Study of the properties of ethanolamine and boric acid interaction products as volatile corrosion inhibitors used to protect ferrous and non-ferrous metals

Ethanolamine with boric acid can form various products, but there have not been any comprehensive studies on their properties as volatile corrosion inhibitors. The aim of thisstudy wasto synthesize products of interaction between ethanolamine and boric acid and to analyze anticorrosion properties of the obtained substances on ferrous and non-ferrous metals. To determine the composition and conditionsfor obtaining an inhibitor with high anticorrosion properties, the authors conducted experiments with a variable ratio of reagents and reaction temperature. As a result, they developed methodsfor obtaining volatile corrosion inhibitors. Four products were synthesized: ethanolamine and boric acid adduct, aminoethylborate, di(aminoethyl)borate and tri(aminoethyl) borate. The anticorrosion properties of the inhibitors were checked in accelerated tests. The evaluation of the protective ability was determined by gravimetric method, after which the corrosion rate, corrosion inhibition coefficient and degree of protection were calculated. Anticorrosive effect of volatile corrosion inhibitors wastested on specimen plates made of steel St3, copper M1 and alloys D16, L63. As a result of tests of the obtained inhibitors, di(aminoethyl)borate showed the best protective properties. Its maximum protective effect of 89.9% was observed on steel, the minimum one of 30.3% - on copper. The obtained results willsignificantly increase the degree of protection of ferrous and non-ferrous metal productsfrom corrosion during operation, transportation and storage while reducing the cost of their maintenance.