Electrocatalytic conversion of carbon monoxide (CO) is being actively developed as a key component for tandem CO 2 electrolysis. Signi cant effort has been devoted to engineering CO reduction electrocatalysts for better multi-carbon product selectivity. However, less attention has been paid to other performance parameters, such as liquid product concentration and purity, which are crucial for commercializing CO electrolysis. Here, we present an "internally coupled puri cation" strategy to substantially improve the acetate concentration and purity in CO electrolysis. This improvement was achieved by incorporating both an anode electrocatalyst with high ethanol partial oxidation activity as well as an anion-exchange membrane with high ethanol permeability and good alkaline stability. We have successfully demonstrated stable 120-hour continuous operation of the CO electrolyzer at a xed current density of 200 mA cm − 2 and a full cell potential of < 2.3 V, producing an acetate product stream with a concentration of 1.9 M and a purity of 97.7%. By tuning the reaction conditions, we also showed that the concentration of the acetate production stream can be further increased to 7.6 M while maintaining a purity of > 99%. Additional mechanistic investigation revealed the roles of anode electrocatalysts and anion-exchange membranes in enhancing the acetate selectivity in CO electrolyzers. Finally, a technoeconomic analysis shows that a highly concentrated liquid product stream is essential to reduce the energy consumption associated with the product separation.

This review discusses potential microporous and mesoporous materials that can address the issue of sulfur reduction via adsorptive desulfurization (ADS) with a focus on liquid fuels. During the transition to cleaner energy sources in the face of climate change, liquid fossil fuels will likely continue to provide a significant share of the world's energy demand. Fossil fuels possess a substantial amount of deleterious sulfur compounds that reduce the efficiency of energy production, damage the environment, and harm human health. There has recently been a large push to address these challenges that sulfur presents. ADS is one of the most promising techniques to reduce the sulfur content of liquid fuels in a cost-effective manner. The three key materials that have attracted a great deal of attention for their application in ADS are metal-organic frameworks (MOFs), zeolites, and mesoporous silicas. These materials have emerged as potential candidates for ADS because of their high surface area, tunable structure, and advantageous porosity. Research interest has been generated around finding unique approaches to modify these materials that increase their selectivity, stability, adsorption capacity, and reusability. A deeper mechanistic understanding of the adsorption of various sulfur compounds on these novel materials has been pursued experimentally and with the aid of models. This review seeks to discuss the recent advances made surrounding the most promising ADS materials while providing an outlook on where advancements still need to be made.

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Electrocatalytic conversion of carbon monoxide (CO) is being actively developed as a key component for tandem CO2 electrolysis. Significant effort has been devoted to engineering CO reduction electrocatalysts for better multi-carbon product selectivity. However, less attention has been paid to other performance parameters, such as liquid product concentration and purity, which are crucial for commercializing CO electrolysis. Here, we present an “internally coupled purification” strategy to substantially improve the acetate concentration and purity in CO electrolysis. This improvement was achieved by incorporating both an anode electrocatalyst with high ethanol partial oxidation activity as well as an anion-exchange membrane with high ethanol permeability and good alkaline stability. We have successfully demonstrated stable 120-hour continuous operation of the CO electrolyzer at a fixed current density of 200 mA cm− 2 and a full cell potential of < 2.3 V, producing an acetate product stream with a concentration of 1.9 M and a purity of 97.7%. By tuning the reaction conditions, we also showed that the concentration of the acetate production stream can be further increased to 7.6 M while maintaining a purity of > 99%. Additional mechanistic investigation revealed the roles of anode electrocatalysts and anion-exchange membranes in enhancing the acetate selectivity in CO electrolyzers. Finally, a techno-economic analysis shows that a highly concentrated liquid product stream is essential to reduce the energy consumption associated with the product separation.