Alkaline Activation of Bentonite

Masharipova Zulfira; Dilshod  Khaydarov; Kamolbek  Masharipov; Azamat  Kenjayev; Ikromjon  Mamadoliev; Rasul  Eshmetov; Aziza  Abdikamalova; Shakhnoza  Kuldasheva; Mirtokhir  Muratov

doi:10.51699/cajmns.v7i2.3109

Authors

Masharipova Zulfira Laboratory of Colloid chemistry and industrial ecology, Institute of General and Inorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Toshkent, 100170, Uzbekistan
Dilshod Khaydarov Mamun University, Uzbekistan
Kamolbek Masharipov Head of the Department of Medical and Biological Chemistry, Profi University, Tashkent, Uzbekistan
Azamat Kenjayev Associate Professor, Chemistry Department, Samarkand Branch, Tashkent International University
Ikromjon Mamadoliev Vice-Rector for Research and Innovation, Termez Pedagogical Institute, Uzbekistan
Rasul Eshmetov Tashkent University, Uzbekistan
Aziza Abdikamalova Tashkent University, Uzbekistan
Shakhnoza Kuldasheva Tashkent University, Uzbekistan
Mirtokhir Muratov Tashkent University, Uzbekistan

DOI:

https://doi.org/10.51699/cajmns.v7i2.3109

Keywords:

Bentonite, Montmorillonite, Alkaline Activation, Sodium Carbonate, Sodium Form, Cation Exchange Capacity, Treatment Temperature, Treatment Time, Plasticity, Suspension pH

Abstract

The results of alkaline activation of natural bentonite from the Logonsky deposit using a 2 wt.% sodium carbonate solution with variation of treatment temperature and duration are presented. The effect of activation conditions on the cation exchange capacity, as well as on the technological properties of the material (moisture content, plasticity number, and pH of a 5 wt.% suspension), was evaluated. It is shown that increasing the temperature to 60 °C leads to an increase in cation exchange capacity, reaching a maximum at a treatment time of 3–5 h, which is associated with intensification of Ca²⁺/Na⁺ exchange in the interlayer positions of montmorillonite. A further increase in temperature to 70–80 °C is accompanied by a decrease in cation exchange capacity, probably due to partial structural changes and a reduction in the fraction of active exchange sites. An optimal activation regime providing high cation exchange capacity while maintaining satisfactory technological properties of the material was established.

References

Mukasa-Tebandeke, I. Z.; Ssebuwufu, P. J. M.; Schumann, A.; et al. Upgrading and characterization of smectite from selected volcanic sediments of Eastern Uganda. International Journal of Mineral Processing. 2015, 141, pp. 88–94.

Murray, H. H. Applied Clay Mineralogy: Occurrences, Processing and Applications of Kaolins, Bentonites, Palygorskite-Sepiolite, and Common Clays. Elsevier, 2007. 180 p.

Guggenheim, S.; Martin, R. T. Definition of smectite clay minerals. Clays and Clay Minerals. 1995, 43(2), pp. 255–256.

Mermut, A. R.; Lagaly, G. Baseline studies of the Clay Minerals Society source clays: layer-charge determination and characteristics of those minerals. Clays and Clay Minerals. 2001, 49(5), pp. 393–398.

Moore, D. M.; Reynolds, R. C. X-ray Diffraction and the Identification and Analysis of Clay Minerals. Oxford University Press, 1997. 378 p.

Eberl, D. D.; Drits, V. A.; Srodon, J. Deducing growth mechanisms for minerals from the shapes of crystal size distributions. American Journal of Science. 1998, 298(6), pp. 499–533.

Keller, W. D. Surface area, porosity, and adsorption properties of clays. Clays and Clay Minerals. 1955, 4(1), pp. 23–25.

van Olphen, H. An Introduction to Clay Colloid Chemistry. Wiley, 1977. 318 p.

Cohen, J. M.; Mercer, P. F. Adsorption characteristics of bentonite clay and their relation to surface properties. Surface and Colloid Science. 1992, 10(3), pp. 201–215.

Murray, H. H.; Bundy, W. M.; Harvey, C. C. Kaolin, bentonite, and silica sand deposits in the United States: a review. Applied Clay Science. 2000, 18(1–2), pp. 111–124.

Paterson, D. M.; Hagerty, R. Bentonite clay and its industrial applications. Industrial Minerals. 2008, 23(4), pp. 11–19.

Churchman, G. J.; Carr, R. M. The definition and assessment of clay materials for industrial applications. Applied Clay Science. 2013, 84, pp. 76–82.