Converting CO2 into high-value-added organic acids via microbial electrosynthesis (MES) is one of the critical pathways to achieve the carbon neutrality goal.To address the technical bottlenecks of traditional organic acid separation technologies,including high energy consumption,insufficient selectivity and poor compatibility with biosynthetic systems,this study investigates the organic acid separation performance of ion-driven capacitive deionization (CDI) technology.By constructing a quaternary organic acid mixed simulation system and integrating electrochemical tests,mass transfer simulation and material characterization,the regulation mechanisms of carbon chain length,operating parameters and electrode materials are clarified.The results show that the total ion removal efficiency reaches 58.2% when α-TiO2@g-C3N4 is used as the cathode,with the optimal process parameters being a flow rate of 0.005 m/s and a voltage of 1.5-1.8 V.This study provides data support for the industrial application of CDI technology and is of great significance for promoting the full-chain industrialization of MES.
为了深入解析α-TiO2@g-C3N4电极材料对四元有机酸混合体系(甲酸、乙酸、丙酸、丁酸)的电吸附分离机理,使用Finite Element Analysis(FEA)进行模拟分析计算,构建了高保真的二维多物理场耦合模型,结合公式(1)、(2),通过过程分布参数的计算,探究CDI电极增强四元有机酸分离性质与机理。
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