Molecular Dynamics and Adsorption Behaviour of 2, 3- Diaminopyridine and 9, 10-Diaminophenanthrene In Neutral and Protonated Forms

International Journal of Research and Innovation in Applied Science (IJRIAS) | Volume VI, Issue V, May 2021|ISSN 2454-6194

Molecular Dynamics and Adsorption Behaviour of 2, 3- Diaminopyridine and 9, 10-Diaminophenanthrene In Neutral and Protonated Forms

K. E. Essien¹*, Okon, O. E², I. O. Ekpenyong³, and Effiong, James Okon^4
1Department of Chemistry, Akwa Ibom State University, P.M.B. 1167, Ikot Akpaden, Akwa Ibom State, Nigeria
²,³,⁴ Department of Science Technology, Akwa Ibom State Polytechnic, P.M.B. 1101, Ikot Osurua, Akwa Ibom State, Nigeria

Abstract: A computational studies on corrosion inhibition potential of 2,3- Diaminopyridine (DAP) and 9,10-Diaminophenanthrene (DAPN) were investigated using density functional theory (DFT) with RHF/STO-6G* method. Interesting results were obtained as the inhibition properties of these compounds correlated with molecular properties. With the aid of quantum chemical parameters such as EHOMO, ELUMO, energy gap, ionization energy, electron affinity, global hardness, global softness, global electrophilicity index, back donation and absolute electronegativity, the corrosion inhibition potentials were predicted. It was observed that the predictive corrosion inhibition potential of DAPN molecule is greater than that of DAP molcule. Nitrogen and carbon atoms were the sites of likely electrophilic attack as shown by high negative mulliken charges of these molecules. The binding sites of DAPN and DAP molecules on the surface of metal were further proven by molecular electrostatic potentials (MEPs).

Keywords: corrosion, inhibition, 2,3- Diaminopyridine, 9,10-Diaminophenanthrene, density

I.INTRODUCTION

Organic inhibitors are prevalence in industry for corrosion prevention of steel and its alloy. These may be due to their availability and eco-friendliness. Corrosion inhibition possesses advantages of economy, high-efficiency and facile-feasibility among other corrosion prevention measures, and has been widely applied in various fields such as petroleum extraction and refining, electric and power construction [1–3]. The large extent of interaction between the inhibitor and the metal surface prove the effectiveness of the inhibitor [4]. The metal surface is covered by a protective barrier against corrosive agent in the environment [5]. The aggressive acid solutions come in direct contact with metals during industrial processes such as metal removal and cleaning, acid descaling and oil well acidizing. In other to inhibit metal corrosion, corrosion inhibitors need to be added to an acid solution before using in any industrial process [6].

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