Exponential modeling of Al₂O₃ reduction during activation of  Navbahor alkaline-earth bentonite

N.I. Boyjanov; G.M. Otajonova; B.B. Kendjayev; M.X. Matyakubova; N.K. Sabirova; A.T. Masharipov; I.R. Boyjanov; Q.P. Serkayev

doi:10.31643/2027/6445.44

Authors

N.I. Boyjanov Urgench State University named after Abu Rayhon Beruni
G.M. Otajonova Mamun University
B.B. Kendjayev Urgench Innovation University
M.X. Matyakubova Urgench State University named after Abu Rayhon Beruni
N.K. Sabirova Urgench State University named after Abu Rayhon Biruni
A.T. Masharipov Academic Lyceum of Urgench State University
I.R. Boyjanov Urgench State University named after Abu Rayhon Biruni
Q.P. Serkayev Tashkent Chemical-Technological Institute

DOI:

https://doi.org/10.31643/2027/6445.44

Keywords:

bentonite, acid, activation, relative area, modelling, exponential decay, coefficient of determination (R²).

Abstract

In this study, using mathematical modeling, the change in Al2O3 content as a function of acid concentration during hydrochloric acid activation of alkaline-earth bentonite from the Navbahor deposit is investigated. During the experiment, the HCl concentration varied from 5% to 20%, and the change in Al2O3 content was nonlinear. To describe the experimental data obtained during hydrochloric acid activation of alkaline-earth bentonite from the Navbahor deposit, an exponential decay model was proposed, and its parameters were estimated by regression analysis. The accuracy of this approach is supported by the coefficient of determination (R² = 0.964) and the root mean square error (RMSE = 0.231%), indicating high accuracy and stability. The results obtained show that the decrease in Al₂O₃ content under acid activation conditions exhibits a nonlinear dependence on hydrochloric acid concentration rather than on time, and they enable formulation of a mathematical expression for the quantitative description of the process and for evaluating the effect of concentration.

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Author Biographies

N.I. Boyjanov, Urgench State University named after Abu Rayhon Beruni

Doctor of Philosophy in Technical Sciences, Associate Professor at the Faculty of Chemical Technology, Urgench State University named after Abu Rayhon Beruni, 220100, H. Olimjon Street 14, Urgench, Uzbekistan. ORCID ID: https://orcid.org/0009-0002-1454-9478

G.M. Otajonova, Mamun University

Teacher at Mamun University, Khiva, Khorezm, Uzbekistan. ORCID ID: https://orcid.org/0009-0008-7529-9656

B.B. Kendjayev, Urgench Innovation University

Teacher, Urgench Innovation University, Khorezm region, Urgench, Uzbekistan. ORCID ID: https://orcid.org/0009-0002-3235-5159

M.X. Matyakubova, Urgench State University named after Abu Rayhon Beruni

Doctor of Philosophy in Technical Sciences, Associate Professor at the Faculty of Chemical Technology, Urgench State University named after Abu Rayhon Beruni, 220100, H. Olimjon Street 14, Urgench, Uzbekistan. ORCID ID: https://orcid.org/0009-0000-2961-3626

N.K. Sabirova, Urgench State University named after Abu Rayhon Biruni

Doctor of Philosophy in Technical Sciences, Associate Professor at the Faculty of Chemical Technology, Urgench State University named after Abu Rayhon Beruni, 220100, H. Olimjon Street 14, Urgench, Uzbekistan. ORCID ID: https://orcid.org/0000-0001-9685-9861

A.T. Masharipov, Academic Lyceum of Urgench State University

Doctor of Philosophy in Chemical Sciences, Teacher Academic Lyceum of Urgench State University, Fayozov 27, Urgench, Uzbekistan. ORCID ID: https://orcid.org/0009-0003-3537-3130

I.R. Boyjanov, Urgench State University named after Abu Rayhon Biruni

Candidate of Technical Sciences, Associate Professor of the Faculty of Chemical Technology, Urgench State University named after Abu Rayhon Beruni, 220100, H. Olimjon Street 14, Urgench, Uzbekistan. ORCID ID: https://orcid.org/0000-0002-8416-5472

Q.P. Serkayev, Tashkent Chemical-Technological Institute

Professor at the Tashkent Institute of Chemical Technology, Navoi Street, 32, Tashkent, Uzbekistan. ORCID ID: https://orcid.org/0009-0009-8316-4994

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