Oscillatory Briggs-Rauscher Reaction as “Fingerprint” for Bentonite Identification: The Fine-Tuning of Oscillatory Dynamics with Addition of Clay

Abstract

The oscillatory Briggs-Rauscher (BR) reaction was applied on solid insoluble materials i. e. bentonite clays. Under the same BR experimental conditions, the addition of identical masses of bentonite of different origin resulted in different effects on oscillatory time duration (τ): no influence, quenching, or prolongation. It was found that the following bentonite properties: montmorillonite/beidellite ratio; cation exchange capacity; principal exchange cation; extent of iron leaching in acidic environment of BR reaction; and specific surface area of clay were not exclusively responsible for observed behavior. On the other hand, the influence of added mass, for all investigated clays, resulted in the same behavior pattern. The increase of the mass of added clay increased τ up to the certain maximal value (τmax, mmax) characteristic for each clay. Further increase of mass resulted in quenching. Therefore, (τmax, mmax) pair can be regarded as the “fingerprint” characteristic of bentonite useful for identification of its origin. Furthermore, the addition of naturally occurring and non-toxic clay in an oscillatory reaction can offer a versatile approach to tune the oscillation dynamics of nonlinear chemical systems.