Work

Brines as autocatalytic reaction/separation platform to convert CO2 to organic carbonates: Integrating CO2 emissions and brines management

Year: 2025

Type: article

Abstract: Several environmental issues are demanding urgent solutions to improve the sustainability of the future. In this work, two relevant and independent environmental issues, such as brines and CO 2 management are investigated together, trying to find technological solutions that can incorporate synergies in the search for carbon–water cycle optimization, decarbonization, waste management, and resource utilization. Inorganic salts presented in brines were shown to be effective catalysts to convert CO 2 to cyclic carbonates by cycloaddition to epoxides, whereas water is an ideal solvent to separate hydrophobic cyclic carbonates from inorganic salt catalysts with hydrophilic character. Although the hydrophobic character of epoxide reactant can impose some limitations in the reaction step, byproduct recycling can be an effective way to enable competitive catalytic activity and, thus, promote the widespread use of this innovative process. In addition, the purification of the cyclic carbonate is coupled with the isolation of a treated water stream, which is another product obtained. Although less desirable, the third product corresponds to the diol derived from the reaction of water with each epoxide, envisioning a coproduction scheme providing three valuable products (cyclic carbonate, diol, and water) from two wastes (brines and CO 2 ) and one epoxide. Preliminary kinetic study and calculated energy consumption (1.87 kWh/kg of products) show competitiveness when evaluating individual water separation from brines and cyclic carbonate and diol productions, demonstrating the viability of this new process. The work also opens a new horizon for sustainability since global warming potential (0.148 kgCO 2 /kg) and water depletion (−0.144 m 3 water/kg of products) improve reference individual technologies.

Source: Chemical Engineering Journal

DOI: 10.1016/j.cej.2025.162719

Authors: Alejandro Belinchón, Elisa Hernández, Álvaro Julián, Pablo Navarro, José Palomar

Institution: Universidad Autónoma de Madrid

Language: English

Topic: Carbon dioxide utilization in catalysis

Subfield: Process Chemistry and Technology

Field: Chemical Engineering

Domain: Physical Sciences

SDGs: Responsible consumption and production, Climate action, Clean water and sanitation

Open Access status: hybrid

Estimated APC paid: $4,830