HELVA project: converting CO2 into sustainable plastics using renewable energy and microbes

Coordinated by ICFO, the HELVA project aims to develop a novel technology based on hybrid tandem reactors that will produce bioplastics from CO2 waste. The project seeks to convert CO2 into acetate that will then be upgraded into bioplastic precursors (PHA) with the help of genetically modified bacteria.

Modern society and industry rely heavily on carbon-based molecules for the production of materials that are vital to multiple sectors, including construction, automotive, electronics, pharmaceuticals, textiles, food packaging or transportation fuels. These types of molecules are primarily obtained from fossil fuels, through energy-intensive thermochemical processes, which, as a result, cause the emission of greenhouse gases, especially carbon dioxide (CO2).

The extreme use of plastics exemplifies the world’s utter dependence on fossil fuels, since the whole cycle of production and consumption is based on petroleum. This dependence poses significant challenges for mitigating global warming and building sustainable circular economies.HELVA is a new European project led by ICFO that aims to turn CO2 into sustainable and biodegradable plastics.

The project seeks to develop a new conversion technology with a 2-step approach. Firstly, captured CO2 from the atmosphere and water will be transformed into acetate through a CO2 electroreduction (CO2R) process powered by renewable electricity (solar and wind).

Acetate is a type of salt formed by the combination of acetic acid (commonly known as vinegar) and a base and is widely used in several industrial sectors to produce, for example, paint, glue or plastics. Secondly, the resulting acetate will then be transformed by genetically modified microbes (bio-reactors) into polyhydroxyalkanoates (PHAs), a type of polymers which are the precursors for biodegradable plastics.

Selective CO2R faces significant limitations in generating complex substances like polymers, polyesters, fatty acids, and sugars. Furthermore, the electrosynthesis of acetate, as an intermediate feedstock, still faces issues regarding selectivity towards targeted products and the achieved current density.

In particular, the presence of non-desired by-products such as formate, methanol or ethanol could damage the microbial systems that are converting the acetate into the PHA.To achieve these objectives, HELVA will explore new materials and will design innovative catalysts that offer the required selectivity and productivity for acetate production.

The consortium also aims to develop genetically engineered microbes (Escherichia coli strains) capable of upgrading acetate into PHAs rates and purities ensuring a technological and economic viability of the process. The project team will finally develop the technology to integrate the CO2 electroreduction to acetate and the subsequent bio-driven upgrade to PHAs, addressing the limitations of both processes.

The HELVA consortium, coordinated by Prof. Pelayo García de Arquer from ICFO, is composed by an interdisciplinary team of researchers from the Lodz University of Technology (Poland) and the University of Sâo Paulo (Brazil).The project’s kick-off meeting was held online on 19th October. HELVA is a three-year project co-funded by the Agencia Estatal de Investigación (AEI, Spain), the National Science Centre (NCN, Poland) and the Sâo Paulo Research Fundation (FAPESP, Brazil) within the Joint Transnational Call 2022 of European funded network M-ERA.NET 3.