SYNTHESIS AND PROPERTIES OF NITROGEN-RETAINING CORROSION INHIBITORS

ABSTRACT

Today, the oil and gas industry is developing rapidly. Alternatively, there are problems that need to be solved in this area. The most relevant in problems is corrosion of metals. Because corrosion causes great damage to the economy of the country. It is much more important to synthesize new and effective corrosion inhibitors and determine their effects in a variety of aggressive environments. In this article, taking into account the above, the nitrogen-retaining corrosion inhibitor has been synthesized and the inhibitory properties have been studied.

АННОТАЦИЯ

Сегодня нефтегазовая отрасль стремительно развивается. С другой стороны, есть проблемы, которые необходимо решить в этой области. Наиболее актуальной в проблемах является коррозия металлов. Потому что коррозия наносит большой ущерб экономике страны. Гораздо важнее синтез новых эффективных ингибиторов коррозии и определение их действия в различных агрессивных средах. В данной статье с учетом изложенного синтезирован азотудерживающий ингибитор коррозии и изучены его ингибирующие свойства.

Keywords: corrosion inhibitor, monoethanolamine, concentrated methanal solution, diethanolamine, degree of protection, effectiveness.

Ключевые слова: ингибитор коррозии, моноэтаноламин, концентрированный раствор метанaла, диэтаноламин, степень защиты, эффективность.

INTRODUCTION. Corrosion inhibitors are chemical compounds, with a small amount of which also slows the corrosion rate of metals. The advantage of corrosion inhibitors over other methods of protection is its low consumption and access to any part of the corrosive environment. Mild steel alloys are one of the most commonly used construction materials for pipelines of the oil and gas industry. However, they are also very sensitive to high overall corrosion rates and local corrosion. Surface-active substances are widely used in the drilling, hydrocarbons extraction, transportation and processing of the oil industry to protect iron and steel devices. The major part of corrosion inhibitors in the oil and gas processing industry are complex organic compounds. Soluble corrosion inhibitors in water and hydrocarbons are most effective for use in the oil and gas industry. Because they have a high protective effect and easily interact with metals. The effectiveness of inhibitors depends on the concentration of the inhibitor and the time of interaction with the metal surface[1-5].

As you know, many organic compounds have an anti-corrosion effect. To do this, it is necessary to determine the link between their protective properties and their chemical structure. Huckerman studied the inhibitory properties of organic compounds and the link between their structure. Came to the conclusion that the protective properties of organic compounds are determined by the electron density of the atom, which is the center of the main reaction. Adsorption of corrosion inhibitor on the metal surface is characterized by an increase in the electron density in the reaction center[6].

METHOD. The composition selected MEA and DEA as a source of nitrogen for obtaining nitrogen-retaining inhibitors. The chemical reaction was carried out in a three-stringed tube with a volume of 150 ml, equipped with a thermometer and a mixer. MEA and formalin were mixed in a 1:1,5 molar ratio in the tube. The reaction mixture is mixed without heating for 30 minutes, then the tube is connected to the Libix refrigerator and with the help of a water pump, a vacuum is formed and distillated. After this, adding 1 mole aryl vinyl ether is mixed for 14 hours at a temperature of 95-98°C. The resulting reaction mass is dissolved in benzene, after which the resulting benzene solution is washed 5-6 times with water. In this, the reaction yield is 91%. The brutto formula of the reaction product is C₁₃H₁₇O₃N.  During the process, the separated aqueous solution contains 15-22% monoethanolamine and methanol[7-10].

RESULTS. When condensing aryl vinyl ether with methanal and amines, the choice of nitrogen-retaining monoethanolamine and methanal is considered as a local raw material. The results showed that during the condensation of aryl vinyl ether with methanal and monoethanolamine, it is formed according to the following scheme:

The aminomethylation reaction of aryl vinyl ether`s occurs in the range of pH = 3-8. To achieve a high degree of conversion, it is necessary to use a large amount of aminomethylating agents. The resulting product is a yellow resin, soluble in water, soluble in organic solvents and acids. Synthesized corrosion inhibitors were tested on the steel's St₂₀-brand. Steel 20 is a structural carbon steel of high quality, widely used in industry.

Table 1.

Chemical composition in % of the material St₂₀

The following results were obtained by testing the corrosion inhibitor at various concentrations over a specific temperature range. A 15% solution of hydrochloric and sulfuric acids was used to create an acidic environment.

Table 2.

Effectiveness of steel acid corrosion inhibitors

The following results were obtained when the synthesized corrosion inhibitor was used at different concentrations at room temperature.

         Figure 1. Dependence of steel corrosion degree of protection on AMKI concentration

As a result, when the inhibitor concentration was 0,1%, the degree of protection was 92,3%.

ACKNOWLEDGEMENT. We thank to the Ministry of Higher and Secondary Specialized Education of the Republic of Uzbekistan and Bukhara Engineering Technological Institute.

DISCUSSION. NGH (RH) 39.0-051:2007 according to paragraph 5.4 of the state standard, the protective ability of corrosion inhibitors should not be less than 90% for water-oil emulsions, not less than 80% for the aqueous part of the water-oil environment.

AMKI corrosion inhibitor document complies with the requirements of NGH (RH)39.0-051:2007, their protective ability in water-oil emulsion with a concentration of 500 g/ml was 90,2-93,5%. The results obtained show the prospects of research on the development of corrosion inhibitors.

References:

1. Назаров Шомурод, Ахмедов Вохид, Олимов Бобир, Ҳаитов Садулло синтез мономеров при участии винилацетилена из одноатомных фенолов содержащих ариловую группу // Universum: химия и биология. 2020. №11-2 (77). URL: https://cyberleninka.ru/article/n/sintez-monomerov-pri-uchastii-vinilatsetilena-iz-odnoatomnyh-fenolov-soderzhaschih-arilovuyu-gruppu (дата обращения: 16.04.2021).
2. Olimov, B., & Akhmedov, V. (2020). The effect of reaction duration and catalyst on the synthesis of arylvinyl esters. Збірник наукових праць ΛΌГOΣ, 33-37. https://doi.org/10.36074/20.11.2020.v2.07
3. Bahodirovich, Olimov B., et al. "Synthesis of  Resorcinol Vinyl Ether in the Mono-position, Influence of the Catalyst, Temperature and Solvent on the Reaction Yield." JournalNX, 2020, pp. 44-51.
4. Б.Б. Олимов, В.Н. Ахмедов, Ш.К. Назаров. Электронная структура и квантово-химические расчёты виниловых эфиров фенолов. U55 Universum: химия и биология: научный журнал. – № 4(70). М., Изд. «МЦНО», 2020. – 53-57с.
5. B.B. Olimov, V.N. Ahmedov, S. Hayitov.  Ikki atomli fenollar asosida vinilli efirlarni olish usullari. Fan va texnologiyаlar taraqqiyoti ilmiy – texnikaviy  jurnal. - № 1/2020.
6. Б.Б. Олимов, В.Н. Ахмедов. Винилацетилен асосида фенолларнинг винил эфирлари синтези. “Замонавий ишлаб чикаришнинг мухандислик ва технологик муаммоларини инновацион ечимлари” Халкаро илмий анжуман материаллари Бухоро. 2019. 37-39 б.
7. Олимов Б.Б., Гафурова Г.А., Кудратов О.Х. Production and properties of corrosion inhibitors in the oil and gas industry // Universum: химия и биология: электрон. научн. журн. 2022. 2(92). URL: https://7universum.com/ru/nature/archive/item/13009
8. Olimov B.B., Akhmedov V.N., Gafurova G.A., Application of derivatives of diatomic phenols as corrosion inhibitors. Euro Asian Conference on Analytical Research (Germany) ISBN: 978-1-913482-99-2. 2021. 15 October. p. 136-138.
9. Olimov B., Akhmedov V., Gafurova G. Production and use of corrosion inhibitors on the basis of two-atomic phenols and local raw materials // Universum: химия и биология : электрон. научн. журн. 2021. 11(89). URL: https://7universum.com/ru/nature/archive/item/12473
10. Olimov B.B., Sadiqova M.I., Beshimov I.A. Technology of obtaining effective corrosion inhibitors in the oil and gas industry // Universum: технические науки: электрон. научн. журн. 2022. 1(94). URL: https://7universum.com/ru/tech/archive/item/12950