Decarbonizing Acetic Acid Production with CO2-Based Feedstocks: A Multiregional Prospective Life Cycle Assessment

Abstract

Acetic acid plays a central role in the chemical industry, where its large production volumes are linked to notable greenhouse gas emissions. To explore pathways toward more sustainable production, this study combines a detailed process simulation of the Cativa process with cradle-to-gate life cycle assessment and prospective life cycle inventories derived from the REMIND integrated assessment model scenario SSP2-PkBudg1000. Building on the ecoinvent v3.12 database and the premise framework, we evaluate fossil-based against CO2-derived feedstocks for acetic acid production across China (CN), the United States (U.S.), and Germany (DE). The results highlight pronounced regional differences and different temporal dynamics. Today, CN exhibits substantially higher cradle-to-gate impacts in acetic acid production compared to the U.S. and DE, primarily driven by upstream coal-based methanol production. Under 2025 electricity mixes, CO2-derived methanol and CO pathways result in higher cradle-to-gate impacts than fossil routes for CN and U.S., primarily due to energy-intensive electrolysis and carbon capture. However, when renewable electricity is used for water electrolysis in H2 production, CO2-based acetic acid production can already outperform fossil-derived pathways in the near term. This effect is more pronounced for CO2 sourced via direct air capture (DAC) compared to carbon capture and utilization (CCU) from flue gas streams. Under projected 2035–2050 energy transitions, CO2-based feedstocks outperform fossil pathways across all regions even with grid-powered electrolysis, becoming the environmentally preferred option. Prospective analyses indicate that power-sector decarbonization and CO2-based feedstocks can reduce climate change impacts in acetic acid production to as low as –1.30 kg CO2 equiv/kg acetic acid with CO2 from DAC in DE by 2050. However, the exact environmental benefits of CO2-based raw materials vary by region due to differences in the decarbonization of regional power grids. These insights underscore the potential of CO2-based feedstocks for acetic acid production as a viable decarbonization strategy for the chemical industry as the energy system transitions toward low-carbon power.