Connecting Material Characteristics with System Properties for Membrane-Based Direct Air Capture (m-DAC) Using Process Operability and Inverse Design Approaches

[Geoengineering News]

https://pubs.acs.org/doi/full/10.1021/acs.iecr.4c04553

Authors

Vitor Gama, Deepanjali Roy, Fernando V. Lima, Oishi Sanyal

10 April 2025

Abstract

This paper presents a process modeling approach for a two-staged membrane-based direct air capture (m-DAC) process, considering material characteristics, membrane separation, and system properties. m-DAC is a negative emissions technology for capturing dilute CO2 from air. Its continuous and modular nature could reduce economic challenges compared to sorption-based processes, which require costly regeneration. Facilitated transport membranes, with specialized CO2 carriers, offer higher performance than traditional sorption-diffusion membranes. Their key properties-the CO2 apparent diffusion coefficient (

𝐷CO2) and equilibrium constant (Keq)-determine membrane separation properties such as CO2 permeance and CO2/N2 selectivity. This work maps these inputs to feasible output spaces such as for CO2 recovery, purity, and capture cost. Additionally, inverse design is used to determine the required membrane properties for target system outcomes. Overall, this study provides a framework for membrane researchers to design cost-effective, scalable m-DAC solutions. 

Source: ACS Publications