Synergistic Inhibition Effect Of 2-MBI And SDBS Studied By Experiment And Molecular Dynamics Simulation

The phenomenon of corrosion exists widely in industry.Applying corrosion inhibitor is an economical and efficient method to solve this problem.And the synergistic effect is introduced into this field to improve the inhibition efficiency of inhibitors.Many achievements have been obtained.However,by now,the detailed synergistic adsorption behaviors of two inhibitors on metal surface is unclear suffered from the analytical techniques.In this thesis,the inhibition efficiency of 2-MBI and SDBS for P110 steel in 0.5 M H2SO4 is initially studied by experimental method,and then the detailed adsorption behaviors are unveiled by molecular dynamics simulation when they are applied singly and mixed with each other,respectively.Finally,the synergistic mechanism is unveiled.The experimental results show that the inhibition efficiency of both 2-MBI and SDBS initially increases with the increase of their concentration.However,when their concentration is rather high,the inhibition efficiency of 2-MBI changes little with increasing inhibitor concentration,while the inhibition efficiency of SDBS decreases.The adsorption isotherms indicate that both of these two inhibitors adsorb onto metal surface in form of multilayers.When adding SDBS into 2mM 2-MBI solution,the synergism parameter is found larger than 1,indicating existence of synergistic effect.The result of molecular dynamics simulation accords well with experimental results.When these two inhibitors are applied alone,each of them can adsorb onto the metal surface.When they are added together with each other,2-MBI adsorbs onto metal surface preferentially,inducing the charge of metal surface changing into electropositive.As a result,SDBS is attracted onto the metal surface with adsorbed 2-MBI in advance,which increase the density and thickness of inhibitor film,leading to higher inhibition efficiency.