Eliminating active CO2 concentration in Carbon Capture and Storage (CCUS): Molten carbonate decarbonization through an insulation/diffusion membrane
Gad Licht, Ethan Peltier, Simon Gee, Stuart Licht
Abstract
Present industrial decarbonization technologies require an active CO 2 -concentration system, often based on lime reaction or amine binding reactions, which is energy intensive and carries a high CO 2 -footprint. Here instead, an effective process without active CO 2 concentration is demonstrated in a new process-termed IC2CNT (Insulation-diffusion facilitated CO 2 to Carbon Nanomaterial Technology) decarbonization process. Molten carbonates such as Li 2 CO 3 (mp 723 °C) are highly insoluble to industrial feed gas principal components (N 2 , O 2 , and H 2 O). However, CO 2 can readily dissolve and react in molten carbonates. We have recently characterized high CO 2 diffusion rates through porous aluminosilicate and calcium-magnesium silicate thermal insulations. Here, the CO 2 in ambient feed gas passes through these membranes into molten Li 2 CO 3 . The membrane also concurrently insulates the feed gas from the hot molten carbonate chamber, obviating the need to heat the (non-CO 2 ) majority of the feed gas to high temperature. In this insulation facilitated decarbonization process CO 2 is split by electrolysis in the molten carbonate producing sequestered, high-purity carbon nanomaterials (such as CNTs) and O 2 .