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Increasing the stream of recycled plastic necessitates an approach beyond the traditional recycling via melting and re‐extrusion. Various chemical recycling processes have great potential to enhance recycling rates. In this Review, a summary of the various chemical recycling routes and assessment via life‐cycle analysis is complemented by an extensive list of processes developed by companies active in chemical recycling. We show that each of the currently available processes is applicable for specific plastic waste streams. Thus, only a combination of different technologies can address the plastic waste problem. Research should focus on more realistic, more contaminated and mixed waste streams, while collection and sorting infrastructure will need to be improved, that is, by stricter regulation. This Review aims to inspire both science and innovation for the production of higher value and quality products from plastic recycling suitable for reuse or valorization to create the necessary economic and environmental push for a circular economy., Plastic fantastic: Plastic can rise again and again as a new product. Researchers now know methods with which new plastics can be produced from 100 % recycled material, products that can even be used for food applications. This development is possible thanks to chemical recycling, through which polymer chains are first broken to then be reformed into new molecules, such as plastics but also other chemicals.

Polypropylene (PP) makes up a large share of our plastic waste. We investigated the conversion of PP over the industrial Fluid Catalytic Cracking catalyst (FCC‐cat) used to produce gasoline from crude oil fractions. We studied transport limitations arising from the larger size of polymers compared to the crude oil‐based feedstock by testing the components of this catalyst separately. Infrared spectroscopy and confocal fluorescence microscopy revealed the role of the FCC matrix in aromatization, and the zeolite Y domains in coking. An equilibrium catalyst (ECAT), discarded during FCC operation as waste, produced the same aromatics content as a fresh FCC‐cat, while coking decreased significantly, likely due to the reduced accessibility and activity of the zeolite domains and an enhanced cracking activity of the matrix due to metal deposits present in ECAT. This mechanistic understanding provides handles for further improving the catalyst composition towards higher aromatics selectivity., On the path to finding better catalysts for polyolefin plastic waste conversion to aromatics, we have found that a waste refinery catalyst performed better than the fresh catalyst with decreased accumulation of deactivating carbonaceous deposits. Fluorescence microscopy and vibrational spectroscopy has been used to elucidate the interaction of the polymer with the catalyst and to map the location and type of bulky aromatic species.

Windcatchers are built on the roofs of houses of hot areas of the Middle East to ameliorate the internal summer climate. The archaeological and historical record shows them to have been used since antiquity, and although they are still widely found in the region today, and regularly mentioned in the modern works on architecture o-f the region, no detailed study of their types or operation has been published. Rather architects refer continually to an accepted stereotype of their form and performance on which modern architects have to rely as a design model. This study makes an original contribution to the published record. In it the badgirs, or windcatchers of a single region, Yazd, on the Persian plateau, are described; and the distribution o-f their types in the villages of the area, and city of Yazd are reviewed in relation to the climatic and historical influences on their design and use. The functions o-F badgirs in the houses of Yazd, as airconditioners and ventilators, are investigated. General temperature limits o-F their summer performance in the context of the life-style of the Yazdi, are established and reviewed in relation to comfort and the physiology of the human body and the climatic results used to interpret the distribution of windcatchers types in the wider area of the Middle East. The research provides a unique historical record of the badgirs of Yazd, illuminates the complexity of the climatic and historical influences in their distribution, and, through analysis of their performance, provides a general climatic guide that may assist contemporary designers wishing to incorporate windcatchers in modern houses in hot areas.