We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Single Step Depolymerization of Multiple Polyesters in Poly(Lactic Acid) Mixed Plastics: Process Optimization, Pure Monomers Extraction and Kinetics Evaluation
AI summary Read the abstract
Researchers developed an optimized single-step, non-catalyzed hydrolysis process that simultaneously breaks down mixed PLA and PET plastics into recoverable monomers — lactic acid and terephthalic acid — achieving 83–100% conversion within 30 minutes at 85°C while regenerating waste reagents for reuse in subsequent cycles.
Abstract Nowadays, most of the chemical recycling approaches for plastic waste aim primarily for the depolymerization of single polymer plastics or the multiple steps depolymerization of a plastic mixture which in both cases is considered time, cost and energy consuming. Herein, we present an optimized, single step approach for non-catalyzed hydrolysis of multiple polyesters in Poly(lactic acid) (PLA) mixed plastics under mild conventional heating. The proposed depolymerization process simultaneously breaks down plastic polyesters (mainly PLA and polyethylene terephthalate (PET)) into their value-added monomers; lactic acid in the form of Ca lactate and terephthalic acid (TPA) which are further separated and purified in a reduced number of steps. Box-Behnken Design was employed to maximize the conversion of plastics and the yields of the produced monomers through optimization of the depolymerization and monomer extraction conditions, all while adhering to the green chemistry principles. Within 30 min, and at 85 ⁰C temperature, the proposed hydrolysis technique facilitated 83–100% conversion of various PLA products (PLA Polymaker fibers (containing PLA, PET and other additives), PLA pellets and postconsumer PLA cups) into 763.8-929.6 mg/g plastic Ca lactate and 51.5 mg/g plastic TPA if PET was present. The proposed non-catalyzed process followed first order reaction kinetics with a small activation energy of 78.92 kJ/mol, resulting in an acceptable total energy consumption of 176.0 kJ/g plastic . The obtained monomers’ identity and purity were confirmed by FTIR analysis. Additionally, the waste reagents produced during the depolymerization and monomer extraction processes were regenerated for reuse in another cycle of depolymerization while maintaining good performance. The developed approach offers an economically attractive and ecologically sustainable solution for energy and cost-efficient recycling and upcycling of post-consumer plastic waste containing PLA combined with other polyesters.
More Papers Like This
Synergistic Dual Catalytic System and Kinetics for the Alcoholysis of Poly(Lactic Acid)
AI summary Read the abstract
Researchers developed an improved chemical recycling process using a dual catalyst system to break down polylactic acid (PLA), a common bioplastic, back into reusable building blocks. The approach could improve the circularity of bioplastics and reduce plastic waste from packaging and disposable products.
There and Back Again: Recovery of Terephthalic Acid from Enzymatically Hydrolyzed Polyesters for Resynthesis
AI summary Read the abstract
Researchers demonstrated that enzymes can break down PET plastic and the biodegradable plastic PBAT, recovering the building block terephthalic acid at high purity for reuse in making new plastics. The enzymatic approach worked even on mixed real-world plastic waste, offering an environmentally friendly alternative to chemical or mechanical recycling. The recovered monomer was successfully used to synthesize new polymer, supporting a circular approach to plastic materials.
Depolymerization and Re/Upcycling of Biodegradable PLA Plastics
AI summary Read the abstract
"This review examines chemical depolymerization and re/upcycling strategies for polylactic acid (PLA), the most widely used biodegradable plastic, which despite its sustainability credentials suffers from low recycling rates and high costs. Researchers highlight recent advances and technical barriers in closed-loop chemical recycling as urgently needed alternatives to simple degradation of PLA into CO2 and water."
Upcycling of waste polyesters for the development of a circular economy
AI summary Read the abstract
This review surveys emerging chemical recycling and upcycling technologies for waste polyesters, particularly PET, covering thermal, photocatalytic, electrocatalytic, and biocatalytic depolymerization methods that convert plastic waste back into valuable monomers and chemicals to support a circular carbon economy.
Chemical Recycling of Polyethylene Terephthalate: A Review
AI summary Read the abstract
This review surveys advances in chemical recycling of polyethylene terephthalate (PET)—including glycolysis, hydrolysis, enzymatic depolymerization, and tandem catalysis—as strategies to recover monomers and close the plastic carbon loop. Since PET is a major source of microplastic pollution through bottle and textile degradation, effective chemical recycling pathways are critical for reducing its long-term environmental persistence.
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.