# Combining Electrochemical Reduction with Biosynthesis for Directed Conversion of CO2 into a Library of C3 Chemicals

## TL;DR

This study combines electrochemical and biological methods to convert CO2 into valuable C3 chemicals, offering a sustainable approach for carbon-neutral manufacturing.

## Contribution

A novel tandem system integrating electrochemical CO2 reduction with biosynthesis to produce a library of C3 chemicals.

## Key findings

- Electrochemical conversion of CO2 to acetic acid achieved a rate of 0.34 ± 0.01 g L−1 day−1.
- The system produced C3 chemicals like β-alanine (2.1 g/L), acrylic acid (752.4 mg/L), and L-lactic acid (672.9 mg/L).
- Conversion yields reached 0.54–0.72 tons of products per ton of CO2 with low energy consumption (51.88–80.7 GJ).

## Abstract

Electrochemical carbon dioxide (CO2) reduction presents significant opportunities for sustainable chemical manufacturing. However, conventional electrochemical CO2 reduction typically produces only C1 or C2 products, and the direct synthesis of C3 chemicals remains a major challenge. In this study, we developed a unique tandem system integrating microbial electroreduction with biosynthesis, demonstrating the feasibility of using CO2‐derived acetic acid as a carbon source for biosynthesis. In Module I, taking advantage of an established perfluorocarbon nanoemulsion strategy for enhanced H2 delivery, we achieved efficient electrocatalytic CO2‐to‐acetate conversion with an acetic acid production rate of 0.34 ± 0.01 g L−1 day−1. In Module II, the engineered was established by developing an ultrahigh mutation system to facilitate the screening of desirable microbes with high toxicity tolerance to acetic acid and different products. Various C3 chemicals were efficiently synthesized by this tandem system, including β‐alanine (2.1 g/L), acrylic acid (752.4 mg/L), and L‐lactic acid (672.9 mg/L), achieving a conversion yield of 0.54–0.72 tons of destined products per ton of CO2 with an energy consumption of only 51.88–80.7 GJ. This study introduced a novel approach for upcycling CO2 into a library of high‐value C3 chemicals, offering a new approach for achieving carbon neutrality.

In the H‐type electrolytic cell, carbon dioxide is reduced to acetic acid via electro‐microbial catalysis. The simply processed acetic acid is further converted through biological fermentation into high‐value‐added products, including acrylic acid, L‐lactic acid, and β‐alanine.