Adsorption and thermodynamics properties of acacia tortilis as corrosion inhibitor of aluminum metal matrix composites in acidic medium

Metallurgical & Materials Engineering

article

Suleiman Idawu Yakubu¹  Rufai Ochu Suleiman²  Rasheed Agava³  Ogheneme Clifford⁴  Emokpaire Steven⁵ 

[1] Department of Metallurgical and Materials Engineering, University of Nigeria;Department of Chemistry, Ahmadu Bello University Zaria;National Agency for Science and Engineering Infrastructure;Department of Mechanical Engineering;Departmentof Metallurgical Engineering

关键词: Acacia tortilis;    Corrosion inhibition;    Gravimetric method;    Potentiodynamic polarization;    SEM/EDS.;   

DOI  :  10.30544/281

学科分类：医学（综合）

来源: Association of Metallurgical Engineers of Serbia

【 摘 要 】

Acacia tortilis (AT) was extracted and characterized by gas chromatography-mass spectrometry (GC-MS). The eco-friendly corrosion inhibitor for aluminum matrix composites was investigated in 1.0 M HCl at 30-60 °C. The concentration of the inhibitor and time were varied in the range of 0 – 10 % v/v and 24-144 h. The inhibition studies were carried out using gravimetric method and potentiodynamic polarization. The surface morphology of the coupons was characterized by SEM/EDS techniques. The GC-MS revealed some elements/compounds (NCS, C-H, N or O). The inhibition efficiency increased with concentration and decreased with increase in temperature. The optimum inhibition efficiency of 89.60% was obtained at concentration of 8% v/v at 30 °C. Potentiodynamic polarization confirmed that the inhibitor acts as mixed types inhibitor. Activation energy (Ea) with inhibitor was higher than without inhibitor and proved to be physisorption. The thermodynamic parameters (standard free energy ΔG°), standard enthalpy (ΔHads) and standard entropy (ΔS) of the adsorption process were calculated. The inhibition mechanism of AT extract on Al-Si-Fe/15%SiC was physical and obeyed Langmuir adsorption isotherm. The protective layer on the composite surface confirmed the potential of the extract as corrosion inhibitor. The results of weight loss were in good agreement with those of electrochemical technique.

【 授权许可】

CC BY