Separation and concentration of CO₂ from air using a humidity-driven molten-carbonate membrane.

ABSTRACT: Separation processes are substantially more difficult when the species to be separated is highly dilute. To perform any dilute separation, thermodynamic and kinetic limitations must be overcome. Here we report a molten-carbonate membrane that can 'pump' CO₂ from a 400 ppm input stream (representative of air) to an output stream with a higher concentration of CO₂, by exploiting ambient energy in the form of a humidity difference. The substantial H₂O concentration difference across the membrane drives CO₂ permeation 'uphill' against its own concentration difference, analogous to active transport in biological membranes. The introduction of this H₂O concentration difference also results in a kinetic enhancement that boosts the CO₂

SUBMITTER: Metcalfe IS 

PROVIDER: S-EPMC11420091 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature