Catalytic Amination of Polylactic Acid to Alanine DOI

Shuheng Tian,

Yuchen Jiao,

Zirui Gao

et al.

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(40), P. 16358 - 16363

Published: Sept. 30, 2021

In comparison to the traditional petroleum-based plastics, polylactic acid, most popular biodegradable plastic, can be decomposed into carbon dioxide and water in environment. However, natural degradation of acid requires a substantial period time and, more importantly, it is carbon-emitting process. Therefore, highly desirable develop novel transformation process that upcycle plastic trash value-added products, especially with high chemical selectivity. Here we demonstrate one-pot catalytic method convert alanine by simple ammonia solution treatment using Ru/TiO2 catalyst. The has 77% yield at 140 °C, an overall selectivity 94% reached recycling experiments. Importantly, no added hydrogen used this It been verified lactamide ammonium lactate are initial intermediates dehydrogenation initiates amination, while Ru nanoparticles essential for dehydrogenation/rehydrogenation amination steps. demonstrated here could expand application waste inspire new upcycling strategies different wastes.

Language: Английский

Machine learning-aided engineering of hydrolases for PET depolymerization DOI
Hongyuan Lu, Daniel J. Diaz, Natalie J. Czarnecki

et al.

Nature, Journal Year: 2022, Volume and Issue: 604(7907), P. 662 - 667

Published: April 27, 2022

Language: Английский

Citations

765

Soil structure and microbiome functions in agroecosystems DOI
Martin Hartmann, Johan Six

Nature Reviews Earth & Environment, Journal Year: 2022, Volume and Issue: 4(1), P. 4 - 18

Published: Nov. 22, 2022

Language: Английский

Citations

619

Plastic pollution in the Arctic DOI Creative Commons
Melanie Bergmann, F. Collard, Joan Fabrés

et al.

Nature Reviews Earth & Environment, Journal Year: 2022, Volume and Issue: 3(5), P. 323 - 337

Published: April 5, 2022

Plastic pollution is now pervasive in the Arctic, even areas with no apparent human activity, such as deep seafloor. In this Review, we describe sources and impacts of Arctic plastic pollution, including debris microplastics, which have infiltrated terrestrial aquatic systems, cryosphere atmosphere. Although some from local — fisheries, landfills, wastewater offshore industrial activity distant regions are a substantial source, carried lower latitudes to by ocean currents, atmospheric transport rivers. Once accumulates certain affects ecosystems. Population-level information sparse, but interactions entanglements ingestion marine been recorded for mammals, seabirds, fish invertebrates. Early evidence also suggests between climate change pollution. Even if emissions halted today, fragmentation legacy will lead an increasing microplastic burden ecosystems, already under pressure anthropogenic warming. Mitigation urgently needed at both regional international levels decrease production utilization, achieve circularity optimize solid waste management treatment. microplastics ubiquitous Arctic. This Review describes sources, distribution consequences calls immediate action mitigate further ecosystem impact.

Language: Английский

Citations

413

Achieving net-zero greenhouse gas emission plastics by a circular carbon economy DOI
Raoul Meys, Arne Kätelhön, Marvin Bachmann

et al.

Science, Journal Year: 2021, Volume and Issue: 374(6563), P. 71 - 76

Published: Sept. 30, 2021

Reducing net emission The great majority of plastics in current use are sourced from fossil fuels, with additional fuels combusted to power their manufacture. Substantial research is focused on finding more sustainable building blocks for next-generation polymers. Meys et al . report a series life cycle analyses suggesting that even the varieties commercial monomers could potentially be manufactured and polymerized no greenhouse gas emissions. relies combining recycling plastic waste chemical reduction carbon dioxide captured incineration or derived biomass. —JSY

Language: Английский

Citations

382

Outside the Safe Operating Space of a New Planetary Boundary for Per- and Polyfluoroalkyl Substances (PFAS) DOI Creative Commons
Ian T. Cousins, Jana H. Johansson, Matthew Salter

et al.

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(16), P. 11172 - 11179

Published: Aug. 2, 2022

It is hypothesized that environmental contamination by per- and polyfluoroalkyl substances (PFAS) defines a separate planetary boundary this has been exceeded. This hypothesis tested comparing the levels of four selected perfluoroalkyl acids (PFAAs) (i.e., perfluorooctanesulfonic acid (PFOS), perfluorooctanoic (PFOA), perfluorohexanesulfonic (PFHxS), perfluorononanoic (PFNA)) in various global media rainwater, soils, surface waters) with recently proposed guideline levels. On basis PFAAs considered, it concluded (1) PFOA PFOS rainwater often greatly exceed US Environmental Protection Agency (EPA) Lifetime Drinking Water Health Advisory sum aforementioned (Σ4 PFAS) above Danish drinking water limit values also based on Σ4 PFAS; (2) are Quality Standard for Inland European Union Surface Water; (3) atmospheric deposition leads to soils being ubiquitously contaminated be Dutch values. is, therefore, spread these atmosphere led chemical pollution Levels especially poorly reversible because high persistence their ability continuously cycle hydrosphere, including sea spray aerosols emitted from oceans. Because poor reversibility exposure PFAS associated effects, vitally important uses emissions rapidly restricted.

Language: Английский

Citations

353

The rise of self-driving labs in chemical and materials sciences DOI Open Access
Milad Abolhasani, Eugenia Kumacheva

Nature Synthesis, Journal Year: 2023, Volume and Issue: 2(6), P. 483 - 492

Published: Jan. 30, 2023

Language: Английский

Citations

284

First evidence of microplastics in Antarctic snow DOI Creative Commons
Alex Aves, Laura E. Revell, Sally Gaw

et al.

˜The œcryosphere, Journal Year: 2022, Volume and Issue: 16(6), P. 2127 - 2145

Published: June 7, 2022

Abstract. In recent years, airborne microplastics have been identified in a range of remote environments. However, data throughout the Southern Hemisphere, particular Antarctica, are largely absent to date. We collected snow samples from 19 sites across Ross Island region Antarctica. Suspected microplastic particles were isolated and their composition confirmed using micro-Fourier transform infrared spectroscopy (µFTIR). all Antarctic at an average concentration 29 L−1, with fibres most common morphotype polyethylene terephthalate (PET) polymer. To investigate sources, backward air mass trajectories run time sampling. These indicate potential long-range transportation up 6000 km, assuming residence 6.5 d. Local sources also as inputs into environment polymers consistent those used clothing equipment nearby research stations. This study adds growing body literature regarding ubiquitous pollutant establishes presence

Language: Английский

Citations

281

Hemicellulose: Structure, chemical modification, and application DOI
Jun Rao,

Ziwen Lv,

Gegu Chen

et al.

Progress in Polymer Science, Journal Year: 2023, Volume and Issue: 140, P. 101675 - 101675

Published: March 13, 2023

Language: Английский

Citations

244

Why is Recycling of Postconsumer Plastics so Challenging? DOI
Bryan D. Vogt, Kristoffer K. Stokes, Sanat K. Kumar

et al.

ACS Applied Polymer Materials, Journal Year: 2021, Volume and Issue: 3(9), P. 4325 - 4346

Published: Aug. 23, 2021

The ubiquitous use of plastics has been driven by their combination low cost and properties, but these attributes directly challenge waste management schemes for plastic recycling. Some postconsumer recycling programs are now nearly 50 years old, a significant fraction still finds landfills or other dumping strategies at end life. With the growing concern regarding waste, especially ocean plastics, there is need innovation alternative economic translation to valued product(s) that will promote efficient circular utilization. This review first describes technical hurdles associated with then it focuses on providing an overview emergent recover through new polymer design, processes, chemical transformations value-added products. Specific challenges discussed include sorting separations, product variability including additives, high efficiency/low in which existing petrochemical industry can produce virgin polymers, particular polyolefins. Although wide variety have demonstrated both mechanical means, commercial success different generally limited either performance, large variance key metrics, economics where products match performance materials process expensive. Successful capture likely depend incentives government regulations.

Language: Английский

Citations

236

Weathering Plastics as a Planetary Boundary Threat: Exposure, Fate, and Hazards DOI Creative Commons
Hans Peter H. Arp, Dana Kühnel, Christoph Rummel

et al.

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(11), P. 7246 - 7255

Published: May 11, 2021

We described in 2017 how weathering plastic litter the marine environment fulfils two of three criteria to impose a planetary boundary threat related "chemical pollution and release novel entities": (1) planetary-scale exposure, which (2) is not readily reversible. Whether plastics meet third criterion, (3) eliciting disruptive impact on vital earth system processes, was uncertain. Since then, several important discoveries have been made motivate re-evaluation. A key issue if macroplastics, microplastics, nanoplastics, their leachates an inherently higher potential elicit adverse effects than natural particles same size. summarize findings context that demonstrate increasing fate processes leading poorly reversible pollution, (eco)toxicological hazards thresholds. provide evidence criterion could be fulfilled for sensitive environments therefore conclude pose threat. suggest future research priorities better understand modulated by exposure continuous parametrize threshold pollution.

Language: Английский

Citations

233