AP23489432 – New conversion anticorrosive coatings based on manganese ore enrichment wastes of Kazakhstan
Objective of the project – Development of new technological solutions for processing manganese ore concentration waste from Kazakhstan deposits into phosphating solutions and conversion anticorrosive coatings.
Relevance: The problem of mining waste recycling is relevant not only for Kazakhstan but also for other countries. Millions of tons of minerals are extracted annually in the Republic, a significant portion of which is not utilized but accumulated, occupying large areas and polluting the environment. These wastes are technogenic mineral formations that can be used to produce phosphating solutions for forming anticorrosion coatings on steel structures and pipelines. The proposed development is distinguished by the use of manganese ore beneficiation waste from Kazakhstan as raw material for producing conversion coatings. The theoretical basis of the project is formed by studies of domestic and foreign scientists in the field of anticorrosion coatings based on industrial waste. The project includes experimental investigation of the chemical and mineral composition of the waste, the conditions for leaching manganese phosphates, and the parameters for coating formation. It also considers optimization of phosphating formulations and technologies to improve process efficiency. The expected results will expand the raw material base, enhance the competitiveness of research, and lead to the creation of new intellectual property protected by patents.
Scientific supervisor: Candidate of technical sciences, Associate Professor, Sholpan Kubekova
Expected and achieved results: The material and mineral composition of manganese ore beneficiation waste from the Zhairem and Borly deposits was studied using modern physicochemical analysis methods (XRF, IR spectroscopy, electron probe analysis), while the elemental composition was additionally determined using a Rigaku NEX CG II spectrometer. The selected samples were used to investigate the conditions for leaching manganese phosphates depending on phosphoric acid concentration (10–40%), solid-to-liquid ratio (1:5–1:100), temperature (20–75 °C), and process duration (1–6 hours). The influence of formulation and technological parameters of phosphating on the microstructure and corrosion resistance of conversion manganese phosphate coatings was studied. It was established that the optimal conditions for obtaining phosphating solutions are 10% H₃PO₄, a solid-to-liquid ratio of 1:25, room temperature, and a leaching time of 120 minutes, while the optimal phosphating parameters for carbon steel (St3) are 85 °C and 60 minutes. Under these conditions, the corrosion resistance of the coatings reaches 318±5 seconds, which is 1.5 times higher than that of coatings formed in a solution based on the commercial Mazhef salt. Electrochemical studies showed that the protection efficiency of coatings based on waste from the Altyn-Shoko deposit reaches 91.4%, for Zhairem — 58.3%, while for the Mazhef-based solution it does not exceed 30.6%. Electrochemical impedance spectroscopy confirmed an increase in charge transfer resistance up to 2348 Ω for coatings based on waste, compared to 2037 Ω for Mazhef coatings and 1532 Ω for uncoated samples. It was found that the obtained coatings have a dense crystalline structure, a uniform composition (Fe, Ca, Mn, P), and a thickness of 11.11±14.14 μm, which significantly exceeds the characteristics of coatings formed in Mazhef solutions. Gravimetric studies showed that the mass loss of coatings based on waste is 30% lower during the first 4 days and remains almost unchanged after 8 days, indicating high stability in aqueous environments. As a result of the project, 2 articles were published in international journals (Q1–Q3, WoS/Scopus), 1 article in a national journal, as well as a publication by Kubekova et al. (2025) with a high percentile (98), confirming the scientific novelty and practical significance of the results.
List of publications with links to them
- Kubekova Sh.N., Kapralova V.I., Raimbekova A.S., Dalbanbay A., Kuli Zh., Ibragimov A.B., Mukhanov A. Phosphating of carbon steel in solutions based on technogenic raw materials // ES Materials and Manufacturing. – 2025. – Vol. 30. – P. 1765. – DOI: https://doi.org/10.30919/mm1765
- Kubekova Sh.N., Kapralova V.I., Raimbekova A.S., Motovilov I.Yu., Ibraimova G.T., Ihsan N.A., Kuznetsov V.E. Investigation of possibility of manganese ore concentration wastes involvement in inorganic materials production // Chemical Journal of Kazakhstan. – 2024. – Vol. 4, No. 88. – P. 46–56. – DOI: https://doi.org/10.51580/2024-4.2710-1185.47