(472b) Screening of Metal Organic Framework Based Membranes for Carbon Dioxide Separations Using Atomically Detailed Simulations

Membranes offer a promising approach for energy-efficient separation of gas mixtures. Although large numbers of nanoporous materials exist that are potentially suitable for use as gas separation membranes, the experimental challenge of fabricating defect-free thin films makes screening of these materials a laborious process. Atomically detailed simulations are a useful complement to experimental studies for this problem in order to screen numerous materials prior to fabrication of membranes. These simulations guide experiments to focus on more useful membrane materials by predicting the material properties needed to characterize membrane performance beforehand.

The aim of our work is to use atomically detailed simulations in order to describe macroscopic transport of various gas molecules both as single components and as mixtures in a new group of material, namely metal organic frameworks (MOFs). By using a multi-scale approach in our modeling, we are able to link atomically-detailed descriptions of each material with predictions of membrane performance under practical operating conditions. We focused initially on two well known MOF structures, MOF-5 and CuBTC, to examine the separation capacity of these two materials as membranes. Our results gave the first insight into whether pursuing the fabrication of membranes for gas separations from MOFs would be a useful activity. We will show how insight from these initial calculations can be used to choose candidate materials from the very large number of MOFs that are known for specific membrane applications.