盐酸介质中水杨醛缩氨基硫脲对碳钢的缓蚀作用

Inhibition of Mild Steel Corrosion in Hydrochloric Acid Solution by Salicylaldehyde Thiosemicarbazone

合成了新型席夫碱缓蚀剂:水杨醛缩氨基硫脲(ST),并考察了其在1 mol/L盐酸溶液中对碳钢的缓蚀性能。通过静态失重、动电位极化曲线、交流阻抗等技术手段研究缓蚀剂浓度对腐蚀速率及缓蚀效率的影响,阐明缓蚀作用机理。结果表明,ST在盐酸介质中对碳钢具有良好的缓蚀性能。随着缓蚀剂浓度的增加,缓蚀效率逐渐增大。ST的加入显著降低了自腐蚀电流密度,为抑制阴极反应为主的缓蚀剂。ST在碳钢表面的吸附符合Langmuir吸附模型,为物理吸附与化学吸附共同作用。

A Schiff base corrosion inhibitor named salicylaldehyde thiosemicarbazone （ST） was synthesized. The inhibition effect of ST on the mild steel （MS） in 1 mol/L HCl solution was investigated by mass loss measurements, potentiodynamic polarization and electrochemical impedance spectroscopy. Meanwhile, the surface morphology was observed by scanning electron microscopy. The results show that ST has an excellent inhibiting effect for Q235 steel in the HCI solution. ST acts as a good inhibitor, predominantly retarding with cathodic reaction through adsorption on a MS surface. The adsorption of ST on Q235 steel surface obeys the Langmuir adsorption isotherm.