(587e) Economic and Environmental Assessment for the Production of Propylene Glycol from Biodiesel Glyceroleconomic and Environmental Assessment for the Production of Propylene Glycol from Biodiesel Glycerol

Different countries around the world are implementing policies and legislations to promote the sustainable development of their economy (i.e. bioeconomy). Biofuels have been one of the most promoted areas in the transition towards sustainable schemes and many regulations seek their industrialization and commercialization. As a result, over the last years biodiesel production has gained track in the market, resulting in large amounts of waste glycerol being generated as low-cost and readily available feedstock.

Focusing on the enhancement of the bioeconomy and the valorization of biodiesel glycerol, we here address the economic and environmental assessment under uncertainty for different routes in the production of propylene glycol from biodiesel glycerol. More precisely, we compare three different hydrogenolysis routes based on the use of biodiesel glycerol between themselves and against the business as usual process, which uses oil-based propylene oxide as raw material. Using commercial simulators, an initial case for each alternative was first implemented and then optimized through standard heuristics, sensitivity analysis and heat integration. The economic performance was quantified using the economic potential and total annualized cost, while the environmental impact was assessed following Life Cycle Assessment principles using the methodology CML 2001. Finally, the main uncertainties affecting the calculations were evaluated via stochastic modelling.

The results revealed that there are glycerol-based alternatives that outperform the current propylene glycol process simultaneously in terms of profit and environmental impact (i.e. 90% increment in profit and 74% reduction in environmental impact at optimum process conditions).

Overall, our results aim to promote the development of sustainable biorefinery schemes to convert waste glycerol into high-value commodity chemicals, like propylene glycol, within the context of holistic bioeconomy frameworks.