硫酸介质中桂花果提取液对Q235钢的缓蚀作用

目的研究在0.5 mol/L硫酸溶液介质中,桂花果提取液(OFFE)对Q235钢的缓蚀作用及机理。方法通过失重法和极化曲线、电化学阻抗谱等电化学方法研究了桂花果提取液对Q235钢在0.5 mol/L硫酸溶液介质中的缓蚀性能,考察了25℃下桂花果提取液浓度对缓蚀效率的影响,并对缓蚀机理进行了探讨。结果以95%的乙醇为溶剂浸提制备的桂花果提取液在0.5 mol/L硫酸介质中对Q235钢具有良好的缓蚀性能,缓蚀效率随其质量浓度的增加而增大,当其浓度达到10 g/L时,其缓蚀效率可达91.48%。电化学测试结果表明,桂花果提取液为混合型缓蚀剂,主要通过抑制阴极析氢过程来减缓Q235钢的腐蚀,缓蚀机理为"几何覆盖效应",其有效缓蚀成分在Q235钢表面的吸附符合Langmuir等温式,吸附平衡常数为1.09 L/g。结论在0.5 mol/L的硫酸介质中,桂花果提取液对Q235钢具有明显的缓蚀作用,是一种有广泛应用前景的天然绿色缓蚀剂。

Corrosion Inhibition Effect of Osmanthus Fragrans Fruit Extract in 0.5M H2SO4 Medium on Q235 Steel

The work aims to study corrosion inhibition effect and mechanism of osmanthus fragrans fruit extract on Q235 steel in 0.5 mol/L sulphuric acid solution medium. The inhibition performance of osmanthus fragrans fruit extract to Q235 steel in 0.5 mol/L sulphuric acid solution medium was studied in electrochemical methods including weight loss method, polarization curves and electrochemical impedance spectroscopy (EIS). Effects of osmanthus fragrans fruit extract concentration on inhibi-tion efficiency at 25℃ were investigated extract. The inhibition mechanism extract was discussed as well. The osmanthus fra-grans fruit extract prepared with 95% alcohol as extractive solvent exhibited excellent corrosion inhibition effect on Q235 steel in 0.5 mol/L sulphuric acid solution medium. The inhibition efficiency increased as the concentration of osmanthus fragrans fruits extract increased, and the inhibition efficiency was up to 92.90% when the concentration of osmanthus fragrans fruit ex-tract was 10 g/L. Electrochemical test results showed that the osmanthus fragrans fruits extract was a mixed-type inhibitor which inhibited corrosion of Q235 steel mainly by inhibiting hydrogen evolution process on the cathode, and the inhibition mechanism belonged to geometric blocking effect. The adsorption of effective inhibition part on the Q235 steel surface accorded with the Langmuir isothermal equation, and the adsorption equilibrium constant was 1.09 L/g.The osmanthus fragrans fruits extractis a natural and green corrosion inhibitor having wide application prospect, which has significant corrosion inhibition effect on Q235 steel in 0.5 mol/L sulphuric acid solution medium.