Microwave-intensified catalytic upcycling of plastic waste into hydrogen and carbon nanotubes over self-dispersing bimetallic catalysts

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 483; p. 149270
• Main Authors: Zhao, Jun, Gao, Jianye, Wang, Duanda, Chen, Yong, Zhang, Lei, Ma, Wangjing, Zhao, Sui
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2024
• Subjects: Carbon nanotubes; Hydrogen; Metal catalysts; Microwave; Plastic waste; Microwave; Carbon nanotubes; Hydrogen; Metal catalysts; Plastic waste
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.149270

[Display omitted] •Several self-dispersing catalysts with advanced catalytic activity are constructed by a simple one-step method.•Microwave-intensified catalytic upcycling of plastic into hydrogen and carbon nanotubes is discussed.•The mechanism of plastic catalytic upcycling transformation is investigated.•Well-dispersed polymetallic catalysts improved the dehydrogenation and synergistic catalysis efficiency. The value-added utilization of plastic waste is a powerful way to effectively manage plastic waste and achieve a circular economy. However, high-performance catalysis often requires suitable substrate catalysts or complex processes, while low-energy consumption plastic upcycling technology is also urgently needed. In this study, various cheap and self-dispersing highly active iron-cobalt–nickel-monometallic and bimetallic functional catalysts were synthesized through a simple and fast one-step method for catalytic upcycling of plastic into hydrogen and carbon nanotubes. Results indicated that Ni1Fe3Ox, Ni1Co3Ox and Ni3Co2Ox are the most efficient catalysts, realizing hydrogen yield as high as 60.2 mmol g-1 plastic, 63.2 mmol g-1 plastic, 63.5 mmol g-1 plastic and high selectivity of 79.4 vol%, 81.4 vol% and 83.7 vol%, respectively, for microwave-intensified catalytic dehydrogenation of LDPE, the hydrogen yield of which is almost 2–3 times that of traditional thermal catalysis. More importantly, a high hydrogen yield of 44.1 mmol g-1 plastic is also achieved when the feedstock is extended to the landfill mixed plastics waste. These results demonstrate that the synergies of self-dispersing bimetallic catalysts are promising for plastic waste upcycled via microwave-intensified catalysis.