دانلود رایگان مقاله انگلیسی اسید های آمینه و مشتقات آن به عنوان مهار کنندگان فلزات و آلیاژها - الزویر 2017

Abstract

In the last two decades, research in the field of corrosion inhibitors had been directed toward the goal of using cheap effective molecules of low or non-negative environmental impact to replace the environmentally hazardous compounds. One of the encourager compounds which can be used as safe corrosion inhibitors are amino acids. They are environmentally friendly, nontoxic, biodegradable and relatively cheap. On other hand, the development of computational modeling helps to understand the inhibition mechanism of those compounds and to develop the newly designed inhibitors. In this review, most of contribution made in literature on the use of amino acids and their derivatives as corrosion inhibitors for metallic alloys materials were presented and discussed.

5. Conclusion

A thorough examination of the available literature revealed that almost tested amino acids compounds have been exhibited a good ability to use it as the eco-friendly inhibitors against metal corrosion in different mediums. However, there is no a universal amino acid compound that is applicable to most of the metal/solution systems. Hence, the inhibition capability of those compounds was depended to their molecular structure, their concentration, corrosive medium, metallic surface nature and to other factors. Whereas, some amino acids can act as effectiveness corrosion inhibitors, but it can also show an opposite effect, which accelerates the corrosion process; all depend on the operating conditions.

Actually, the recent research axes in the using of amino acids as corrosion inhibitors, it is to synthesize the new derivatives with high corrosion inhibition efficiency than its corresponding simple compounds (i.e. amino acid), and explain their inhibition mechanism using quantum chemical calculation and/or simulation by molecular mechanic approach. In this context, the density functional theory (DFT) has been widely used to study these compounds alone (i.e. without interaction with a metal surface) regarding molecular mechanic simulation (based on classical mechanic) due to its readable and accurate results. Except that, the disadvantage of DFT methods is the time consumption and the limitation of studied system size. Especially, when the ‘‘inhibitor molecule-metal surface” system was considered. In other hands, there are a few works on the use of QSAR modeling with computational chemistry methods to design new amino acids derivatives to act as efficient corrosion inhibitors. For this propose, we invite Table A1 the researchers to devote more attention to this subject.