Techno-economic assessment of bio-based routes for acrylic acid production†

This work evaluates the techno-economic performance of biobased and conventional routes for producing acrylic acid, a key industrial chemical. Four pathways were assessed at 79.2 ktonnes per year production capacity: three glycerol-based routes (via allyl alcohol, lactic acid, and acrolein) and the conventional propylene-based route. Key performance indicators related to acrylic acid yield, energy consumption, CO₂ emissions, and raw material usage, as well as capital expenditure, OPEX, profitability, and payback period were compared. Among the glycerol-based routes, the lactic acid intermediate route had the highest carbon conversion efficiency (80%), followed by the alcohol intermediate route (74%). From an environmental perspective, propylene-based and glycerol-based allyl alcohol intermediate routes had the highest direct CO₂ emissions, whereas the glycerol-based acrolein intermediate route had the lowest CO₂ emissions. Regarding costs, the glycerol-based allyl alcohol route had the highest capital investment ($247.7 million), while the acrolein route required the lowest ($173.6 million). Moreover, the glycerol-based acrolein intermediate route was the only profitable pathway ($21.6 million annually) but with a commercially unattractive payback period of 11.6 years. Sensitivity analyses revealed that the propylene-based route was the most vulnerable to changes in raw material prices, whereas the acrolein intermediate route was the most resilient to price fluctuations in raw material and utilities, maintaining profitability until a 25% increase in raw material prices. The findings suggest that the renewable glycerol-based acrolein intermediate route can be a promising alternative to conventional acrylic acid production, supporting a transition towards a more sustainable bio-based chemical industry.