Depolymerization of plastics by means of electrified spatiotemporal heating (duplicate PDF registration)
Evidence and attribution¶
Duplicate bytes
pdf_sha256 matches paper:2023dong-nat-depolymerization-plastics; only pdf_path differs (papers/ReaxFF_others/Dong_Lele_plastic_depoly_Nature_2023.pdf vs papers/ReaxFF_others/Dong_Lele_Nature_depolymerization_2023.pdf). Narrative below is duplicated for reader convenience; long-term maintenance may consolidate to one canonical path.
Summary¶
This Nature article (also summarized on [[2023dong-nat-depolymerization-plastics]]) reports catalyst-free thermochemical depolymerization of commodity polypropylene (PP) and poly(ethylene terephthalate) (PET) using electrified spatiotemporal heating (STH). The core idea is to combine a sharp spatial temperature gradient through a bilayer porous carbon felt stack with a pulsed temporal heating profile that reaches high peak temperatures for short intervals, aiming to favor monomer-forming chemistries over slower equilibrium routes that produce more cracked and aromatized side products. This wiki slug exists because the corpus stores an alternate filename for the same SHA-256 bytes. Scientifically, the article is unchanged from [[2023dong-nat-depolymerization-plastics]]: catalyst-free STH depolymerization of PP and PET using a bilayer porous carbon felt reactor with spatial T gradients and pulsed electrical heating, reporting ~36% and ~43% monomer yields respectively in the abstract accounting.
Methods¶
Duplicate-ingest note¶
pdf_sha256 matches [[2023dong-nat-depolymerization-plastics]]; only pdf_path differs. Protocol text below mirrors the primary page for reader convenience.
STH reactor (experimental)¶
Bilayer porous carbon felt stack over a plastic reservoir in a ~10.5 mm quartz tube with Ar carrier gas; spatial T gradient couples melt/wick/vaporize/react; pulsed heating hits peaks ~600 °C (PP discussion) / ~1050 °C (PET schematic) with short on pulses (example 0.11 s on / 0.99 s off).
Analytics¶
Effluent-based yield/selectivity metrics per Nature Methods/Extended Data. The main text motivates STH as far-from-equilibrium pyrolysis: short high-temperature transients (example ~0.11 s on-times paired with ~600 °C peak discussion for PP in the abstract) are intended to enable depolymerization while limiting side reactions that dominate under long isothermal pyrolysis.
Findings¶
PP → propylene ~36% and PET → terephthalic-acid monomer ~43% (authors’ accounting), framed vs conventional pyrolysis baselines in the article; electricity/CO₂ discussion appears in supporting analysis.
Mechanism (as reported): STH couples a bilayer porous carbon felt stack with pulsed Joule heating so plastic melt/wick/vaporize/react along a spatial T gradient while short high-T pulses (example ~0.11 s on at ~600 °C for PP in the abstract discussion) limit time-at-temperature routes that drive deep cracking/aromatization. Sensitivity: monomer yield is expected to track pulse program, felt geometry, and feed—not re-quantified on this duplicate page.
Comparisons: catalyst-free STH monomer yields are contrasted with conventional pyrolysis in the Nature text. No new claims vs [[2023dong-nat-depolymerization-plastics]]—use one wiki page for reader-facing prose to avoid duplicate chunks. Limitations & outlook (authored): scale-up, feed variability, and collection/sorting remain open engineering questions beyond the lab demonstration; however the article still positions STH as a lever for waste plastics valorization when renewable electricity is available.
Index hygiene: downstream retrieval jobs should deduplicate by DOI and prefer paper:2023dong-nat-depolymerization-plastics for canonical chunks, keeping this slug only when manifest hash provenance requires the alternate pdf_path. Corpus honesty: same content as [[2023dong-nat-depolymerization-plastics]].
Limitations¶
Yields depend on the specific pulse programme and reactor geometry; scale-up and feed variability require engineering validation. Automation pipelines should treat the two pdf_path values as identical content unless the manifest changes.
Relevance to group¶
Provenance duplicate for a Lele-linked Nature plastics STH article tracked in this corpus.