Highly Efficient CO₂ Utilization via Molten Salt CO₂ Capture and Electrochemical Transformation Technology

Authors

Bo-wen DENG, School of Resources and Environmental Science, Wuhan University, Wuhan 430072, Hubei, China;
Hua-yi YIN, School of Resources and Environmental Science, Wuhan University, Wuhan 430072, Hubei, China;
Di-hua WANG, School of Resources and Environmental Science, Wuhan University, Wuhan 430072, Hubei, China;Follow

Corresponding Author

Di-hua WANG(wangdh@whu.edu.cn)

Abstract

The molten electrolytes exhibit high CO₂ absorption capacities, wide electrochemical windows and excellent reaction kinetics, which are promising electrolyte candidates for efficient capture and electrochemical conversion of high-flux CO₂ driven by renewable and clean electricity sources. This short review introduces the recent advancements of CO₂ electroreduction achieved by the authors using molten salt CO₂ capture and electrochemical transformation (MSCC-ET) technology, involving CO₂ absorption kinetics, cathodic kinetics, controllable synthesis of carbon products with unique nanostructures, development of inert oxygen evolution anodes and CO₂ conversion efficiency as well as energy efficiency. The challenges and prospects are also discussed based on the critical review.

Graphical Abstract

Keywords

molten electrolytes, CO2 reduction, cathodic kinetics, carbon materials, inert anode, MSCC-ET

DOI Link

https://doi.org/10.13208/j.electrochem.200653

Publication Date

2020-10-28

Online Available Date

2020-10-28

Revised Date

2020-09-16

Received Date

2020-07-17

Recommended Citation

Bo-wen DENG, Hua-yi YIN, Di-hua WANG. Highly Efficient CO₂ Utilization via Molten Salt CO₂ Capture and Electrochemical Transformation Technology[J]. Journal of Electrochemistry, 2020 , 26(5): 628-638.
DOI: 10.13208/j.electrochem.200653
Available at: https://jelectrochem.xmu.edu.cn/journal/vol26/iss5/4

References

[1] Yang Y, Ajmal S, Zheng X Y, et al. Efficient nanomaterials for harvesting clean fuels from electrochemical and photoelectrochemical CO₂ reduction[J]. Sustainable Energy & Fuels, 2018,2(3):510-537.

[2] De Luna P, Hahn C, Higgins D, et al. What would it take for renewably powered electrosynjournal to displace petrochemical processes?[J]. Science, 2019, 364(6438): eaav3506.
doi: 10.1126/science.aav3506 URL pmid: 31023896

[3] Burdyny T, Smith W A. CO₂ reduction on gas-diffusion electrodes and why catalytic performance must be assessed at commercially-relevant conditions[J]. Energy & Environmental Science, 2019,12(5):1442-1453.

[4] Jiang R, Gao M X, Mao X H, et al. Advancements and potentials of molten salt CO₂ capture and electrochemical transformation (MSCC-ET) process[J]. Current Opinion in Electrochemistry, 2019,17:38-46.
doi: 10.1016/j.coelec.2019.04.011 URL

[5] Bartlett H E, Johnson K E. Electrochemical studies in molten Li₂CO₃-Na₂CO₃[J]. Journal of The Electrochemical Society, 1967,114(5):457-461.
doi: 10.1149/1.2426627 URL

[6] Yin H Y, Mao X H, Tang D Y, et al. Capture and electrochemical conversion of CO₂ to value-added carbon and oxygen by molten salt electrolysis[J]. Energy & Environmental Science, 2013,6(5):1538-1545.

[7] Ijije H V, Sun C, Chen G Z. Indirect electrochemical reduction of carbon dioxide to carbon nanopowders in molten alkali carbonates: Process variables and product properties[J]. Carbon, 2014,73:163-174.
doi: 10.1016/j.carbon.2014.02.052 URL

[8] Ren J, Li F F, Lau J, et al. One-pot synjournal of carbon nanofibers from CO₂[J]. Nano Letters, 2015,15(9):6142-6148.
doi: 10.1021/acs.nanolett.5b02427 URL pmid: 26237131

[9] Hu L W, Song Y, Ge J B, et al. Capture and electrochemical conversion of CO₂ to ultrathin graphite sheets in CaCl₂-based melts[J]. Journal of Materials Chemistry A, 2015,3(42):21211-21218.
doi: 10.1039/C5TA05127D URL

[10] Wang D H(汪的华), Chen Z(陈政). Innovation in molten salt electrochemistry[J]. Journal of the Electrochemistry (电化学), 2005,11(2):119-124.

[11] Xiao W(肖巍), Zhu H(朱华), Yin H Y(尹华意), et al. Novel molten-salt electrolysis processes towards low-carbon metallurgy[J]. Journal of the Electrochemistry (电化学), 2012,18(3):193-200.

[12] Yin H Y, Wang D H. Electrochemical valorization of carbon dioxide in molten salts[M] //Li L, Wong-Ng W, Huang K, et al. Materials and processes for CO₂ capture, conversion, and sequestration. New York: John Wiley & Sons, Inc., 2018: 267-295.

[13] Deng B W(邓博文), Song Y Q(宋宇桥), Mao X H(毛旭辉), et al. Capture and electrochemical conversion of CO₂ in high-temperature molten salts[J]. Journal of Wuhan University(Natural Science Edition) (武汉大学学报(理学版)), 2016,62(1):1-8.

[14] Deng B W, Tang J J, Mao X H, et al. Kinetic and thermodynamic characterization of enhanced carbon dioxide absorption process with lithium oxide-containing ternary molten carbonate[J]. Environmental Science & Technology, 2016,50(19):10588-10595.
doi: 10.1021/acs.est.6b02955 URL pmid: 27602783

[15] Deng B W, Chen Z G, Gao M X, et al. Molten salt CO₂ capture and electro-transformation (MSCC-ET) into capacitive carbon at medium temperature: effect of the electrolyte composition[J]. Faraday Discussions, 2016,190:241-258.
doi: 10.1039/c5fd00234f URL pmid: 27193751

[16] Wakamatsu T, Uchiyama T, Natsui S, et al. Solubility of gaseous carbon dioxide in molten LiCl-Li₂O[J]. Fluid Phase Equilibria, 2015,385:48-53.
doi: 10.1016/j.fluid.2014.10.046 URL

[17] Hu L W, Song Y, Ge J B, et al. Electrochemical deposition of carbon nanotubes from CO₂ in CaCl₂-NaCl-based melts[J]. Journal of Materials Chemistry A, 2017,5(13):6219-6225.
doi: 10.1039/C7TA00258K URL

[18] Tang D Y, Yin H Y, Mao X H, et al. Effects of applied voltage and temperature on the electrochemical production of carbon powders from CO₂ in molten salt with an inert anode[J]. Electrochimica Acta, 2013,114:567-573.
doi: 10.1016/j.electacta.2013.10.109 URL

[19] Gao M X, Deng B W, Chen Z G, et al. Cathodic reaction kinetics for CO₂ capture and utilization in molten carbonates at mild temperatures[J]. Electrochemistry Communications, 2018,88:79-82.
doi: 10.1016/j.elecom.2018.02.003 URL

[20] Gao M X, Deng B W, Chen Z G, et al. Enhanced kinetics of CO₂ electro-reduction on a hollow gas bubbling electrode in molten ternary carbonates[J]. Electrochemistry Communications, 2019,100:81-84.
doi: 10.1016/j.elecom.2019.01.026 URL

[21] Deng B W, Gao M X, Yu R, et al. Critical operating conditions for enhanced energy-efficient molten salt CO₂ capture and electrolytic utilization as durable looping applications[J]. Applied Energy, 2019,255:113862.

[22] Gao M X, Chen Z G, Deng B W, et al. (Invited) Electrochemical deposition of carbon materials in molten salts[J]. ECS Transactions, 2017,80(10):791-799.

[23] Gu Y X(谷雨星), Yang J(杨娟), Wang D H(汪的华). Electrochemical features of carbon prepared by molten salt electro-reduction of CO₂[J]. Acta Physico-Chimica Sinica (物理化学学报), 2018,35(2):208-214.

[24] Tang J J, Deng B W, Xu F, et al. The lithium storage performance of electrolytic-carbon from CO₂[J]. Journal of Power Sources, 2017,341:419-426.

[25] Tang D Y, Dou Y P, Yin H Y, et al. The capacitive performances of carbon obtained from the electrolysis of CO₂ in molten carbonates: effects of electrolysis voltage and temperature[J]. Journal of Energy Chemistry, 2019. DOI: 10.1016/j.jechem.2019.11.006.

[26] Mao X H, Yan Z P, Sheng T, et al. Characterization and adsorption properties of the electrolytic carbon derived from CO₂ conversion in molten salts[J]. Carbon, 2017,111:162-172.

[27] Jiang D, Yang J, Wang D H. Green carbon material for organic contaminants adsorption[J]. Langmuir, 2020,36(12):3141-3148.
doi: 10.1021/acs.langmuir.9b03811 URL pmid: 32146816

[28] Chen Z G, Gu Y X, Du K F, et al. Enhanced electrocatalysis performance of amorphous electrolytic carbon from CO₂ for oxygen reduction by surface modification in molten salt[J]. Electrochimica Acta, 2017,253:248-256

[29] Ge J B, Wang S, Zhang F, et al. Electrochemical preparation of carbon films with a MO₂C interlayer in LiCl-NaCl-Na₂CO₃ melts[J]. Applied Surface Science, 2015,347:401-405.

[30] Chen Z G, Deng B W, Du K F, et al. Flue-gas-derived sulfur-doped carbon with enhanced capacitance[J]. Advanced Sustainable Systems, 2017,1(6):1700047.

[31] Chen Z G, Gu Y X, Hu L Y, et al. Synjournal of nanostructured graphite: via molten salt reduction of CO₂ and SO₂ at a relatively low temperature[J]. Journal of Materials Chemistry A, 2017,5(39):20603-20607.

[32] Deng B W, Tang J J, Gao M X, et al. Electrolytic synjournal of carbon from the captured CO₂ in molten LiCl-KCl-CaCO₃: critical roles of electrode potential and temperature for hollow structure and lithium storage performance[J]. Electrochimica Acta, 2018,259:975-985.

[33] Deng B W, Mao X H, Xiao W, et al. Microbubble effect-assisted electrolytic synjournal of hollow carbon spheres from CO₂[J]. Journal of Materials Chemistry A, 2017,5(25):12822-12827.

[34] Hu L W, Song Y, Jiao S Q, et al. Direct conversion of greenhouse gas CO₂ into graphene via molten salts electrolysis[J]. ChemSusChem, 2016,9(6):588-594.
URL pmid: 26871684

[35] Wu H G, Liu Y, Ji D Q, et al. Renewable and high efficient syngas production from carbon dioxide and water through solar energy assisted electrolysis in eutectic molten salts[J]. Journal of Power Sources, 2017,362:92-104.

[36] Liu Y, Yuan D D, Ji D Q, et al. Syngas production: diverse H₂/CO range by regulating carbonates electrolyte composition from CO₂/H₂O: via co-electrolysis in eutectic molten salts[J]. RSC Advances, 2017,7(83):52414-52422.

[37] Du K F, Zheng K Y, Chen Z G, et al. Unusual temperature effect on the stability of nickel anodes in molten carbonates[J]. Electrochimica Acta, 2017,245:402-408.

[38] Zheng K Y, Du K F, Cheng X H, et al. Nickel-iron-copper alloy as inert anode for ternary molten carbonate electrolysis at 650^oC[J]. Journal of The Electrochemical Society, 2018,165(11):E572-E577.

[39] Zheng K Y, Cheng X H, Dou Y P, et al. Electrolytic production of nickel-cobalt magnetic alloys from solid oxides in molten carbonates[J]. Journal of The Electrochemical Society, 2017,164(13):E422-E427.

[40] Cheng X H, Yin H Y, Wang D H. Rearrangement of oxide scale on Ni-11Fe-10Cu alloy under anodic polarization in molten Na₂CO₃-K₂CO₃[J]. Corrosion Science, 2018,141:168-174.

[41] Wang P L, Du K F, Dou Y P, et al. Corrosion behaviour and mechanism of nickel anode in SO₄^2- containing molten Li₂CO₃-Na₂CO₃-K₂CO₃[J]. Corrosion Science, 2020,166:108450.

[42] Du K F, Yu R, Gao M X, et al. Durability of platinum coating anode in molten carbonate electrolysis cell[J]. Corrosion Science, 2019,153:12-18.

[43] Moomaw W, Burgherr P, Heath G, et al. Annex II: Meth-odology[M]//Edenhofer O, Pichs-Madruga R, Sokona Y, et al. IPCC special report on renewable energy sources and climate change mitigation. Cambridge: Cambridge University Press, 2011: 10-11.