Export file:


  • RIS(for EndNote,Reference Manager,ProCite)
  • BibTex
  • Text


  • Citation Only
  • Citation and Abstract

Experimental evaluation of chemical systems for CO2 capture by CaO in eutectic CaF2-CaCl2

1 Faculty of Science and Technology, Norwegian University of Life Sciences (NMBU), N-1432 Ås, Norway
2 AGH University of Science and Technology, Faculty of Non-Ferrous Metals, Kraków, Poland

Special Issues: Industrial symbiosis: waste management practices within industries for sustainable environment

CO2 capture by CaO in molten salts is a variant of calcium looping in which the active substances (CaO/CaCO3) are dissolved or in a slurry with inorganic molten salts. One of the main advantages is the nonexistence of degradation in the reactivity between the active material and CO2. Previous research has revealed good absorption and desorption characteristics with CaO contents up to 20 wt% in eutectic CaF2-CaCl2. The hypothesis is that the formed CaCO3 continuously dissolves in the melt, leaving highly reactive CaO readily available for the incoming CO2. In the present study, the CaO content is increased to 40 wt%, and the absorption characteristics is investigated with focus on the sorption capacity and CO2 removal rate. The chemical system is also evaluated experimentally with regards to viscosity and solubility of the formed CaCO3 during CO2 absorption, with the aim of determining chemical upscaling limitations. The results show that the practical CaO content limit is 30 wt%, in which a sorption capacity of 20 g CO2/100 g sorbent is observed, without any deterioration of the reaction kinetics. For 40 wt% CaO, the sorption capacity is higher, but on the expense of the CO2 removal rate and CaO conversion. This is attributed to a significant increase in viscosity and the solubility limit of CaCO3 being exceeded.
  Article Metrics


1. Chu S (2009) Carbon capture and sequestration. Science 325: 1599.    

2. Pires JCM, Martins FG, Alvim-Ferraz MCM, et al. (2011) Recent developments on carbon capture and storage: An overview. Chem Eng Res Des 89: 1446-1460.    

3. MacDowell N, Florin N, Buchard A, et al. (2010) An overview of CO2 capture technologies. Energy Environ Sci 3: 1645-1669.    

4. Dean CC, Blamey J, Florin NH, et al. (2011) The calcium looping cycle for CO2 capture from power generation, cement manufacture and hydrogen production. Chem Eng Res Des 89: 836-855.    

5. Blamey J, Anthony EJ, Wang J, et al. (2010) The calcium looping cycle for large-scale CO2 capture. Prog Energy Combust Sci 36: 260-279.    

6. Grasa GS, Abanades JC (2006) CO2 Capture Capacity of CaO in Long Series of Carbonation/Calcination Cycles. Ind Eng Chem Res 45: 8846-8851.    

7. Manovic V, Anthony EJ (2010) Lime-based sorbents for high-temperature CO2 capture-A review of sorbent modification methods. Int J Environ Res Public Health 7: 3129-3140.    

8. Li Z, Liu Y, Cai N (2013) Understanding the effect of inert support on the reactivity stabilization for synthetic calcium based sorbents. Chem Eng Sci 89: 235-243.    

9. Kazi SS, Aranda A, Meyer J, et al. (2014) High performance CaO-based sorbents for pre-and post-combustion CO2 capture at high temperature. Energy Procedia 63: 2207-2215.    

10. Al-Jeboori MJ, Nguyen M, Dean C, et al. (2013) Improvement of limestone-based CO2 sorbents for Ca looping by HBr and other mineral acids. Ind Eng Chem Res 52: 1426-1433.    

11. Liu W, Yin J, Qin C, et al. (2012) Synthesis of CaO-based sorbents for CO2 capture by a spray-drying technique. Environ Sci Technol 46: 11267-11272.    

12. Stendardo S, Andersen LK, Herce C (2013) Self-activation and effect of regeneration conditions in CO2-carbonate looping with CaO-Ca12Al14O33 sorbent. Chem Eng J 220: 383-394.    

13. Olsen E, Tomkute V (2013) Carbon capture in molten salts. Energy Sci Eng 1: 144-150.    

14. Bhatia SK, Perlmutter DD (1983) Effect of the product layer on the kinetics of the CO2‐lime reaction. AIChE J 29: 79-86.    

15. Tomkute V, Solheim A, Olsen E (2013) Investigation of high-temperature CO2 capture by CaO in CaCl2 molten salt. Energy Fuels 27: 5373-5379.    

16. Tomkute V, Solheim A, Olsen E (2014) CO2 capture by CaO in molten CaF2-CaCl2: Optimization of the process and cyclability of CO2 capture. Energy Fuels 28: 5345-5353.    

17. Tomkute V, Solheim A, Sakirzanovas S, et al. (2016) Reactivity of CaO with CO2 in molten CaF2-NaF: formation and decomposition of carbonates. Energy Sci Eng 4: 205-216.    

18. Nygård HS, Tomkute V, Olsen E (2017) Kinetics of CO2 Absorption by Calcium Looping in Molten Halide Salts. Energy Procedia 114: 250-258.    

19. Freidina EB, Fray DJ (351) Phase diagram of the system CaCl2-CaCO3. Thermochim acta 351: 107-108.

20. Lide DR (2004) CRC Handbook of Chemistry and Physics. 85th Edition, Taylor & Francis.

© 2019 the Author(s), licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution Licese (http://creativecommons.org/licenses/by/4.0)

Download full text in PDF

Export Citation

Article outline

Show full outline
Copyright © AIMS Press All Rights Reserved