Nefedov V., Bichay A., Polishchuk Yu. Analysis of electrolyser operation for producing hydrogen with soluble iron anode using mathematical model
- Details
- Parent Category: Geo-Technical Mechanics, 2025
- Category: Geo-Technical Mechanics, 2025, Issue 174
Geotech. meh. 2025, 174, 124-137
ANALYSIS OF ELECTROLYSER OPERATION FOR PRODUCING HYDROGEN WITH SOLUBLE IRON ANODE USING MATHEMATICAL MODEL
1Ukrainian State University of Science and Technologies
2M.S. Poliakov Institute of Geotechnical Mechanics of the National Academy of Sciences of Ukraine
UDC 544.6.018+544.652.076.324.4:661.961
Language: English
Abstract. The production of chemically pure hydrogen by electrochemical method has limitations due to the high cost of aqueous solutions electrolysis. To reduce the voltage on the electrolyzer, it is proposed to replace the anode process of oxygen evolution (standard potential in an acidic environment plus 1.23 V) with the dissolution of the anode from electronegative metals. Such metals can be aluminum and iron - the most common structural materials. Waste of these metals in the form of scrap or shavings is quite cheap and can be used in the form of packed electrode. The standard potential of iron is minus 0.44 V, and aluminum in an acidic medium is minus 2.30 V. When connecting an electrode (cathode) with a low overvoltage of hydrogen evolution to the anode, it becomes possible to obtain hydrogen with simultaneous generation of electricity. When using an iron anode, the voltage on the cell decreases to 0.5–0.6 V at a current density of about 0.1 A/cm2. The calculations and preliminary experiments showed that to reduce the polarization resistances of hydrogen evolution and iron dissolution, the composition of the anolyte and catholyte should be different. To reduce the polarization and ohmic resistances during electrolysis, a 1M HCl solution was chosen as the catholyte and a 5M NaCl solution - as the anolyte. Therefore, the anode and cathode chambers of the electrolyzer should be separated. Both porous diaphragms and anion exchange membranes can be used to separate the electrode chambers. For the diaphragms, the thickness, porosity and daily tortuosity coefficients are estimated. The properties of the diaphragms are determined not only by the energy costs of electrolysis (charge transfer processes), but also by the processes of substance transfer. For a well-grounded choice of diaphragm materials and the analysis of substance transfer processes in the electrolyzer, a mathematical model is proposed. Using this model, the values of diffusion and migration flows in the reactor are estimated. Moreover, the composition of the anolyte and catholyte are optimized, ensuring the flow of electrode processes with minimal energy costs; maintaining a given composition of solutions, and the possibility of their subsequent purification from electrolysis products.
Keywords: hydrogen, electrolysis, soluble iron anode, migration, diffusion, mathematical model.
REFERENCES
1. Kozin, L.F. and Volkov, S.V. (2002), Vodorodnaya ehnergetika i ehkologiya [Hydrogen energy and ecology], Naukova Dumka, Kyiv, Ukraine.
2. Nefedov, V.G., Matveev, V.V., Sykhyy, К.М., Bulat, A.F., Bluss B.O. and Mukhachev, A.P., M.S. Poliakov Institute of Geotechnical Mechanics of the National Academy of Sciences of Ukraine (2023), Sposib kompleksnogo oderzhannya vodnyu ta generatsii elektroenergii [Method for Integrated Hydrogen Production and Electricity Generation], State register of Patens of Ukraine, Kyiv, UA, Pat. No. 152585.
3. Nefedov, V.G., Matveev, V.V., Sykhyy, К.М., Bulat, A.F., Bluss B.O. and Mukhachev, A.P., M.S. Poliakov Institute of Geotechnical Mechanics of the National Academy of Sciences of Ukraine (2023), Sposib otrimannya vodnyu u vIdkritIy za masoperenosom elektrohImIchnIy sistemI zI znizhenimi energovitratami [Method for hydrogen producing in an open mass transfer electrochemical system with reduced energy consumption], State register of Patens of Ukraine, Kyiv, UA, Pat. No.154218.
4. Nefedov V., Matveev V., Sukhyy K., Polishchuk Yu., Bulat A., Bluss B. and Mukhachev, A. (2023), “Electrochemical production of hydrogen in reactors with reduced energy costs”, IOP Conf. Ser.: Earth Environ. Sci., vol. 1156, 012034. https://doi.org/10.1088/1755-1315/1156/1/012034
5. Karchiyappan, T. (2019), “A review on hydrogen energyproduction from electrochemical system: benefits and challenges”, Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, vol. 41, no. 7, pp. 902–909. https://doi.org/10.1080/15567036.2018.1520368
6.Suryanto, B.H.R., Wang, Y., Hocking, R.K., Adamson, W. and Zhao, C. (2019), “Overall electrochemical splitting of water at the heterogeneous interface of nickel and iron oxide”, Nature Communications, vol. 10, no. 44, 5599. https://doi.org/10.1038/s41467-019-13415-8
7. Ren, F., Xu, J. and Feng, L. (2024), “An effective bimetallic oxide catalyst of RuO2-Co3O4 for alkaline overall water splitting” NanoResearch, vol.17, pp. 3785–3793. https://doi.org/10.1007/s12274-023-6316-4
8. Subbaraman, R., Tripkovic, D., Chang, K.C. Strmcnik, D., Paulikas, A. P., Hirunsit, P., Chan, M., Greeley, J., Stamenkovic, V. and Markovic, N. M. (2012), “Trends in activity for the water electrolyser reactions on 3d M(Ni,Co,Fe,Mn) hydr(oxy)oxidecatalysts”, Nature Materials, vol. 11, pp. 550–557. https://doi.org/10.1038/nmat3313
9. Sakhnenko, M.D., Ved, M.V., Shtefan, V.V. and Volobyev, M.M. (2011), Teoretichni osnovi himii ridkisnih I rozsiyanih elementiv [Theoretical foundations of the chemistry of rare and scattered elements], HTU HPI, Kharkiv, Ukraine.
10. Yermolenko, I.Y., Ved, M.V. and Sakhnenko, M.D. (2014), Elektrohimichniy retsikling psevdosplaviv volframu [Electrochemical recycling of tungsten pseudoalloys], HTU HPI, Kharkiv, Ukraine.
11. Ved, M.V. and Sakhnenko, M.D. (2010), Katalitichni ta zahisni pokrittya splavami i skladnimi oksidami: elektrohimichniy sIntez, prognozuvannya, vlastivostey [Catalytic and protective coatings with alloys and complex oxides: electrochemical synthesis, prediction, properties], HTU HPI, Kharkiv, Ukraine.
12. Nefedov, V., Matveev, V., Polishchuk, Yu., Sukhyi, M. and Tulskyi, H. (2024), “Transfer processes in porous diaphragms and ion-exchange membranes for electrochemical reactor with reduced energy consumption”, IOP Conference Series: Earth and Environmental Science, vol.1348, 012058. https://doi.org/10.1080/1755-1315/1348/1/0112058
About the authors
Nefedov Volodymyr, Doctor of Technical Sciences (D.Sc.), Professor, Head of the Research Laboratory of Battery Systems and Energy in Ukrainian State University of Science and Technologies, Leading Researcher, M.S. Poliakov Institute of Geotechnical Mechanics of the National Academy of Sciences of Ukraine (IGTM of the NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. (Corresponding author), ORCID 0009-0001-5335-7738
Bichai Artem, Bachelor’s Degree, Ukrainian State University of Science and Technologies, Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. , ORCID 0009-0000-5883-1120
Polishchuk Yuliya, Candidate of Technical Sciences (Ph.D), Assistant professor, Director of the Scientific Center for Innovative Materials and Technologies Ukrainian State University of Science and Technologies, Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. , ORCID 0000-0003-1552-4117