Enzymes’ Power for Plastics Degradation

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(9), P. 5612 - 5701

Published: March 14, 2023

Plastics are everywhere in our modern way of living, and their production keeps increasing every year, causing major environmental concerns. Nowadays, the end-of-life management involves accumulation landfills, incineration, recycling to a lower extent. This ecological threat environment is inspiring alternative bio-based solutions for plastic waste treatment toward circular economy. Over past decade, considerable efforts have been made degrade commodity plastics using biocatalytic approaches. Here, we provide comprehensive review on recent advances enzyme-based biocatalysis design related processes recycle or upcycle plastics, including polyesters, polyamides, polyurethanes, polyolefins. We also discuss scope limitations, challenges, opportunities this field research. An important message from that polymer-assimilating enzymes very likely part solution reaching

Language: Английский

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Polyolefins and Polystyrene as Chemical Resources for a Sustainable Future: Challenges, Advances, and Prospects

ACS Materials Letters, Journal Year: 2021, Volume and Issue: 3(12), P. 1660 - 1676

Published: Oct. 29, 2021

Nonbiodegradable plastics with inert and saturated C–C backbones comprise the majority of global annual produced, including ubiquitous polyolefins (polyethylene polypropylene) polystyrene. Unlike polymers cleavable bonds, such as polyesters, polyurethanes, polycarbonates, these are most challenging to upcycle cannot be easily broken down by chemical or enzymatic means. Thus, they mostly end up in landfills incinerated produce copious amounts greenhouse emissions. In recent years, increased research effort has been focused toward upcycling low-value plastic waste give them a new lease life. However, unreactive polymer have posed formidable challenges for attempts at post-synthetic functionalization conversion into commodity chemicals. this Perspective, we discuss large untapped resources production functional polymeric materials valuable industrially relevant feedstock, dicarboxylic acids aromatic compounds. The exciting pioneering work featured herein will hopefully inspire change way view from dead-end versatile raw materials, forming basis more sustainable economy.

Language: Английский

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Chemically recyclable polymer materials: polymerization and depolymerization cycles

Green Chemistry, Journal Year: 2022, Volume and Issue: 24(6), P. 2321 - 2346

Published: Jan. 1, 2022

The design and synthesis of chemically recyclable polymers, which can be reutilized as their starting monomers or new value-added chemicals, has provided a practical approach to address the end-of-use problem polymer materials possible closed-loop method for material usage. More more attention been paid exhibit an increasing prominent role in sustainable development. Nowadays, polymers including polyesters, polythioesters, polycarbonates, polyacetals, polyamides, so on have made significant achievements. Consequently, this minireview summarizes examples achieving polymerization–depolymerization cycle access are categorized into seven parts based monomers.

Language: Английский

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Converting waste PET plastics into automobile fuels and antifreeze components

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: June 10, 2022

With the aim to solve serious problem of white plastic pollution, we report herein a low-cost process quantitatively convert polyethylene terephthalate (PET) into p-xylene (PX) and ethylene glycol (EG) over modified Cu/SiO2 catalyst using methanol as both solvent hydrogen donor. Kinetic in-situ Fourier-transform infrared spectroscopy (FTIR) studies demonstrate that degradation PET PX involves tandem methanolysis dimethyl (DMT) selective hydro-deoxygenation (HDO) steps with produced H2 from decomposition at 210 °C. The overall high activities are attributed Cu+/Cu0 ratio derived dense granular copper silicate precursor, formed by induction proper NaCl addition during hydrothermal synthesis. This hydrogen-free one-pot approach allows directly produce gasoline fuels antifreeze components waste poly-ester plastic, providing feasible solution in islands.

Language: Английский

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Chemical Recycling of Polyethylene by Tandem Catalytic Conversion to Propylene

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(40), P. 18526 - 18531

Published: Sept. 30, 2022

Although polyethylene (PE) and polypropylene (PP) are by far the world's largest volume plastics, only a tiny fraction of these energy-rich polyolefins currently recycled. Depolymerization PE to its constituent monomer, ethylene, is highly endothermic conventionally accessible through unselective, high-temperature pyrolysis. Here, we provide experimental demonstrations our recently proposed tandem catalysis strategy, which uses ethylene convert propylene, commodity monomer used make PP. The approach combines rapid olefin metathesis with rate-limiting isomerization. Monounsaturated progressively disassembled at modest temperatures via many consecutive ethenolysis events, resulting selectively in propylene. Fully saturated can be converted unsaturated starting single transfer dehydrogenation produces small amount ethane (1 equiv per event). These principles demonstrated using both homogeneous heterogeneous catalysts. While selectivity under batch conditions limited high conversion formation an equilibrium mixture olefins, propylene (≥94%) achieved semicontinuous process due continuous removal from reaction mixture.

Language: Английский

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Recommendations for replacing PET on packaging, fiber, and film materials with biobased counterparts

Green Chemistry, Journal Year: 2021, Volume and Issue: 23(22), P. 8795 - 8820

Published: Jan. 1, 2021

This review sheds light on urgent questions that arise from the need to replace a polymer resin,–poly(ethylene terephthalate), which represents 7.7% market-share in global plastic demand (Plastics–the Facts 2019), by renewable alternatives. The main question this will address is: what are most promising PET replacements made biomass? Currently, under debate is naturally its biobased counterpart bio-PET (or even recycle rPET), as well other aromatic key-players with comparable thermo-mechanical performance and enhanced barrier properties, such poly(ethylene 2,5-furandicarboxylate) (PEF) poly(trimethylene (PTF). They adequate for packaging, but not restricted to. Additional alternatives miscellaneous of lignin-based thermoplastic polymers, although technology involved latter case still premature. (Bio)degradable aliphatic polyesters, despite their typical inferior can also play role e.g., among fiber industry applications. Poly(lactic acid) (PLA) developed polyester, already commercial reality. All polymers reviewed face major hindrance wider deployment cost-competitiveness. A pertinent arises then: Are these alternatives, or they be, economically feasible? Social, political legal frameworks together supportive financial schemes boosting rapid changes. In future, probably more than one come market be used some panoply evaluation overviews sustainability issues, including perspectives green synthesis. Moreover, does neglect accumulation plastics waste environment inherent challenges polymers' end-of-life. Approximately 8 M tons leaks into each year, fact disconnected PET's non-biodegradability insufficient collection recycling rates.

Language: Английский

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Polymers without Petrochemicals: Sustainable Routes to Conventional Monomers

Chemical Reviews, Journal Year: 2022, Volume and Issue: 123(5), P. 2609 - 2734

Published: Oct. 13, 2022

Access to a wide range of plastic materials has been rationalized by the increased demand from growing populations and development high-throughput production systems. Plastic at low costs with reliable properties have utilized in many everyday products. Multibillion-dollar companies are established around these materials, each polymer takes years optimize, secure intellectual property, comply regulatory bodies such as Registration, Evaluation, Authorisation Restriction Chemicals Environmental Protection Agency develop consumer confidence. Therefore, developing fully sustainable new material even slightly different chemical structure is costly long process. Hence, common exactly same structures that does not require any registration processes better reflects reality how address critical future plastics. In this review, we highlighted very recent examples on synthesis monomers using chemicals feedstocks can be used like-for-like substitute prepare conventional petrochemical-free thermoplastics.

Language: Английский

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Microplastic materials in the environment: Problem and strategical solutions

Progress in Materials Science, Journal Year: 2022, Volume and Issue: 132, P. 101035 - 101035

Published: Oct. 19, 2022

Language: Английский

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Thermochemical Conversion of Plastic Waste into Fuels, Chemicals, and Value‐Added Materials: A Critical Review and Outlooks

ChemSusChem, Journal Year: 2022, Volume and Issue: 15(11)

Published: March 29, 2022

Plastic waste is an emerging environmental issue for our society. Critical action to tackle this problem upcycle plastic as valuable feedstock. Thermochemical conversion of has received growing attention. Although thermochemical promising handling mixed waste, it typically occurs at high temperatures (300-800 °C). Catalysts can play a critical role in improving the energy efficiency conversion, promoting targeted reactions, and product selectivity. This Review aims summarize state-of-the-art catalytic conversions various types waste. First, general trends recent development including pyrolysis, gasification, hydrothermal processes, chemolysis into fuels, chemicals, value-added materials were reviewed. Second, status quo commercial implementation was summarized. Finally, current challenges future perspectives design sustainable robust catalysts discussed.

Language: Английский

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Peroxymonosulfate catalytic degradation of persistent organic pollutants by engineered catalyst of self-doped iron/carbon nanocomposite derived from waste toner powder

Separation and Purification Technology, Journal Year: 2022, Volume and Issue: 291, P. 120963 - 120963

Published: March 31, 2022

Language: Английский

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