Protective Efficiency of Water-Soluble Corrosion Inhibitors

Abstract

Introduction. As a result of damage to agricultural and forestry machines from corrosion, the costs of maintaining their performance are increasing. The use of water-soluble inhibitors can slow or halt the destructive process. However, many of the inhibitors have disadvantages, for example, flammability or toxicity. The purpose of this work is to study the protective effectiveness of aqueous solutions of boric acid ester and triethanolamine and to develop recommendations for their use for anticorrosive protection of agricultural and forestry machinery in long-term storage. Materials and Methods. Protective compositions were prepared by dissolving boric acid ester and triethanolamine in distilled and industrial water at room temperature. Aqueous solutions with a concentration of water-soluble inhibitors of 5–50 g/l (0.5–5 mass %) were used for research. The linear polarization resistance method was used to assess their protective efficiency. Solartron (UK) measuring complex was used for electrochemical studies. Accelerated corrosion tests were carried out on steel plates according to GOST 9.054-75 in the g-4 humidistat. The aftereffect of water-soluble corrosion inhibitors was evaluated by the residual film protective efficiency. Results. The influence of the concentration of the ester of boric acid and triethanolamine in aqueous solutions for their protective properties is studied. It was found that boric acid and triethanolamine slow the anode reaction. The analysis of the research results has showed that the corrosion rate of the steel electrode decreases with increasing the concentration of water-soluble inhibitor in process water. This decrease is the most noticeable when the concentration in the range of 10–50 g/l with an increase in the concentration in the solution of boric acid and triethanolamine to 50 g/l, their protective efficiency varies by 6–14 %. The optimal concentration of the inhibitor in the composition is obtained, which is 10 g/l during corrosion tests of steel plates, the protective efficiency of the solution with a concentration of 10 g/l of the water-soluble inhibitor was more than 70 %. In case of precipitation on the samples, the protective efficiency of the solutions decreased to 20–25 %. When tested in a closed unheated room on steel samples during the year there were no traces of corrosion. Conclusions. The study demonstrates that boric acid and triethanolamine is a watersoluble inhibitor of anodic corrosion. When the concentration of water-soluble inhibitor in process water increases, the corrosion rate of the steel electrode decreases. Optimum concentration of ester of boric acid and triethanolamine in the protective solution should be 10 g/l. For corrosion tests of steel plates, the shielding effectiveness of a solution of water- soluble inhibitor was more than 70 %. In the conditions of direct exposure to atmospheric precipitation on the samples of the protective efficiency of the solutions decreased to 20–25 %. When tested in a closed unheated room on steel samples there were no traces of corrosion during the year. Thus, the ester of boric acid and triethanolamine is effective to protect against atmospheric corrosion in a closed room. it Is recommended to apply it for protecting cars against corrosion at short-term storage on open platforms. The application field of water-soluble inhibitor when agricultural and forestry machines are retained for long-term storage is defined; combine stages of cleaning cars from pollution and preserving their surfaces for protection against corrosion are offered. The article will be useful to specialists in the field of protection of agricultural machinery from corrosion.

Increasing of Corrosion Resistance for Metal Products of Livestock Premises

“…Up to 25% of metal products malfunctions and damage which operating in atmospheric conditions occurs due to biological effect of aggressive media present on them. [10,11] In livestock premises the metal products damage scale from biological corrosion is often comparable to electrochemical corrosion, which necessitates the multifunctional corrosion inhibitors development that can significantly increase corrosion resistance of metal products surfaces, machinery and equipment from all the above-mentioned types of livestock production corrosion [12].…”

“…The following factors influence on chemical air environment composition of livestock premises: animals type in the premise, feeding methods, and manure removal and microclimate systems efficiency. [17,18] Due to increased humidity presence in livestock premises, the corrosion processes on metal products surface occur under an insignificant layer of water, which is formed on metal products surface as a result of ionic, adsorption, or capillary moisture condensation.…”

Prevention of corrosion fracture of agricultural equipment during storage

“…This solution suits for storing technological machines and equipment of small size and weight, while placing in the garage, for example, a combine harvester, will not allow to set additional levels above it. As it has already been mentioned above, agricultural machinery as well as others are stored in most cases in open areas where they are exposed to destructive effects of atmospheric factors [2]. During such storage, a thin film of moisture, caused by temperature changes during the day or precipitation, is often formed on the surface of machines.…”