Salah Cecilia, Istrate Robert, Bjørn Anders, Tulus Victor, Pérez-Ramírez Javier, Guillén-Gosálbez Gonzalo
Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland.
Institute of Environmental Sciences (CML), Leiden University, 2333 CC Leiden, The Netherlands.
ACS Sustain Chem Eng. 2024 Sep 3;12(37):13897-13906. doi: 10.1021/acssuschemeng.4c04241. eCollection 2024 Sep 16.
The linear nature of the current plastics economy and increasing demand for polymers poses a pressing global problem. In this work, we explore the environmental and economic performance of a circular alternative for polymer production through chemical plastic recycling following the waste-to-methanol-to-olefins (WMO) route. We assess the life-cycle environmental impacts and techno-economic feasibility of this novel circular production route (CPR) in 2020 and 2050, and compare them to the existing linear production route (LPR), deploying naphtha steam cracking for olefin production, and a mix of landfill and incineration as end-of-life treatment. Our results showcase that CPR could enable significant impact reductions, notably in 2050 assuming a low-carbon electricity mix based on renewables. However, the shift from linear to circular comes with burden-shifting, increasing the impacts relative to LPR on five environmental indicators in 2020 (i.e., terrestrial and freshwater eutrophication, particulate matter formation, acidification, and metal/mineral resources use). From the techno-economic viewpoint, we found that ethylene from waste polymers could become competitive with fossil ethylene when deployed at large scale. Moreover, it is significantly cheaper than its green analogs, which deploy methanol-to-olefins with green methanol from captured CO and electrolytic H, showcasing the potential of implementing high-readiness level technologies to close the loop for polymers.
当前塑料经济的线性本质以及对聚合物不断增长的需求构成了一个紧迫的全球问题。在这项工作中，我们探索了一种通过化学塑料回收利用，遵循废塑料制甲醇制烯烃（WMO）路线的聚合物生产循环替代方案的环境和经济表现。我们评估了这种新型循环生产路线（CPR）在2020年和2050年的生命周期环境影响和技术经济可行性，并将其与现有的线性生产路线（LPR）进行比较，LPR采用石脑油蒸汽裂解生产烯烃，并将填埋和焚烧相结合作为生命周期末端处理方式。我们的结果表明，CPR能够显著减少影响，特别是在2050年，假设基于可再生能源的低碳电力组合。然而，从线性向循环的转变伴随着负担转移，在2020年相对于LPR增加了对五个环境指标的影响（即陆地和淡水富营养化、颗粒物形成、酸化以及金属/矿产资源使用）。从技术经济角度来看，我们发现来自废塑料的乙烯在大规模应用时可能与化石乙烯具有竞争力。此外，它比其绿色类似物便宜得多，绿色类似物使用捕获的二氧化碳和电解氢气生产的绿色甲醇来生产甲醇制烯烃，这展示了实施高成熟度技术以实现聚合物闭环的潜力。
