Lomwongsopon Passanun, Martínez Belén Monje, Jiménez Alberto Barranca, Bardenstein Alexander Leo, Kusano Yukihiro, de Claville Christiansen Jesper, Varrone Cristiano
Section of Bioresources and Process Engineering, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg, Denmark.
AIMPLAS, Instituto Technológico del Plástico, València Parc Tecnològic, C/Gustave Eiffel 4, 46980, Paterna, Valencia, Spain.
Chemosphere. 2025 Mar;373:144151. doi: 10.1016/j.chemosphere.2025.144151. Epub 2025 Jan 29.
Polyolefins (PO) are the most common consumer plastics, constituting about half of plastic waste. This work investigated the process combining physicochemical pretreatment and PO-enriched mixed microbial consortia (MMCs) on biodegrading European real mixed plastic waste. The MMCs, acclimatized on PO powders, were enriched with strains that could use PO, primarily dominated by the genus Rhodanobacter. Several pretreatment methods were investigated on pure polyethylene (PE) and polypropylene (PP). UVC combined with Fenton's reagent was found to be the best pretreatment process for pure PO, increasing the total oxidative indices of PE and PP by 135 and 21 times, respectively, and decrease the total crystallinity of PP by 2.3 times (but not PE), compared to the untreated ones. Maximum 7.7% and 16.3% weight reductions were achieved after MMCs biodegradation of UVC-Fenton-treated PE and PP powders (80 μm), with a 4.3- and 27.2-times improvement from the untreated ones. Selected pretreatments and MMCs were then applied to real mixed plastic waste and post-consumer multilayers from 10 different streams. The highest weight reductions after 30-days biodegradation were obtained using mixed plastic reject from a biogas plant (MW2) followed by the unrecyclable mixed plastic waste from a Danish municipality (MW1), with a reduction of 36.8% and 30.0% using radio frequency (RF) oxygen plasma pretreatment, respectively. Integration of ultrasonic irradiation with atmospheric pressure plasma treatment increased the biodegradation of MW1 to 39.4%. This study addressed the bottleneck of slow biodegradation of recalcitrant plastics, laying down the basis for future development of biotechnological recycling of unrecyclable plastic fractions.
聚烯烃（PO）是最常见的消费塑料，约占塑料垃圾的一半。本研究调查了物理化学预处理与富含PO的混合微生物群落（MMC）相结合对欧洲真实混合塑料垃圾进行生物降解的过程。在PO粉末上驯化的MMC富含能够利用PO的菌株，主要以红杆菌属为主。对纯聚乙烯（PE）和聚丙烯（PP）研究了几种预处理方法。发现紫外线（UVC）与芬顿试剂联合使用是纯PO的最佳预处理工艺，与未处理的相比，PE和PP的总氧化指数分别提高了135倍和21倍，PP的总结晶度降低了2.3倍（但PE未降低）。经MMC对UVC - 芬顿处理的PE和PP粉末（80μm）进行生物降解后，重量分别最大降低了7.7%和16.3%，与未处理的相比提高了4.3倍和27.2倍。然后将选定的预处理方法和MMC应用于来自10种不同来源的真实混合塑料垃圾和消费后多层塑料。使用沼气厂的混合塑料废料（MW2）进行30天生物降解后重量减少最多，其次是丹麦一个城市的不可回收混合塑料垃圾（MW1），使用射频（RF）氧等离子体预处理时，重量分别减少了36.8%和30.0%。超声辐照与大气压等离子体处理相结合将MW1的生物降解率提高到了39.4%。本研究解决了难降解塑料生物降解缓慢的瓶颈问题，为未来不可回收塑料组分的生物技术回收发展奠定了基础。
