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Updated: Apr 30, 2026
13:27
Exploring the Effects of Atmospheric Forcings on Evaporation: Experimental Integration of the Atmospheric Boundary Layer and Shallow Subsurface
Published on: June 8, 2015
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Propagating fronts and morphological instabilities in a precipitation reaction
Brigitta Dúzs1, István Lagzi, István Szalai
1Institute of Chemistry, Eötvös University , Budapest, Hungary.
Summary
Temporal oscillations and wave patterns in precipitation were observed in a gel reactor. These findings challenge standard Liesegang patterns and reveal complex structures in chemical reactions.
Area of Science:
- Chemical precipitation
- Pattern formation
- Reaction-diffusion systems
Background:
- Precipitation is crucial in biomineralization and geological formations.
- Standard Liesegang patterns arise from diffusion-driven precipitation.
- Understanding complex precipitation dynamics is key to various scientific fields.
Purpose of the Study:
- To investigate novel precipitation patterns in a two-side-fed gel reactor.
- To analyze temporal oscillations, wave formation, and morphological instabilities.
- To explore precipitation dynamics beyond traditional Liesegang patterns.
Main Methods:
- Utilizing a two-side-fed gel reactor with an Aluminum chloride (AlCl3)/Sodium hydroxide (NaOH) system.
- Observing temporal oscillations in precipitate mass and wave propagation.
- Employing simulations with a four-variable precipitation/redissolution model.
Main Results:
- Observed temporal oscillations in total precipitate mass.
- Documented propagating and annihilating waves in the precipitation layer.
- Identified morphological instabilities and lateral structure formation.
- Simulations qualitatively reproduced mass oscillations and revealed a 3D stratified precipitate structure.
Conclusions:
- The AlCl3/NaOH system exhibits complex precipitation dynamics, including oscillations and waves.
- These patterns form laterally at the interface of counterpropagating diffusion fronts.
- The study reveals a stratified 3D precipitate structure, offering new insights into reaction-diffusion systems.
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