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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Das Vergrößern des Recyclingstroms erfordert einen neuen Ansatz, der über das Schmelzen und Umformen hinausgeht. Es gibt einige Techniken des chemischen Recyclings mit dem Potential, bestehende Recyclingmöglichkeiten zu ergänzen. In diesem Aufsatz sind die Methoden des chemischen Recyclings dargestellt und anhand einer Ökobilanz bewertet, ergänzt durch eine Aufzählung von Prozessen und Firmen in diesem Bereich. Wir zeigen, dass bestimmte Techniken besonders für spezifische Müllströme geeignet sind und dass nur eine Kombination aus den vorhandenen Methoden geeignet ist, das Kunststoffmüllproblem zu lösen. Aktuelle Forschung sollte realistischeren und weniger reinen Mischströmen größere Aufmerksamkeit widmen, während Trenn‐ und Sortierprozesse z. B. durch effektivere Regularien verbessert werden müssen. Dieser Aufsatz soll zur Entwicklung von Verfahren inspirieren, mit denen hochwertige Produkte hergestellt werden können, die die Kreislaufwirtschaft antreiben, indem sie nötige Wirtschaftsanreize und Erleichterungen für die Umwelt bieten. [ABSTRACT FROM AUTHOR]

Background There has been a dramatic increase in autism around the world. However, little is known about the impact of the Taiwanese primogeniture system on mothers of children with ASD. Greater knowledge is needed to understand the life experiences of Taiwanese mothers with ASD children when a healthy male descendent is expected. Materials and Methods Research follows the hermeneutic phenomenological approach with in-depth interviews and participant observation (Agar, Speaking of Ethnography. Sage, California, 1986). The researchers collected and analysed stories from seven mothers who are the major caregivers of their school-aged autistic children. Results The data revealed the following themes that represented the mothers' experiences: taking the blame, my world was turned upside down, a child-centred life and two lives as one. Conclusions The findings provide a deeper understanding of common expectations of, and behaviours directed towards, Taiwanese mothers of children with autism. This offers healthcare professionals ways of reconceptualizing therapeutic practice, thus benefitting these mothers. [ABSTRACT FROM AUTHOR]