Performance evaluation on CO2 fixation with chlorine gas production based on direct electrolysis of seawater

Abstract

CO2 fixation from seawater is an effective way to mitigate climate change and has gained widespread attention in recent years. However, the existing research mostly involves stoichiometric bases and bipolar membrane electrodialysis methods, and the performance of direct seawater electrolysis for CO2 fixation is presented with limited studies and rare research data. The performance evaluation on CO2 fixation based on the technology of direct seawater electrolysis is presented in this paper. Energy consumption, decalcification rate, and calcium carbonate production rate are employed as performance indexes to assess the feasibility of CO2 fixation through direct electrolysis of seawater. The simulation method is adopted in this paper, with validation based on data from experiment. As a result, the minimum energy consumption for per amount of calcium carbonate deposited ranges from 557.82 to 730.06 kJ/mol CaCO3 at the seawater flow rate range of 0.01–0.1 L/s, which has an advantage over other electrochemical CO2 capture method. Additionally, the decalcification rate and calcium carbonate production rate can reach a maximum of 100% and 0.36 mmol/s respectively. The conclusions presented in this paper can serve as a valuable guide for conducting large-scale evaluations or application analyses.