Potential of organic carbonates production for efficient carbon dioxide capture, transport and storage: Reaction performance with sodium hydroxide-ethanol mixtures

Francisco M Baena-Moreno; Emmanouela Leventaki; Phuoc Hoang Ho; Abdul Raouf Tajik; Danica Brzic; Gaetano Sardina; Henrik Ström; Diana Bernin

doi:10.1016/j.heliyon.2023.e14140

Potential of organic carbonates production for efficient carbon dioxide capture, transport and storage: Reaction performance with sodium hydroxide-ethanol mixtures

Heliyon. 2023 Feb 27;9(3):e14140. doi: 10.1016/j.heliyon.2023.e14140. eCollection 2023 Mar.

Authors

Francisco M Baena-Moreno¹, Emmanouela Leventaki¹, Phuoc Hoang Ho¹, Abdul Raouf Tajik², Danica Brzic^{1

3}, Gaetano Sardina², Henrik Ström², Diana Bernin¹

Affiliations

¹ Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden.
² Department of Mechanics and Maritime Sciences, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.
³ University of Belgrade, Faculty of Technology and Metallurgy, Belgrade, Serbia.

Abstract

Carbon dioxide storage is one of the main long-term strategies for reducing carbon dioxide emissions in the atmosphere. A clear example is Norway's Longship project. If these projects should succeed, the transport of huge volumes of carbon dioxide from the emissions source to the injection points may become a complex challenge. In this work, we propose the production of sodium-based organic carbonates that could be transported to storage sites and be reconverted to CO₂. Solid carbonates can be transported in considerably lower volumes than gases or pressurized liquids. Sodium-based carbonates are insoluble in most of the organic solvents and will therefore precipitate in contrast to in aqueous solutions. Particularly, here we focus on sodium hydroxide-ethanol mixtures as solvents for precipitating sodium ethyl carbonate and sodium bicarbonate. Previous works on this approach used limited sodium hydroxide concentrations, which are insufficient to prove the effectiveness of the proposed process. In this paper, we studied higher sodium hydroxide concentrations in sodium hydroxide-ethanol mixtures than previously reported in the literature. To this end, we use the following strategy: (1) In-line monitoring of the formation of carbonates using an in-line FTIR; (2) In-line measurements of the weight increase, which correspond directly to the captured carbon dioxide and reveal the absorption capacity; (3) Characterization of the solids with X-ray diffraction and scanning electron microscope. Our FTIR results confirmed that both sodium ethyl carbonate and sodium bicarbonate were formed, which agrees with X-ray diffraction and scanning electron microscope. With this reactor design, the absorption capacities reached approximately 80-93% of the theoretical values (4.8-13.3 g/L respectively). We hypothesize that full conversion is hampered because the gas might take preferential paths due to gel formation during the experiments.

Keywords: Absorption capacity; Carbon capture; Chemical absorption; Organic carbonates; Transport and storage.