Boosting SO2-depolarized electrolysis with anodic HI for efficient and energy-saving hydrogen production
| Autor: | Zhi Ying, Jingyang Yang, Binlin Dou, Xiaoyuan Zheng, Guomin Cui |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Electrolysis
Materials science Hydrogen Renewable Energy Sustainability and the Environment Analytical chemistry Energy Engineering and Power Technology chemistry.chemical_element 02 engineering and technology Overpotential 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Redox 0104 chemical sciences law.invention Anode Reaction rate chemistry law Electrical and Electronic Engineering Physical and Theoretical Chemistry 0210 nano-technology Current density Hydrogen production |
| Zdroj: | Journal of Power Sources. 491:229589 |
| ISSN: | 0378-7753 |
| DOI: | 10.1016/j.jpowsour.2021.229589 |
| Popis: | The SO2-depolarized electrolysis (SDE) is a promising method for SO2 capture and hydrogen production. But the SDE is limited by the high overpotential and slow kinetics of anodic SO2 oxidation reaction (SOR). Herein, to boost SDE process, we add hydroiodic acid (HI) to the anolyte and form HI-assisted SO2-depolarized electrolysis (HASDE). The mechanism of HI assisted SOR is explored, the existence of HI reduces the onset potential and impedance, but increases current density and reaction rate of SOR. HI is supposed to change the single-step SOR into three-step reactions, without changing the overall anodic reaction. A HI concentration of less than or equal to 0.02 mol/L and an operating temperature of 50 °C or less are recommendable. The comparison of SDE and HASDE processes indicates that HASDE delivers a lower cell voltage than SDE during continuous constant-current electrolysis, and has negligible effect on cathodic H2 evolution, while it achieves 27.03–48.65% reduction in electric energy consumption compared with SDE. The present work provides an innovative strategy for improving SDE and energy-saving production of value-added chemicals like H2SO4 and H2. |
| Databáze: | OpenAIRE |
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