiff Base Surfactant

The corrosion of metals causes great waste of materials and great economic loss worldwide.Therefore,corrosion has aroused widespread concern in academia and industry.At present,adding corrosion inhibitor is still the main way to protect metal.Schiff base corrosion inhibitor is widely used in various industrial activities to prevent and control corrosion in industrial production because of its high efficiency.The new type of Schiff base surfactant inhibitor makes use of the special hydrophilic and hydrophobic groups in the surfactants to make the Schiff base molecules more easily adsorbed on the metal surface and to block the contact between the corrosion medium and the metal,so as to protect metal.In this paper,three new Schiff base surfactants(SBCSs)are synthesized,which are SBCS-8,SBCS-12 and SBCS-16 respectively.The corrosion inhibition performance and corrosion inhibition mechanism were studied by means of weightlessness and electrochemical method,combined with SEM and XPS analysis methods.Firstly,the corrosion inhibition effect of SBCBs on carbon steel in 1.0 mol/L hydrochloric acid system was studied.The results show that SBCBs is a mixed corrosion inhibitor with cathodic inhibition,and follows the mechanism of adsorption film formation to inhibit corrosion.The corrosion inhibition rate increases with the increase of inhibitor concentration and decreases with the increase of temperature.The corrosion inhibition performance decreases in the order of SBCS-16,SBCS-12 and SBCS-8,the corrosion inhibition rate of SBCBs is between 93.10%?96.35%at 150 ppm.And the adsorption of SBCBs on carbon steel surface accords with Langmuir isotherm.The value of ?Gads 0 indicates that the adsorption process is spontaneous,including physical adsorption and chemical adsorption.Secondly,the corrosion inhibition performance of SBCBs on stainless steel in 4.0 mol/L hydrochloric acid system was studied.The results showed that the corrosion inhibition rate of the three inhibitors increased with the increase of the concentration of the inhibitor,and their corrosion inhibition performance decreased in the order of SBCS-16,SBCS-12 and SBCS-8.The inhibition rates were 94.51%,90.43%and 87.42%respectively at 100 ppm.Their adsorption on the surface of stainless steel conforms to the Langmuir adsorption isotherm.The value of ?Gads 0 indicates that the adsorption process is spontaneous,including physical adsorption and chemical adsorption.