Roux Megan, Varrone Cristiano
Section for Sustainable Biotechnology, Department of Chemistry and BioScience, Aalborg University, A. C. Meyers Vænge 15, C2, 2450 Copenhagen, Denmark.
Polymers (Basel). 2021 Nov 10;13(22):3883. doi: 10.3390/polym13223883.
It is widely accepted that plastic waste is one of the most urgent environmental concerns the world is currently facing. The emergence of bio-based plastics provides an opportunity to reduce dependency on fossil fuels and transition to a more circular plastics economy. For polyethylene terephthalate (PET), one of the most prevalent plastics in packaging and textiles, two bio-based alternatives exist that are similar or superior in terms of material properties and recyclability. These are polyethylene furanoate (PEF) and polytrimethylene terephthalate (PTT). The overarching aim of this study was to examine the transition from fossil-based to renewable plastics, through the lens of PET upcycling into PEF and PTT. The process for the production of PEF and PTT from three waste feed streams was developed in the SuperPro Designer software and the economic viability assessed via a discounted cumulative cash flow (DCCF) analysis. A techno-economic analysis of the designed process revealed that the minimum selling price (MSP) of second generation-derived PEF and PTT is 3.13 USD/kg, and that utilities and the feedstock used for the production of 2,5-furandicarboxylic acid (FDCA) needed in PEF synthesis contributed the most to the process operating costs. The effect of recycling PEF and PTT through the process at three recycling rates (42%, 50% and 55%) was investigated and it was revealed that increased recycling could reduce the MSP of the 2G bio-plastics (by 48.5%) to 1.61 USD/kg. This demonstrates that the plastic biorefinery, together with increasing recycling rates, would have a beneficial effect on the economic viability of upcycled plastics.
塑料垃圾是当前世界面临的最紧迫的环境问题之一，这一点已得到广泛认可。生物基塑料的出现为减少对化石燃料的依赖以及向更循环的塑料经济转型提供了契机。对于聚对苯二甲酸乙二酯（PET）这种包装和纺织品中最常见的塑料之一，存在两种生物基替代品，它们在材料性能和可回收性方面相似或更优。这两种替代品是聚呋喃二甲酸乙二酯（PEF）和聚对苯二甲酸丙二酯（PTT）。本研究的总体目标是通过将PET升级循环为PEF和PTT的视角，审视从化石基塑料向可再生塑料的转变。在SuperPro Designer软件中开发了由三种废物流生产PEF和PTT的工艺，并通过折现累计现金流（DCCF）分析评估了其经济可行性。对所设计工艺的技术经济分析表明，第二代衍生的PEF和PTT的最低售价（MSP）为3.13美元/千克，并且公用事业以及用于PEF合成所需的2,5 - 呋喃二甲酸（FDCA）生产的原料对工艺运营成本贡献最大。研究了以三种回收率（42%、50%和55%）通过该工艺回收PEF和PTT的效果，结果表明回收率提高可将第二代生物塑料的MSP降低48.5%至1.61美元/千克。这表明塑料生物精炼厂以及提高回收率将对升级循环塑料的经济可行性产生有益影响。
