A numerical simulation of membrane-less water electrolyzer with flow-through-electrodes

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Abstract It is an ideal way to produce hydrogen by converting renewable energy into hydrogen energy using hydroelectricity. At conventional electrolysis, membrane occupies a large proportion in the cost of electrolytic device and brings high resistance, and the degradation of membrane is a short board that affects the life of electrolytic system. Membrane-less water electrolysis technology can effectively avoid the cost, life and resistance brought by membrane, which has great research significance. A two-dimensional numerical simulation model of membrane-less electrolysis with flow-through electrode was developed in this study firstly, taking the mass transport, momentum transport, electrochemical reaction, charge transport and their coupling relationship into comprehensive consideration. The ratio of overpotential in the total voltage caused by electrode activation, active area covered by bubbles and ohmic impedance was analyzed, and the influence of electrolyte flow rate and electrode gap thickness on the voltage drop of the whole system was emphatically studied. The results show that the active area covered by bubbles and the overpotential caused by ohmic impedance play a major role in the total voltage, both of which can be reduced by increasing electrolyte flow rate and decreasing electrode gap thickness. In order to ensure the electrolytic efficiency of the system and reduce the gas content in the gap, it is necessary to coordinate the electrolyte flow rate, current density and electrode gap thickness, so as to achieve the optimal performance.

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	SHEN Cen
	LIU Bolun
	MIN Luofu
	XU Wei
	WANG Yuxin

Keywords： alkaline water electrolysis membrane-less numerical simulation optimization design

Received 2022-03-30;

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SHEN Cen, LIU Bolun, MIN Luofu, XU Wei, WANG Yuxin.A numerical simulation of membrane-less water electrolyzer with flow-through-electrodes[J] Chemcial Industry and Engineering, 2024,V41(5): 61-72

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