Electrochemical CO₂ conversion in eutectic Li-Ba and Li-Ca carbonate mixtures

Abstract

Here, the impact of electrolyte selection and electrolysis temperature on carbon morphology, energy consumption, and voltage efficiency in molten Li2CO3-BaCO3 and Li2CO3-CaCO3 electrolytes during 90 min 10 A constant current electrolysis are investigated. The scarcity of experimental investigations into these binary electrolytes, coupled with a lack of systematic investigation of temperature effects, necessitates further examination. The comprehensive analysis of the produced carbon reveals that both electrolyte composition and temperature influence carbon morphology. At lower temperatures the effect of electrolyte composition to the morphology is a more significant. The type and amount of metallic impurities mixed with the carbon vary depending on the electrolyte composition and electrolysis temperatures. The results from Li2CO3-CaCO3 electrolyte show more promising compared to results from Li2CO3-BaCO3 electrolyte in terms of product quality. Regarding electrolysis power and voltage efficiency, Li2CO3-CaCO3 proves equal or superior to other electrolytes, depending on temperature. Heat generation occurs in all the experiments, which emphasizes the importance maintaining a constant electrolysis temperature in industrial processes to manage heat generation effectively.