Mathematical analysis of the linear increase in SiO₂ content during the activation of Navbakhor alkaline bentonite with hydrochloric acid

N.I. Boyjanov; U.B. Rakhimov; Z.M. Ataullaev; M.A. Boltayev; Q.P. Serkayev; M.O. Khamidova

doi:10.31643/2027/6445.33

Authors

N.I. Boyjanov Urgench State University named after Abu Rayhon Beruni
U.B. Rakhimov Urgench State University named after Abu Rayhon Beruni
Z.M. Ataullaev Urganch State Pedagogical Institute
M.A. Boltayev Tashkent Chemical-Technological Institute
Q.P. Serkayev Tashkent Chemical-Technological Institute
M.O. Khamidova Tashkent Chemical-Technological Institute

DOI:

https://doi.org/10.31643/2027/6445.33

Keywords:

bentonite clay, activation, sorption properties, mathematical modeling, linear model.

Abstract

In this study, the acid activation process of the bentonite clay, which was conducted for producing a bleaching sorbent for the oil and fat industry, was mathematically analyzed. Increase in SiO₂ content under different concentrations of HCl was analyzed using the different mathematical models. During acid activation, increasing the acid concentration from 5% to 20% resulted in an increase in the SiO₂ content from 61.94% to 65.12%. During the activation process, a moderate increase in HCl concentration caused the improvement of the sorption properties of the clay by dissolving some components and restructuring the active sites. An excessive increase in the concentration of HCl leads to degradation of the mineral structure and partial breakdown of the silica framework, which negatively influences sorption performance. Analysis of the obtained results using the different mathematical approaches showed that an increase in SiO₂ content during activation corresponds fully to a linear model. According to this, a linear model was described by the equation y = 60.785 + 0.2088·X. Accuracy of the results obtained from the linear equation was confirmed by a coefficient of determination, R² = 0.9845, indicating a high accordance with the experimental data. This model mathematically predicts the increase in SiO₂ content and proves that the activation process proceeds as a linear function. A mathematical approach to the activation process enables one to calculate in advance the properties of sorption of the clay, to reduce the consumption of acid and water, and to calculate the eventual demands of other reagents.

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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

U.B. Rakhimov, Urgench State University named after Abu Rayhon Beruni

Assistant, food technology, Urgench State University named after Abu Rayhan Biruni, 220100, Khamid Alimjan Street, 14, Urgench, Khorezm Region, Uzbekistan. ORCID ID: https://orcid.org/0000-0002-8704-6612

Z.M. Ataullaev, Urganch State Pedagogical Institute

Doctor of Philosophy (PhD) in Pedagogical Sciences, Associate Professor at the Department of Natural Sciences, Urgench State Pedagogical Institute, Uzbekistan. ORCID ID: https://orcid.org/0000-0002-6517-8163

M.A. Boltayev, Tashkent Chemical-Technological Institute

Doctoral candidate at the Tashkent Institute of Chemical Technology, Navoi Street, 32, Tashkent, Uzbekistan. ORCID ID: https://orcid.org/0000-0002-3172-658X

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

M.O. Khamidova, Tashkent Chemical-Technological Institute

Associate Professor at the Tashkent Institute of Chemical Technology, Navoi Street, 32, Tashkent, Uzbekistan. ORCID ID: https://orcid.org/0000-0002-7299-0395

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