月桂酰缓蚀剂在柠檬酸介质中对Q235碳钢的缓蚀行为

Inhibition Behavior of Lauroyl Corrosion Inhibitor on Q235 Carbon Steel in Citric Acid Medium

采用失重法、电化学阻抗谱、极化曲线及量子化学计算研究了月桂酰两性基单乙酸钠在4.0%(质量分数,下同)柠檬酸溶液中对Q235碳钢的缓蚀行为。结果表明,月桂酰缓蚀剂具有较好的缓蚀效果,当其质量分数达到0.8%时,缓蚀率达到78.44%。电化学试验表明,该缓蚀剂在金属表面以吸附的形式形成一种覆盖膜,主要是以阳极抑制为主的混合型缓蚀剂。通过量子化学计算了缓蚀剂分子的LUMO、HOMO轨道能量,得出缓蚀剂羧基上的氧原子是吸附成膜的活性位点。

The corrosion behavior of sodium lauroamphoacetate corrosion inhibitor on Q235 carbon steel in 4. 0% citric acid solution was studied by weight-loss experiment, electrochemical impedance spectroscopy （EIS）, Tafel polarization curve and quantum chemistry calculation. Results show that the corrosion inhibitor has good effect on the corrosion of carbon steel, when the inhibitor mass fraction was 0. 8%, its inhibition efficiency reached 78. 44%. Electrochemical experiments show that the corrosion inhibitor is a kind of anodic type corrosion inhibitor, mainly as a form of adsorption on the metal surface to form a cladding. The LUMO and HOMO orbit energy were calculated by quantum chemistry calculation, the results show that corrosion inhibitor carboxyl O atom was adsorbed on the membrane of the active site.