Synthesis of Corrosion Inhibitors Based on (Thio)Urea, Orthophosphoric Acid and Formaldehyde and Their Inhibition Efficiency

Authors

Abror Nomozov, Department of Chemical Technology, Termez Institute of Engineering and Technology, Termez 190111, UzbekistanFollow
Khasan Beknazarov, Doctor of Technical Sciences, Professor, Angreen University, Tashkent, 190111, UzbekistanFollow
Sakhomiddin Khodjamkulov, Department of Chemical Technology, Termez Institute of Engineering and Technology, Termez 190111, UzbekistanFollow
Zafar Misirov, Department of Chemical Technology, Termez Institute of Engineering and Technology, Termez 190111, UzbekistanFollow
Sarvinoz Yuldashova, Department of Chemical Technology, Termez Institute of Engineering and Technology, Termez 190111, Uzbekistan AND Department of Medical and Biological Chemistry, Termez branch of Tashkent Medical Academy, Termez, 190111, UzbekistanFollow

Abstract

In this article, the optimal conditions for the synthesis of two types of oligomeric corrosion inhibitors, polymethylene diamidophosphate (PDAF-1) and polymethylene thiodiamidophosphate (PTAF-2), based on compounds such as thiourea, urea, and orthophosphoric acid containing nitrogen and phosphorus, as well as their formulas, are determined. At first, (thio)diamidophosphate - PDAF-1 brand corrosion inhibitor was synthesized using urea and orthophosphoric acid in a 2:1 mol ratio at a temperature of 135–140°C. The second type of polymethylene thiodiamidophosphate (PTAF-2) corrosion inhibitor was synthesized based on the process of condensation in an aqueous environment at a temperature of 60°C, by adding formaldehyde to this obtained compound in a stoichiometric 1:1 mol ratio. The resulting substance is a white solid, non-volatile, the composition of the main component is 98.7%, and other substances - 1.3%. IR-spectra investigated the structure of these two types of corrosion inhibitors. Also, the inhibition efficiency of these corrosion inhibitors was studied by gravimetric and electrochemical methods in corrosive media such as HCl, H2SO4 and NaCl D 3%. In addition, the factors a ecting the inhibition efficiency, such as the pH of the solution, the duration of time, and the concentration of the inhibitor, were also studied. According to the obtained results, the inhibition efficiency of these corrosion inhibitors was between 95.3 and 97.8%. Also, electron microscopy studied and analysed the protection mechanism of corrosion inhibitors on the steel surface.

Keywords

Corrosion inhibitor, Dithioamidophosphates, Formaldehyde, Orthophosphoric acid, Polymethylene thiodiamidophosphate

First Page

458

Last Page

471

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Receive Date

1-3-2024

Revise Date

6-21-2024

Accept Date

6-23-2024

How to Cite this Article

Nomozov, Abror; Beknazarov, Khasan; Khodjamkulov, Sakhomiddin; Misirov, Zafar; and Yuldashova, Sarvinoz (2025) "Synthesis of Corrosion Inhibitors Based on (Thio)Urea, Orthophosphoric Acid and Formaldehyde and Their Inhibition Efficiency," Baghdad Science Journal: Vol. 22: Iss. 2, Article 10.
DOI: https://doi.org/10.21123/bsj.2024.10590