新型三氮唑化合物在H_2SO_4中对Q235钢的缓蚀作用

Corrosion Inhibition of Mild Steel in Dilute Sulfuric Add Solution by Novel Triazole Compound

钢材酸洗时添加缓蚀剂是一种有效、经济的防腐蚀方法,研究缓蚀剂对其作用机理,发展和完善缓蚀剂理论,已成为研究热点。通过失重试验、动电位极化曲线、交流阻抗谱测试及扫描电镜(SEM)方法研究了新型三氮唑化合物1-(4-氟基苯)-3-[4-(1,2,4-三氮唑-1-甲氧基)-苯]-丙烯缓蚀剂(FTPP)在0.5mol/L H2SO4溶液中对Q235钢的缓蚀作用。结果表明:FTPP对Q235钢的缓蚀效果与自身浓度有关,在0.5mol/LH2SO4中当其达到10-3mol/L时,缓蚀率高达92.8%,能同时抑制腐蚀的阴、阳极反应过程,它是一种混合型缓蚀剂;Q235钢的阻抗值随FTPP浓度增加而增大,FTPP在钢表面的吸附符合Langmuir等温式。

Weight-loss measurement, potentiodynamic polarization curve measurement, electrochemical impedance spectroscopic (EIS) measurement, and scanning electron microscopic (SEM) analysis were conducted to investigate the effect of a newly devel-oped triazole compound, 1 -(4-fluoro-phenyl) -3-j4-( [1,2,4] triazol-1 -ylmethoxy) -phenyl} -propenone ( FTPP) , as a corro-sion inhibitor, on the corrosion resistance of Q235 steel in 0. 5 mol/L H2SO4 at ambient temperature. It was found that the corro-sion inhibitor was able to effectively retard the corrosion of the steel in dilute sulfuric acid solution, and its corrosion inhibition efficiency was closely related to concentration. The best corrosion inhibition efficiency, as much as 92. 8%, was obtained at an in-hibitor concentration of 10-3 mol/L. At the same time, the corro-sion inhibitor was capable of suppressing both cathodic and anodic processes of the steel in sulfuric acid, behaving as a mixed type corrosion inhibitor. Besides, the resistance of the steel increased with increasing concentration of the inhibitor, and the adsorption of FTPP on the mild steel surface in 0.5 mol/L H2SO4 was found to follow the Langmuir isotherm model.