Integrated Phosgene and Steel Production: Combining Process Optimization and Life Cycle Assessment to Minimize Greenhouse Gas Emissions

Abstract Harnessing basic oxygen furnace gas (BOFG) from steel mills as an alternative carbon source is a promising option to reduce greenhouse gas (GHG) emissions. This study explores two process concepts to purify CO from BOFG for subsequent phosgene synthesis: (i) vacuum pressure swing adsorption (VPSA) yielding pure CO, and (ii) CO 2 separation via monoethanolamine (MEA) absorption producing CO‐enriched gas. By combining process optimization with life cycle assessment (LCA), process parameters are identified that minimize GHG emissions. The MEA concept can reduce emissions by up to 60 %, whereas the VPSA concept achieves a reduction of 47 %. Utilizing renewable energy enables further reductions, indicating additional environmental benefits in the future. Overall, both processes effectively produce low‐carbon CO for phosgene synthesis, with increasing environmental benefits in future energy systems.