Dent Maja, Fuchs-Godec Regina
Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia.
Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia.
Food Technol Biotechnol. 2021 Dec;59(4):413-421. doi: 10.17113/ftb.59.04.21.7026.
Due to the growing interest and attention of the world towards environmental problems and protection of environment, the worldwide demand for biodegradable and effective corrosion inhibitors for tinplate has grown. Considering the diversity of the structures of polyphenols that are present in sage extract, it represents a promising potential source of low-cost and effective biodegradable green corrosion inhibitor for tinplate in 3.0% sodium chloride solution which is evaluated in this study.
Tafel polarisation and electrochemical impedance spectroscopy (EIS) at 25 °C have been used to evaluate the inhibitory activity of sage ( L.) extract as a green inhibitor for the protection of tinplate from corrosion in 3.0% sodium chloride solution.
We used electrochemical impedance spectroscopy to show that sage extract could serve as an effective inhibitor (94.1%) of the corrosion of tinplate in 3.0% NaCl at a mass concentration of 0.2 mg/L and temperature of 25 °C. The results obtained from potentiodynamic polarisation reveal that the sage extract acts as a mixed type inhibitor, with inhibition efficiency up to 82.5%, and the inhibition efficiencies calculated from EIS are in close agreement with these results. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) results indicated that the inhibitory effect of the sage extract is due to the presence of a passivation layer on the tinplate surface, which consists of organic compounds such as polyphenols. These results confirm that the sage extract is more efficient in inhibiting the corrosion of tinplate at a concentration of 0.2 mg/L than at higher concentrations. Also, it shows good inhibition of tinplate in 3.0% sodium chloride solution.
The exceptional corrosion inhibition potential of sage extract opens a door for its use and revalorization as a green corrosion inhibitor in the food industry.
由于全球对环境问题和环境保护的兴趣与关注度不断提高，全球对马口铁可生物降解且有效的缓蚀剂的需求也在增长。考虑到鼠尾草提取物中多酚结构的多样性，它是一种很有潜力的低成本且有效的可生物降解绿色马口铁缓蚀剂来源，本研究对其在3.0%氯化钠溶液中的性能进行了评估。
采用25℃下的塔菲尔极化和电化学阻抗谱（EIS）来评估鼠尾草提取物作为绿色缓蚀剂对马口铁在3.0%氯化钠溶液中腐蚀的抑制活性。
我们通过电化学阻抗谱表明，在质量浓度为0.2mg/L、温度为25℃的条件下，鼠尾草提取物可作为马口铁在3.0%氯化钠溶液中腐蚀的有效缓蚀剂（缓蚀效率达94.1%）。动电位极化实验结果表明，鼠尾草提取物为混合型缓蚀剂，缓蚀效率高达82.5%，且由EIS计算得到的缓蚀效率与这些结果高度吻合。衰减全反射傅里叶变换红外光谱（ATR-FTIR）结果表明，鼠尾草提取物的缓蚀作用是由于马口铁表面存在由多酚等有机化合物组成的钝化膜。这些结果证实，鼠尾草提取物在浓度为0.2mg/L时比更高浓度时更能有效抑制马口铁的腐蚀。此外，它在3.0%氯化钠溶液中对马口铁也有良好的缓蚀效果。
鼠尾草提取物卓越的缓蚀潜力为其在食品工业中作为绿色缓蚀剂的应用和价值提升打开了一扇门。
