Performance evaluation of biogenic CO2-based renewable chemicals: A holistic life cycle assessment and multi-criteria approach

Abstract

The decarbonization of the chemical sector is challenging due to its dependence on fossil-based feedstocks and energy-intensive processes. The capture and utilization of biogenic CO₂ offer a promising route to carbon circularity and climate change mitigation through the production of renewable, high-value biochemicals. This study presents an integrated environmental and economic evaluation of emerging bioprocesses that convert biogenic CO₂ into value-added chemicals using gas and liquid fermentation pathways. Life cycle assessment and life cycle costing are employed to evaluate the environmental and economic performance. A hybrid multi-criteria decision-making framework, combining the Analytic Hierarchy Process and the Technique for Order Preference by Similarity to Ideal Solution, ranks the alternatives based on their environmental, economic, and technological attributes. The results indicate that the pathways can achieve net-negative greenhouse gas emissions, ranging from −2.43 to −0.38 kg CO_2eq per kg of biochemical, primarily due to the permanent sequestration of biogenic carbon within the final products. Production costs, assessed at the pilot scale, vary between €15.17 and €23.21 per kg, highlighting the influence of scale and process configuration. The findings provide robust evidence of the environmental benefits and potential economic trade-offs associated with biogenic CO₂ utilization in the chemical industry, supporting its integration as a viable decarbonization pathway and facilitating the scale up of carbon capture and utilization technologies in alignment with low-carbon chemical manufacturing and energy transition goals.