Towards improving the sustainability of bioplastics: Process modelling and life cycle assessment of two separation routes for 2,5-furandicarboxylic acid

Abstract

Within the framework of an economy excessively dependent on fossil resources, the concept of sustainable development, aimed at obtaining environmentally friendly consumer goods, has given rise to the development of biorefineries. These facilities are based on the production of biofuels and platform chemicals from the most abundant raw material on the planet: biomass. The use of biomass such as wood or lignocellulosic residues makes it possible to seize opportunities offered by the implementation of renewable feedstocks, which in many cases can be embedded within the perspective of circular economy, through the exploitation of residual fractions. Among the multiple basic chemicals that can be obtained from biomass, 2,5-furandicarboxylic acid (FDCA) has a great potential, as it is the precursor of poly(ethylene furanoate) (PEF) polymer, which is considered a feasible substitute for poly(ethylene terephthalate) (PET). The purpose of this study is the simulation and environmental analysis of two separation routes for FDCA production with the objective of identifying the environmental hotspots at an early stage of the process design. The present study addresses the modelling of FDCA production from hydroxymethyl furfural (HMF) by heterogeneous catalysis using commercial Aspen Plus® V9 software. Two different downstream separation options resulting in purified FDCA were simulated: crystallization (Scenario A) and distillation (Scenario B). The estimation of the mass and energy balances were considered in the development of the data inventories required to conduct Life Cycle Assessment (LCA). LCA-assisted decision making identifies the conceptual configuration that would eventually lead to the least environmental burden. In the case of Scenario A, the stage with the highest environmental burden was the reaction unit, due to the use of HMF. In Scenario B, on the other hand, the separation stages contributed most to the impact due to their high energy demand. The combination of process simulation and LCA allowed acquiring a detailed vision of the process, through the analysis of the sensitivity of the environmental profile to different process parameters. The operating pressure in flash and distillation units for both scenarios affects plant operation by influencing total energy consumption and FDCA production. The sensitivity of environmental outcomes to these parameters was also studied, resulting in small variations. Thus, the results of this assessment provide strategic information of the early decision-making process on potential configurations for industrial-scale FDCA production