Abstract

This work aims to investigate the possible use of the palm kernel cake powder (Elaeis guineensis Jacq.) as corrosion inhibitor for ASTM 1020 carbon steel in acidic media (0.5 mol L⁻¹ HCl). The investigation was carried out using electrochemical impedance spectroscopy (EIS), polarization curves, gravimetric technique and scanning vibrating electrode technique (SVET). Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were employed as chemical and surface characterization techniques, respectively. The results of the EIS and gravimetric tests showed that the substance acts as an effective corrosion inhibitor and inhibition efficiency (IE) increases according with the increase of the corrosion inhibitor concentration in the aggressive medium. The highest IE of 87% was obtained for the highest corrosion inhibitor concentration used (1.77 g/L). The polarization curves revealed a mixed inhibitor. The adsorption of the studied inhibitor on carbon steel surface obeyed Langmuir isotherm. The SVET measurements did not reveal anodic or cathodic activities in the substrate surface in the presence of the inhibitor, revealing that the corrosion inhibitor was able to block both reactions. FTIR analyses identified in the powder the presence of hydroxyl group, aromatic rings, nitrogen and oxygen in such groups as amines and oleaginous acid, which can be responsible for the inhibitory properties of the whole material. SEM analyses showed that the corrosion process was retarded when the inhibitor was added to electrolyte. The results indicate that the powder of palm kernel cake is promising for use as corrosion inhibition purpose for carbon steel in acidic media.

Graphic Abstract

摘要

这项工作旨在研究棕榈仁饼粉（Elaeis guineensis Jacq。）作为酸性介质（0.5 mol L ^-1的ASTM 1020碳钢的腐蚀抑制剂）的可能用途。 HCl）。使用电化学阻抗谱（EIS），极化曲线，重量技术和扫描振动电极技术（SVET）进行了研究。傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）分别用作化学和表面表征技术。EIS和重量测试的结果表明，该物质可作为有效的缓蚀剂，并且随着侵蚀性介质中缓蚀剂浓度的增加，缓蚀效率（IE）也会增加。对于所使用的最高腐蚀抑制剂浓度（1.77 g / L），可获得IE最高的87％。极化曲线显示混合抑制剂。研究的缓蚀剂在碳钢表面的吸附符合朗缪尔等温线。SVET测量没有发现在抑制剂存在下基材表面的阳极或阴极活性，这表明腐蚀抑制剂能够阻止两个反应。FTIR分析确定了粉末中存在的羟基，芳环，氮和氧（如胺和油酸），这可能是整个材料的抑制特性。SEM分析表明，当将抑制剂加入电解质中时，腐蚀过程被延迟。结果表明，棕榈仁饼粉有望作为酸性介质中碳钢的缓蚀剂。揭示了缓蚀剂能够阻止两个反应。FTIR分析确定了粉末中存在的羟基，芳环，氮和氧（如胺和油酸），这可能是整个材料的抑制特性。SEM分析表明，当将抑制剂加入电解质中时，腐蚀过程被延迟。结果表明，棕榈仁饼粉有望作为酸性介质中碳钢的缓蚀剂。揭示了缓蚀剂能够阻止两个反应。FTIR分析确定了粉末中存在的羟基，芳环，氮和氧（如胺和油酸），这可能是整个材料的抑制特性。SEM分析表明，当将抑制剂加入电解质中时，腐蚀过程被延迟。结果表明，棕榈仁饼粉有望作为酸性介质中碳钢的缓蚀剂。SEM分析表明，当将抑制剂加入电解质中时，腐蚀过程被延迟。结果表明，棕榈仁饼粉有望作为酸性介质中碳钢的缓蚀剂。SEM分析表明，当将抑制剂加入电解质中时，腐蚀过程被延迟。结果表明，棕榈仁饼粉有望作为酸性介质中碳钢的缓蚀剂。

图形摘要