Insights on choline chloride-based deep eutectic solvent (reline) + primary alcohol mixtures: a molecular dynamics...

Area of Science:

• Green chemistry and sustainable solvents
• Materials science and molecular modeling

Background:

• Deep eutectic solvents (DESs) offer high stability, making them promising for industrial applications.
• Adding organic solvents to DESs can enhance their thermodynamic and transport properties.

Purpose of the Study:

• To investigate the thermophysical and transport properties of choline chloride-based DES (reline) mixed with primary alcohols.
• To understand the microscopic structural changes and hydrogen bond network dynamics at varying alcohol concentrations.

Main Methods:

• Molecular dynamics (MD) simulations were employed.
• Calculated properties include density, radial distribution function, coordination number, H-bond analysis, diffusion coefficients, and spatial distribution functions.

Main Results:

• Chloride ions preferentially interact with alcohol's hydroxyl groups, an effect strengthening with higher alcohol content.
• Hydrogen bonds between chloride ions and urea decrease with increasing alcohol concentration, especially beyond 0.4.
• Self-diffusion of choline, chloride ions, and urea significantly increases at alcohol concentrations of 0.6 to 0.8.

Conclusions:

• The interactions between chloride ions and solvents critically influence the structural and transport characteristics of choline chloride-based DES.
• Strategic addition of alcohols can tune DES properties for specific process industry applications.