The corrosion rate and interface capacity of steel in 0.5mol/L H 2SO 4+0 5mol/L Na 2SO 4 solution containing methyl red were measured by curve-fitting method of polarization data and Ac impedance technique at 20℃.The...The corrosion rate and interface capacity of steel in 0.5mol/L H 2SO 4+0 5mol/L Na 2SO 4 solution containing methyl red were measured by curve-fitting method of polarization data and Ac impedance technique at 20℃.The degree of coverage of methyl red on steel surface was calculated.The degree of coverage was found to increase with the increasing of concentration of methyl red.The experimental data were treated with adsorption kinetic theory,too.It was found that adsorption of methyl red on steel surface in the acidic solutions was a substitution adsorption process and one water molecule was displaced by each adsorbed methyl molecule.The experimental result shows that at 20℃ the adsorption behavior follows the isotherm θ/ =1/55.5exp[27808-972 θ)/RT ].The ideal surface adsorption free energy was calculated.The interface capacity of steel decreases with the increasing of the degree of surface coverage in acidic solutions at 20℃.展开更多
文摘The corrosion rate and interface capacity of steel in 0.5mol/L H 2SO 4+0 5mol/L Na 2SO 4 solution containing methyl red were measured by curve-fitting method of polarization data and Ac impedance technique at 20℃.The degree of coverage of methyl red on steel surface was calculated.The degree of coverage was found to increase with the increasing of concentration of methyl red.The experimental data were treated with adsorption kinetic theory,too.It was found that adsorption of methyl red on steel surface in the acidic solutions was a substitution adsorption process and one water molecule was displaced by each adsorbed methyl molecule.The experimental result shows that at 20℃ the adsorption behavior follows the isotherm θ/ =1/55.5exp[27808-972 θ)/RT ].The ideal surface adsorption free energy was calculated.The interface capacity of steel decreases with the increasing of the degree of surface coverage in acidic solutions at 20℃.
