Model of destruction of montmorillonite crystal structure in a microwave field

TL;DR

This study models the amorphization process of montmorillonite under microwave treatment, revealing a four-stage mechanism with specific energy consumption patterns and activation energies for different chemical bonds.

Contribution

It introduces a new model describing the microwave-induced amorphization of montmorillonite, including energy stages and activation energies based on X-ray analysis.

Findings

Amorphization occurs in four distinct stages.

Energy consumption varies across stages, with the third stage consuming the majority.

Activation energies for covalent and ionic bonds were evaluated.

Abstract

We address amorphization of montmorillonite crystal structure. Powdered montmorillonite samples with an effective particle diameter 630 micrometers were treated by a microwave field with frequency 2,45 GHz and power 750 W for ten minutes in different environments. The first sample was treated in an air environment, the second one in a humid environment. The third sample was a ceramic mass with 10 percent concentration of mixing water (with respect to the total mass). The model describing amorphization is based on results of X-ray analysis. Activation energies were evaluated for covalent and ionic bounds of oxygen ions, hydroxyl groups, and silicon (aluminum) ions. It is shown that the amorphization is carried out in four stages. In fractions of the energy consumption of the last stage the first one consumes 7-9 percent, the second one takes 13-15 percent, and the third one takes 49-59 percent.