关键词:

改性木质素磺酸盐, 缓蚀机理, 电化学

Abstract:

The corrosion inhibition mechanism of modified lignosulfonate GCL2-D1 was studied by using methods of GPC, titration, differential UV-absorption spectrum, ESEM, EIS, etc.The results showed that the structure and corrosion inhibition properties of the lignosulfonate changed greatly after modification.The molecular weight changed from 11048 to 29381.The sulfonic content increased from 9.04% to 11.2%, and the carboxyl content increased from 5.81% to 15.84%.Through modification, the lignosulfonate extended itself in the solution from spherical shape to linear chains.When adsorbed on metal surface, the contents of S, Ca, and C had an obvious increase in the interfacial film, indicating the increase of adsorption points and adsorption amount of the modified lignosulfonate GCL2-D1.Electrochemical analysis demonstrated that GCL2-D1 belonged to mixed inhibitor.When the dosage of GCL2-D1 was 100 mg•L^-1, the charge transfer resistance increased from 564 Ω to 20680 Ω, and the interfacial capacity between metal and solution reduced distinctly from 2.84 mF to 0.041 mF.It indicated that the GCL2-D1 formed a compact film on the metal surface, resulting in inhibition of metal corrosion.

Key words:

改性木质素磺酸盐, 缓蚀机理, 电化学