Large-scale screening of zeolite structures for CO2 membrane separations
Journal
Journal of the American Chemical Society
Journal Volume
135
Journal Issue
20
Pages
7545-7552
Date Issued
2013
Author(s)
Abstract
We have conducted large-scale screening of zeolite materials for CO 2/CH4 and CO2/N2 membrane separation applications using the free energy landscape of the guest molecules inside these porous materials. We show how advanced molecular simulations can be integrated with the design of a simple separation process to arrive at a metric to rank performance of over 87 000 different zeolite structures, including the known IZA zeolite structures. Our novel, efficient algorithm using graphics processing units can accurately characterize both the adsorption and diffusion properties of a given structure in just a few seconds and accordingly find a set of optimal structures for different desired purity of separated gases from a large database of porous materials in reasonable wall time. Our analysis reveals that the optimal structures for separations usually consist of channels with adsorption sites spread relatively uniformly across the entire channel such that they feature well-balanced CO2 adsorption and diffusion properties. Our screening also shows that the top structures in the predicted zeolite database outperform the best known zeolite by a factor of 4-7. Finally, we have identified a completely different optimal set of zeolite structures that are suitable for an inverse process, in which the CO2 is retained while CH4 or N2 is passed through a membrane. ? 2013 American Chemical Society.
Subjects
Diffusion properties
Free energy landscape
Graphics Processing Unit
Membrane separation
Molecular simulations
Optimal structures
Separation process
Zeolite materials
Adsorption
Algorithms
Computer graphics
Design
Porous materials
Program processors
Separation
Structural optimization
Carbon dioxide
carbon dioxide
zeolite
adsorption
article
binding site
chemical structure
crystal structure
diffusion coefficient
membrane permeability
molecular dynamics
Monte Carlo method
Carbon Dioxide
Diffusion
Methane
Molecular Dynamics Simulation
Molecular Structure
Nitrogen
Porosity
Surface Properties
Zeolites
SDGs
Type
journal article