Editor's Note

On April 9, the Overseas Edition of People's Daily (Page 10) published an article titled "Chinese Academy of Sciences team achieves breakthrough - achieving efficient decomposition and transformation of waste plastics", which introduced the latest research results on the use of microwaves to treat waste plastics published in the international academic journal Nature Communications by Ma Wangjing and others from the Oil and Gas Development Center of the Institute of Physical Chemistry and Chemistry of the Chinese Academy of Sciences in cooperation with Tsinghua University, Oxford University and other universities.

Recycling waste plastics is helpful for environmental restoration and the development of related industries, but existing technologies make it difficult to directly recycle contaminated mixed waste plastics, which need to be sorted, cleaned and pre-treated before recycling. The pretreatment process is costly, time-consuming and energy-intensive, and the recycled plastics usually result in reduced quality. Compared with plastic recycling, the strategy of upgrading and reusing waste mixed plastics brings hope for their management and value-added utilization, and can directly convert waste mixed plastics into olefin monomers and other value-added chemicals. However, existing methods have problems such as high energy consumption, precious metal involvement, high pressure and low catalyst stability. In particular, it is currently impossible to directly upgrade and recycle landfill mixed waste plastics with high impurity content. Therefore, the economical, low-cost and efficient utilization of mixed waste plastics that have not been separated and treated has become the key to solving white pollution. Recently, a scientific research team focusing on solid waste treatment has achieved a series of breakthrough results, opening up a new path for the treatment of waste plastics.

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The Chinese Academy of Sciences team has achieved remarkable results

Ma Wangjing and others from the Oil and Gas Development Center of the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences, together with Tsinghua University, Oxford University and other universities, have successfully achieved the efficient decomposition and transformation of mixed waste plastics in landfills through the innovative use of microwave technology , turning waste plastics into high-value-added chemical raw materials and fuels, which not only greatly improved resource utilization, but also significantly reduced environmental pollution caused by traditional treatment methods. In addition, the research team of the Institute of Physics and Chemistry has published a number of research results in other professional journals on the use of microwave treatment to recycle waste such as polyolefin plastics, agricultural and forestry waste, polyurethane, bioethanol, etc., further improving the theoretical and practical system of microwave treatment technology for different types of waste and different application scenarios. These studies elaborated on the mechanism of interaction between microwaves and organic molecules, optimized the processing parameters, and laid a solid foundation for the large-scale industrial application of this technology. Relying on its profound technical accumulation in the field of waste plastic processing, the Institute of Physics and Chemistry team has deployed a systematic patent system, covering multiple key links such as the design and manufacture of microwave processing equipment, optimization and control of processing technology, product separation and purification, forming a complete intellectual property protection system.

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Microwave treatment of waste plastics

the research team of the Institute of Physics and Chemistry designed and synthesized a zinc cluster/zinc oxide composite catalyst with strong microwave absorption and high catalytic activity by using a simple and economical in-situ construction method. The study achieved the selective and directional transmission of microwave energy to the catalyst in a low-power microwave field, depolymerizing and upgrading mixed waste plastics and agricultural films from landfills into olefin monomers and base lubricant precursors. At the same time, thanks to the excellent chemical bond activation ability of Zn atomic clusters, the electric field enhancement of atomic cluster metal sites, and the synergistic catalytic effect of zinc clusters/zinc oxide, the study achieved the selective depolymerization of mixed waste plastics at 280°C, normal pressure, and mild conditions as low as 1/8 of the traditional thermal catalytic energy consumption, and the catalytic performance was better than that of most precious metal catalysts. In particular, the strong breaking ability of zinc clusters/zinc oxide on the CH and CC bonds of polyolefin plastics under mild conditions inhibited the formation of carbon deposits, giving the zinc cluster/zinc oxide catalyst good stability and a plastic depolymerization turnover number of 250 gplastic g-1catalyst.

Study proposes microwave-driven catalytic recycling of waste plastics for "value-added" utilization

The study reported a strategy for the "value-added" utilization of contaminated waste plastics in landfills by microwave-assisted zinc/zinc oxide enhanced catalysis, which provides new ideas for the economical and low-energy chemical recycling and upgrading of mixed waste plastics and other polymers that are traditionally difficult to recycle, such as agricultural and forestry biowaste and waste fibers. Recently, the relevant research results were published in Nature Communications under the title of Highly selective upcycling of plastic mixture waste by microwave-assisted catalysis over Zn/b-ZnO. The research work was supported by the National Natural Science Foundation of China and the Chinese Academy of Sciences.

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The technology has officially entered the stage of industrialization and promotion

Green water and green mountains are gold and silver mountains. Waste recycling is a key link in promoting green development and building a beautiful China. With the acceleration of industrialization and urbanization, the treatment of waste plastics has become more urgent and has become an important topic in the field of ecological environment protection and resource recycling. At the 2025 Zhongguancun Forum Annual Meeting, the research team of the Institute of Chemistry of the Chinese Academy of Sciences signed a transfer agreement with relevant companies on this series of patents, with the transfer amount reaching 20 million yuan . This signing is not only a recognition of the team's scientific research results, but also marks that the microwave treatment of waste plastics technology will officially move towards the stage of industrialization and promotion . Through in-depth cooperation with enterprises, it is expected to accelerate the implementation of technology, promote the transformation and upgrading of the waste plastic treatment industry, and achieve a win-win situation of economic and environmental benefits. As an important part of the waste recycling system, waste plastic treatment is of great significance to reducing environmental pollution, saving resources, and promoting green and low-carbon development. In the future, with the widespread application of microwave treatment technology, it is expected to provide innovative solutions to the problem of waste plastic treatment in China and even the world, and help achieve the "dual carbon" goal.