Extraction of CO₂from Seawater and Aqueous Bicarbonate Systems by Ion-Exchange Resin Processes

Abstract

Ion-exchange resins in dynamic seawater and model bicarbonate systems were studied to determine their feasibility and practicality for extracting large quantities of carbon dioxide from seawater for use as a carbon feedstock for fuel synthesis. The capacity and selectivity of both a strong acid cation-exchange resin and a strong base anion-exchange resin revealed that the cation-exchange resin total carbon dioxide recovery (0.32 mg/g of resin) was far superior to the anion-exchange capacity (0.07 mg/g of resin). In addition, the ease of regeneration of the cation-exchange resin was demonstrated using deionized water as a possible substitute for strong acids. The laboratory-scale data are used to estimate the full industrial-scale feasibility of a carbon-capture process by these approaches.