# Evaluation of Process Parameters for Integrated CO2 Electrolysis to Produce Ethylene

## TL;DR

This study examines how process parameters affect ethylene production in CO2 electrolysis, finding that higher catholyte flow rates improve efficiency.

## Contribution

The study identifies catholyte flow rate as a critical parameter for improving ethylene selectivity in integrated CO2 electrolysis.

## Key findings

- Higher catholyte flow rates increase ethylene Faraday efficiency by reducing mass transport limitations.
- Increasing pressure or temperature does not significantly improve ethylene selectivity.
- Mass transport limitations are more impactful than CO2 availability in determining efficiency.

## Abstract

Electrochemical CO2 reduction provides a promising strategy for reducing greenhouse gas emissions by converting CO2 into chemicals such as ethylene. Integrated CO2 electrolysis, using CO2‐enriched absorbent solutions, is a cost‐effective alternative to gas‐fed systems due to reduced process complexity. However, for industrial applications, the process parameters need to be optimized to enhance selectivity and efficiency. Despite advances in catalyst and cell design, the impact of operational factors like catholyte flow rate, pressure, and temperature on C2+ product selectivity remains largely unexplored. This study systematically investigates the effects of catholyte flow rate, overpressure, and temperature on ethylene selectivity in integrated CO2 electrolysis with a potassium carbonate absorbent. Our results show that increasing the catholyte flow rate enhances the Faraday efficiency for ethylene by mitigating mass transport limitations between the flow field and the catalyst layer, whereas increasing pressure or temperature does not yield similar improvements. This insight shifts the focus from stoichiometric availability of physically dissolved CO2 to mass transport limitations, suggesting that further advances in cell design could unlock higher conversion efficiencies. Our study provides a foundation for scaling up integrated CO2 electrolysis by highlighting the importance of improving mass transport, a key step toward industrial implementation of sustainable CO2 conversion technologies.

This work systematically explores how flow rate, pressure, and temperature influence ethylene selectivity in integrated CO2 electrolysis with a potassium carbonate absorbent. Findings reveal that higher catholyte flow rates improves Faraday efficiency for ethylene by overcoming mass transport barriers, while increased pressure or temperature does not. This highlights mass transport as a key factor, informing strategies for scaling up integrated CO2 electrolysis and advancing sustainable CO2 utilization.© 2026 WILEY‐VCH GmbH