Purpose

The purpose of this study was to investigate cimetidine as corrosion inhibitor of aluminium in hydrochloric acid medium.

Design/methodology/approach

Cimetidine was characterized by gas chromatography mass spectrophotometer and Fourier transform infrared spectroscopy to determine its chemical composition and functional groups, respectively. Gravimetric, potentiodynamic polarization and electrochemical impedance spectroscopic techniques were used in the corrosion inhibition process. Thermodynamic and adsorption parameters were evaluated. And response surface methodology was used to optimize the corrosion inhibition process.

Findings

Analysis of the results revealed that major constituents of cimetidine include metronidazole, n-hexadecanoic acid cyclohexane and methyl ester. It has C-H stretch, C = N stretch, CH₃C-H bend, ring C = C stretch, -C-O-O stretch, N-H bend, C-O stretch and C-H bend as predominant functional groups. Adsorption of molecules of the inhibitor on the aluminium surface was spontaneous, and it followed mechanism of physical adsorption. Response surface methodology revealed that quadratic model adequately described the inhibition efficiency of cimetidine as function of inhibitor concentration, temperature and time. Chemical and electrochemical results are in agreement that the cimetidine is a viable corrosion inhibitor. Cimetidine was revealed as mixed-type inhibitor because it controlled both cathodic and anodic reactions.

Originality/value

Empirical and optimization studies of cimetidine drug as corrosion inhibitor of aluminium in hydrochloric acid medium were carried out. The research results can provide the basis for deploying drugs (with mucosal protective and antacid properties) for corrosion control of metallic structures.

中文翻译：

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以西咪替丁为抑制剂对盐酸介质中铝的腐蚀抑制：经验和优化研究

目的

本研究的目的是研究西咪替丁在盐酸介质中作为铝的缓蚀剂的作用。

设计/方法/方法

西咪替丁通过气相色谱质谱仪和傅里叶变换红外光谱仪分别对其化学成分和官能团进行表征。在缓蚀过程中使用了重力、动电位极化和电化学阻抗光谱技术。评估了热力学和吸附参数。并采用响应面法优化缓蚀过程。

发现

结果分析表明，西咪替丁的主要成分包括甲硝唑、正十六烷酸环己烷和甲酯。它有 CH 拉伸，C = N 拉伸，CH ₃CH 弯曲、环 C = C 拉伸、-COO 拉伸、NH 弯曲、CO 拉伸和 CH 弯曲作为主要官能团。抑制剂分子在铝表面的吸附是自发的，并遵循物理吸附机制。响应面方法表明，二次模型充分描述了作为抑制剂浓度、温度和时间的函数的西咪替丁的抑制效率。化学和电化学结果一致认为西咪替丁是一种可行的腐蚀抑制剂。西咪替丁被揭示为混合型抑制剂，因为它控制阴极和阳极反应。

原创性/价值

对西咪替丁作为铝缓蚀剂在盐酸介质中的实验和优化研究。研究结果可为部署药物（具有粘膜保护和抗酸作用）用于金属结构腐蚀控制提供依据。