Quantum Descriptors and Corrosion Inhibition Potentials of Amodaquine and Nivaquine

Adejoro Ia,Akintayo Dc,Ibeji Cu

doi:10.4172/2150-3494.1000149

Adejoro Ia, Akintayo Dc + Show 1 more

Open Access

https://doi.org/10.4172/2150-3494.1000149

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Abstract

Amodaquine [4-[(7-chloroquinolin-4-yl) amino]-2-(diethylaminomethyl) phenol] and nivaquine (4-N-(7- chloroquinolin-4-yl)-1-N,1-N-diethylpentane-1,4-diamine sulphate) has been studied as potential source of green inhibitor for corrosion of aluminium in 1 M HCl at different concentrations using gravimetric method. To further elucidate the reactivity and efficiency of these anti-malaria drugs as potential corrosion inhibitors, quantum chemical calculations using Density Functional Theory (DFT) method in conjuction with Becke 3 Lee Yar Parr (B3LYP)/6-311++G** level of theory was applied. Kinetics and thermodynamic parameters central to surface adsorption were calculated and discussed. Results revealed that the inhibition efficiency increased as the inhibitor concentration increased but decrease with an increase in temperature with Nivaquine having better inhibition efficiency than Amodaquine. The adsorption of Amodaquine and Nivaquine on the surface of aluminium both followed the Freundlich adsorption isotherm at all concentrations and temperatures. The negative value of ΔGads obtained indicates spontaneous adsorption of the inhibitor on the aluminium surface and a low negativity indicates electrostatic interactions between inhibitor and the charged metal surface.

Highlights

Corrosion, a constant and continuous problem, is the deterioration of metal by chemical attack or reaction with its environment
When aluminium is exposed to aggressive environments such as acid pickling solutions, chemical etching, industrial cleaning or scale dissolving, these processes lead to significant mass loss of aluminium [3]
The decrease with the rise in temperature, indicate that at higher temperature, dissolution of aluminium predominates on the surface

Summary

Introduction

A constant and continuous problem, is the deterioration of metal by chemical attack or reaction with its environment. The gravimetric experiments were performed on a previously weighed aluminium coupon completely immersed in 50 ml of the test solution in an open beaker in absence and presence of different concentration of the inhibitors. Weight loss, the inhibition efficiency (% IE) of the inhibitor, degree of surface coverage (Ө) and corrosion rates (CR) were calculated using equations (1)-(3) respectively [9,10].

Results

Conclusion