Renewable CO2 recycling plants (CO2RPs) for the production of chemicals play a certain role in the decarbonization of the economy. Significant progress has been made in recent years in the decarbonization of chemicals such as formate / formic acid (HCOO- / HCOOH) through electrochemical CO2 reduction (CO2ER). The traditional approach consists of the cathodic CO2ER coupled with the anodic oxygen evolution reaction (EOR). Current trends name alternative anodic processes, such as glycerine (GLY) electro-oxidation (EOG), as a powerful alternative to EOR, as it can noticeably lower the cell voltage. This newer alternative also leads to the formation of products in the anode with an economic value as O2, for example the fine chemical dihydroxyacetone (DHA). So far, other factors than just energy savings in the ER cell have been neglected. Other factors such as anodic market size, downstream separation energy needs, etc. need to be considered in the overall picture of decarbonization. In the present study, we analyze the ecological and economic advantages of the integrated production of HCOO and DHA by a renewable CO2RP when the traditional EOR is replaced by the EOG alternative. Life cycle thinking was used to aid decision making. HCOO and DHA fossil routes as well as the traditional decarbonization EOR scheme (which decarbonized the amount of HCOO) were used for benchmarking. The integrated production in the proposed CO2RP is severely restricted by the small market size of DHA compared to HCOO and also by the high energy requirements in the DHA purification step. Anodic DHA concentration above 1.5% by weight. is mandatory for short and medium term developments in order to achieve a positive decarbonisation scenario when the integrated production of DHA and HCOO is compared with the traditional way. A noticeable reduction in the DHA market price would be possible with proper anode developments. In addition, we evaluate the influence of the market forecast for renewable electricity on the economic figures of DHA and HCOO- produced by the co-electrolysis technology.


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