Life cycle assessment of priority biochemicals: A review and meta-regression analysis

Compared to traditional petrochemicals, biochemicals have the potential to reduce greenhouse gas (GHG) emissions and energy consumption throughout their life cycle. Life cycle assessment (LCA) has been widely used to assess the potential environmental impacts of biochemicals. However, the diversity in biorefinery configurations (e.g., the choice of feedstocks, platforms, and conversion processes) and LCA modeling assumptions (e.g., functional units, system boundary, and allocation methods) all affect the estimated environmental impact results of biochemicals, leading to large uncertainties in understanding their environmental benefits. Our research provides a comprehensive review of the current refinery routes and their associated climate change impacts for 17 priority biochemicals from published LCA studies. We collected their Global Warming Potential (GWP) results and employed a system harmonization approach to minimize variations in LCA modeling assumptions. The results showed that most biochemicals exhibited lower GWP results compared to their petrochemical counterparts, mainly due to the carbon sequestration credit through biomass growth and reduced GHG emissions during the chemical manufacturing processes. In addition, our meta-regression analysis showed that the variation in biorefinery feedstock types was the primary contributor to the variability in biochemical GWP results.