Rapid Exploration of Mixture Adsorption via Adiabatic Sampling
Caroline Desgranges1, Jerome Delhommelle2
1Department of Physics Applied Physics, University of Massachusetts, Lowell, Massachusetts 01854, United States.
Summary
Adiabatic simulations accelerate the prediction of gas storage and separation properties in porous materials. This new method significantly speeds up computational screening by overcoming simulation bottlenecks.
Area of Science:
- Computational materials science
- Physical chemistry
- Chemical engineering
Background:
- Accurate simulation of confined fluids is crucial for designing porous materials for gas storage and separations.
- Isothermal grand-canonical simulations face convergence issues near phase coexistence, limiting their efficiency.
Purpose of the Study:
- To develop and validate an adiabatic simulation method for mixtures to overcome limitations of isothermal simulations.
- To improve the computational efficiency of screening porous materials for gas applications.
Main Methods:
- Developed an adiabatic counterpart for mixture simulations.
- Derived acceptance rules for a grand-isochoric adiabatic Monte Carlo method.
- Compared adiabatic simulations with isothermal grand-canonical simulations for Ar-Kr mixtures in bulk and MCM-41.
Main Results:
- Adiabatic simulations enable large temperature variations, enhancing configuration space sampling.
- Achieved faster convergence, up to 2 orders of magnitude, compared to isothermal grand-canonical simulations.
- Demonstrated accuracy and efficiency for bulk and confined fluid mixtures.
Conclusions:
- Adiabatic simulations offer a more efficient approach for predicting phase diagrams and adsorption properties.
- This method significantly accelerates the computational screening of porous materials for gas storage and separation.
- The developed method addresses key challenges in simulating systems near phase coexistence.
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