色氨酸复配缓蚀剂对碳钢在硫酸中的缓蚀性能

The Corrosion Inhibition of Tryptophan and Its Compound for Carbon Steel in H_2SO_4 Solution

利用失重法、电化学法研究色氨酸及其复配缓蚀剂对Q235碳钢片在0.5mol/L硫酸介质中的缓蚀性能,并用吸附等温模型和腐蚀动力学对缓蚀机理进行初步探讨。结果表明:单独使用色氨酸的缓蚀率不高,L-色氨酸与碘化钾有一定的协同效应,而与抗坏血酸的协同效应不显著,将三者以最佳用量复配后,缓蚀率可达92.43%;色氨酸与抗坏血酸均为混合型缓蚀剂,而碘化钾和复配缓蚀剂均为阳极型缓蚀剂;色氨酸通过化学吸附的方式吸附于碳钢表面,符合Langmuir吸附等温式。

The tryptophan and its compound were tested as corrosion inhibitors for carbon steel Q235 in an aque-ous solution of 0.5 mol/L sulphuric acid by weight-loss and electrochemistry methods. The inhibitory mechanism was discussed by isothermal adsorption model and corrosion kinetics. The results show that single tryptophan has low corro-sion inhibitor effect, while L-tryptophan and potassium iodide have certain synergistic effect, but synergistic effect with ascorbic acid is not significant. The three optimum amount of compound, the inhibition efficiency reaches 92.43 % ; The L-tryptophan and ascorbic acid are mixed type inhibitors, whereas the potassium iodide and complex inhibitors are the anodic type; Tryptophan is absvrbed on the surface of carbon steel by chemisorption adsorbed, in line with the Langmuir adsorption isotherm.