This work tested the ethanol extract of camphor tree Cinnamomum camphora bark (CTBEE) as a green corrosion inhibitor of low carbon steel (LCS) in 0.5 M H₂SO₄ with and without the synergistic effect of 4000 ppm NaCl or 800 ppm of KI. The corrosion protection of LCS was significantly increased in the presence of CTBEE-KI and CBWE-NaCl blends compared with CTBEE alone, according to data performed by electrochemical impedance spectroscopy (EIS) and electrochemical polarization (EP) analyses. The formation of a film by the blends blocks the LCS surface area, preventing corrosive gradients from reaching its surface. Inhibition efficiency (IE%) of 81% and 89% were obtained in the presence of 800 ppm CTBEE-4000 ppm NaCl and CTBEE-800 ppm KI, respectively, compared with IE of 65% in the presence of 800 ppm CTBEE only. A maximum IE% of 89% and 97% were reached after 72 h of immersion in the presence of CTBEE-NaCl and CTBEE-KI, respectively. Potentiodynamic experiments indicate that the blends act as mixed-type inhibitors. The inhibition efficiency of CTBEE, CTBEE-KI, and CTBEE-NaCl remained effectively high during the testing period of immersion time, which proved the excellent stability of CTBEE in the corrosive acidic media.

中文翻译：

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樟树皮提取物作为 LCS 的绿色缓蚀剂，在 0.5 M H2SO4 中具有和不具有盐效应

这项工作测试了樟树肉桂树皮的乙醇提取物（CTBEE）作为低碳钢（LCS）的绿色缓蚀剂在0.5 MH ₂ SO ₄中的作用，有或没有4000 ppm NaCl或800 ppm KI的协同作用。根据电化学阻抗谱 (EIS) 和电化学极化 (EP) 分析的数据，与单独使用 CTBEE 相比，在 CTBEE-KI 和 CBWE-NaCl 混合物存在下，LCS 的腐蚀防护能力显着增强。混合物形成的薄膜会阻挡 LCS 表面积，从而防止腐蚀梯度到达其表面。在 800 ppm CTBEE-4000 ppm NaCl 和 CTBEE-800 ppm KI 存在下，抑制效率 (IE%) 分别为 81% 和 89%，而仅在 800 ppm CTBEE 存在下，抑制效率 (IE%) 为 65%。在 CTBEE-NaCl 和 CTBEE-KI 存在下浸泡 72 小时后，最大 IE% 分别达到 89% 和 97%。动电位实验表明该混合物可作为混合型抑制剂。在浸泡时间的测试期间，CTBEE、CTBEE-KI和CTBEE-NaCl的缓蚀效率仍然保持较高的缓蚀效率，这证明了CTBEE在腐蚀性酸性介质中具有优异的稳定性。