Chemical Control of Hydrodynamic Instabilities in Partially Miscible Two-Layer Systems.

Area of Science:

• Fluid dynamics
• Chemical engineering
• Geoscience

Background:

• Hydrodynamic instabilities at liquid-liquid interfaces are critical for applications like CO2 sequestration.
• Understanding these instabilities is key to optimizing processes involving partially miscible fluids.

Purpose of the Study:

• To introduce a novel laboratory-scale model system for studying buoyancy- and Marangoni-driven convective instabilities.
• To investigate the rich spectrum of convective dynamics in partially miscible two-layer systems.

Main Methods:

• Stratification of a pure alkyl formate on top of a denser aqueous solution under gravity.
• Inducing partial dissolution of the ester into water, followed by hydrolysis.
• Observing and analyzing the resulting convective dynamics and patterns.

Main Results:

• A diverse range of convective behaviors was observed.
• The miscibility of the ester, feedback effects on miscibility, and aqueous reactivity influenced the convective patterns.
• The system demonstrated sensitivity to chemical and physical properties at the interface.

Conclusions:

• The developed model system facilitates easy study of complex hydrodynamic instabilities.
• Control over convective patterns is achievable by manipulating miscibility and reactivity.
• This research provides insights into interfacial phenomena relevant to CO2 sequestration and other applications.