We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Impact of the thermo-alkaline pretreatment on the anaerobic digestion of poly(butylene adipate-co-terephthalate) (PBAT) and poly(lactic acid) (PLA) blended plastics
AI summary Read the abstract
Researchers tested whether a heat-and-alkali pretreatment could improve the breakdown of biodegradable plastics PBAT and PLA through anaerobic digestion. They found that pretreatment significantly improved methane production from PLA-containing blends but had limited effect on PBAT alone, which remained resistant to digestion. The results suggest that even plastics labeled as biodegradable may not break down easily in real-world composting and waste treatment systems.
Poly(butylene adipate-co-terephthalate) (PBAT) is a biodegradable plastic that is difficult to degrade under both mesophilic and thermophilic anaerobic conditions. In this study, the impact of the thermo-alkaline pretreatment (48 h, 70 °C, 1 % w/v NaOH) on the anaerobic degradation (AD) of PBAT, poly(lactic acid) (PLA) and PBAT/PLA blended plastics was investigated. Under mesophilic conditions, pretreatment only improved the methane yield of PBAT/PLA/starch plastic (100 days, 51 and 34 NmL/g VS for the treated and original plastics, respectively). Under thermophilic conditions, the pretreatment increased the methanogenic rate of PLA, PBAT and PBAT/PLA/starch plastic at the beginning stage (22 days, 35 and 79 NmL/g VS for original and treated PBAT, respectively), but did not change the methane yield at the end of the incubation (100 days, 91 NmL/g VS for original and treated PBAT). The reduction in the molecular weight and the formation of pore structures on the plastic surface accelerated the utilization of plastics by microorganisms. Furthermore, the pretreated plastics tend to form microplastics (MPs) with size predominantly below 500 µm (>90 %). The numbers of MPs dynamically changed with the degradation time. Several genera of bacteria showed specific degradation of biodegradable plastics under thermophilic conditions, including Desulfitibacter, Coprothermobacter, Tepidimicrobium, c_ D8A-2 and Thermacetogenium. The results suggest that more attention should be paid to the problem of MPs arising from the thermo-alkaline pretreatment.
More Papers Like This
Simulation of biowastes and biodegradable plastics co-digestion in semi-continuous reactors: Performances and agronomic evaluation
AI summary Read the abstract
This study looked at whether "biodegradable" plastics (like those in compostable food containers) actually break down when mixed with food waste in biogas facilities. The good news: one type (PHB) fully broke down, while the other (PLA) only partially degraded unless pretreated with a chemical bath first, meaning some biodegradable plastics may not fully disappear during typical waste processing, which matters because leftover plastic fragments could end up in the fertilizer made from this waste and spread on farmland. The upside is that adding either plastic didn't harm the quality of that fertilizer, but the findings suggest not all "biodegradable"
Enhancing Bioplastic Degradation in Anaerobic Digestion: A Review of Pretreatment and Co-Digestion Strategies
AI summary Read the abstract
This review examines strategies to improve the breakdown of bioplastics—including PLA, PHB, and starch-based materials—through anaerobic digestion, finding that pretreatment techniques (mechanical, thermal, and enzymatic) combined with co-digestion of food waste or sewage sludge can significantly boost methane yields and support circular waste management.
Assessing labelled carbon assimilation from poly butylene adipate-co-terephthalate (PBAT) monomers during thermophilic anaerobic digestion
AI summary Read the abstract
Researchers used isotopically labeled carbon to track the biodegradation of PBAT (a biodegradable plastic) monomers in anaerobic conditions using wastewater treatment sludge as inoculum, finding limited metabolization that raises questions about PBAT's true biodegradability in anaerobic environments.
Pretreatment and Anaerobic Co-digestion of Selected PHB and PLA Bioplastics
AI summary Read the abstract
Researchers evaluated thermal and alkaline pretreatments for PHB and PLA bioplastics to enhance anaerobic digestion, finding pretreatment increased biochemical methane potential by over 100% and reduced lag times before methane production. Bench-scale co-digesters fed synthetic primary sludge with PHB achieved 80-98% conversion to biomethane, with a 5% increase in total biomethane output.
Anaerobic Degradation of Aromatic and Aliphatic Biodegradable Plastics: Potential Mechanisms and Pathways.
AI summary Read the abstract
This study examined how biodegradable plastics — PBAT and PLA — break down under anaerobic conditions in digestion systems, finding that microbial communities degrade them through distinct biochemical pathways. Understanding how biodegradable plastics decompose in real-world conditions like landfills and wastewater treatment is important for evaluating whether they truly degrade safely.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.