Contaminants in an electrochemical cell converting CO₂ to formic acid can lead to the deactivation of cathode catalysts through several pathways, causing severe performance loss over time. Potential contaminants from flue gas emissions of principal fossil fuels include N₂, O₂, H₂O, CO, NO₂, SO₂, particulate matter and hydrocarbons. Contaminant effects on the CO₂ to formic acid electroreduction are scarcely covered in the literature. We describe in the present study these effects based on catalysts reported for the electroreduction of CO₂ to formic acid, focusing principally on copper, tin and lead in the two most popular configurations, 2 and 3 compartment cells. Water solubility, metal affinity through chemisorption, known chemical reactions and altered electrochemical activities are the main focus of this review. We herein highlight that O₂, SO₂ and particulate matter have especially detrimental effects. While O₂ can be efficiently removed from flue gas, additional treatment to remove SO₂ and particulate matter is required. Our conclusions should raise interest in experimentally validating the effect of such contaminants.

将CO ₂转化为甲酸的电化学电池中的污染物会导致阴极催化剂通过几种途径失活，从而导致长期性能严重下降。来自主要化石燃料的烟道气排放的潜在污染物包括N ₂，O ₂，H ₂ O，CO，NO ₂，SO ₂，颗粒物和碳氢化合物。文献中几乎没有涵盖对CO ₂进行甲酸电解还原的污染物影响。我们在本研究中基于报告的用于CO ₂电还原的催化剂描述了这些影响到甲酸，主要集中在两种最常见的配置（2和3隔室）中的铜，锡和铅上。水溶性，通过化学吸附的金属亲和力，已知的化学反应和改变的电化学活性是本文的重点。我们在此强调O ₂，SO ₂和颗粒物具有特别有害的作用。尽管可以从烟气中高效去除O _2，但仍需要进行额外处理以去除SO ₂和颗粒物。我们的结论应引起人们对通过实验验证此类污染物的作用感兴趣。