About the authors
| First name, Middle name, Last name, Scientific degree, Scientific rank, Current position. Full and brief name of the organization, The organization address. | Ilshat R. Sabirov, Postgraduate Student, Kazan State University of Architecture and Engineering, Kazan, Russian Federation Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it Nailya R. Rakhimova, Doctor of Technical Sciences, Professor, Kazan State University of Architecture and Engineering, Kazan, Russian Federation Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it , ORCID: 0000-0003-1735-1758 Vladimir P. Morozov, Doctor of Geological and Mineralogical Sciences, Professor, Kazan Federal University, Kazan, Russian Federation Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it , ORCID: 0000-0002-9713-2805 Alexey A. Eskin, Candidate of Geological and Mineralogical Sciences, Associate Professor, Kazan Federal University, Kazan, Russian Federation Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it , ORCID: 0000-0002-7133-2710 Elizaveta Yu. Ermilova, Candidate of Technical Sciences, Associate Professor, Kazan State University of Architecture and Engineering, Kazan, Russian Federation Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it , ORCID: 0000-0002-8091-4851 |
| Title of the article | The effect of thermal activation and grinding fineness on the reactivity of montmorillonite clays |
| Abstract. | Problem statement. In line with global trends in the modern development of the cement industry, one of the main ways to reduce the production and use of Portland cement clinker is the introduction of active mineral additives and/or mineral fillers into Portland cements. This has led to the need to expand the raw material base of the latter based on principles of prevalence and widespread availability, as well as the necessity to develop the theory and technology of new types of clinker-replacing materials. The aim of this work is to investigate the possibility of using montmorillonite clays of varying chemical-mineralogical and particle size composition as active mineral additives to Portland cement. Tasks: to study structural changes of montmorillonite clays during thermal activation using X-ray phase and thermal analysis methods; to investigate the influence of the chemical-mineralogical composition and particle size distribution of both raw and thermally activated montmorillonite clays on their pozzolanic activity, as well as on the properties of Portland cement fresh and hardened pastes. Results. The reactivity of montmorillonite clays depends not so much on the montmorillonite content as on the Al2O3 content in the raw clay, and increases after thermal activation with an increase in specific surface area. The montmorillonite content does not correlate with the Al2O3 content in the clay. The increase in reactivity of montmorillonite clays during thermal treatment occurs as a result of a decrease in the degree of crystallinity of clay minerals, partial destruction of their structure, and the formation of amorphous SiO2 and reactive Al2O3. Reducing the particle size of thermally treated montmorillonite clays from d90 – 59 to d90 – 50 increases their reactivity from 555–642 to 649–751 mg CaO/g, depending on the clay composition, as well as improving the strength characteristics of the mixed Portland cement hardened paste and the clinker replacement rate. Conclusions. The suitability of thermally activated montmorillonite clays with a clay mineral content of 49–70% and a particle size d90 of 50–60 for producing active mineral additives with an average pozzolanic activity of 555–751 mg CaO/g has been established. The possibility of effectively replacing up to 10% of Portland cement with thermally activated montmorillonite clays in blended binders under normal moisture curing conditions is demonstrated. |
| Keywords. | clay, montmorillonite, kaolinite, Portland cement, activity |
| For citations: | Sabirov I.R., Rakhimova N.R., Morozov V.P., Eskin A.A., Ermilova E.Yu., The effect of thermal activation and grinding fineness on the reactivity of montmorillonite clays// News of KSUAE, 2026, № 1 (75), p. 64-75, DOI: 10.48612/NewsKSUAE/75.6, EDN: FILRWX |
