2025 AIChE Annual Meeting

(566h) Design and Characterization of Gas Separation Polymer Membranes Using Molecular Simulation

Authors

Entao Yang, Air Liquide
Luis Pinto, Air Liquide
Yi Ren, Air Liquide
Zachary Wilson, Air Liquide
Junyi Liu, Air Liquide
Pluton Pullumbi, Air Liquide
Robert Riggleman, University of Pennsylvania
Polymer membranes can serve as a low-carbon alternative to conventional thermal separations in processes like natural gas upgrading or CO2 removal from other gas streams. Effectively exploring the design space of polymers to find candidate materials that provide adequate gas permeance and selectivity for a given separation can be challenging, and aided by tools such as machine learning models and molecular simulation prior to experimental synthesis. In this work, we show how molecular dynamics (MD) and Monte Carlo (MC) simulations with atomistic detail may be used to characterize the gas permeance behavior of both existing and novel polymers, in not only the pure gas case but also under operationally-relevant mixed-gas conditions. We produce sorption isotherms for both cases using hybrid MD/MC simulation and calculate diffusion coefficients using long-time molecular dynamics. to determine gas permeance according to a solution-diffusion model. Understanding the mixed-gas performance of membranes is crucial to accurately predict their effectiveness, as the coexistence of strongly interacting gases like CO2 can play a significant role in the transport of other components in a gas mixture. In conjunction with experimental study, molecular simulation can be used to accelerate materials development for the next generation of membrane materials needed to tackle separations challenges on a global level.