Bhattu Swapna, Madam Bobby Barnabas, Pragya Moni Gogoi, Pankaj Bharali, Giridhar Madras and Putla Sudarsanam
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引用次数: 0
Abstract
This study presents a decisive role of TiO2 morphology on the catalytic activity of MnOx/TiO2 nanomaterials for the chemical recycling of PET waste bottles using biomass-derived ethylene glycol to produce a valuable monomer, bis(2-hydroxyethyl) terephthalate (BHET). Three types of MnOx/TiO2 nanocatalysts were prepared by varying the TiO2 morphology (nanosheets: NS, nanotubes: NT, and nanorods: NR). The combination of MnOx nanoparticles and TiO2 nanorods (MnOx/TiO2-NR) showed significantly enhanced catalytic activity in PET glycolysis, with a 91% isolated yield of BHET at 190 °C in 3 h, whereas 74% and 82% yields of BHET were attained with MnOx/TiO2-NS and MnOx/TiO2-NT nanocatalysts, respectively. The morphology of TiO2 and the uniform dispersion of MnOx on TiO2-NR were confirmed by electron microscopic analysis. The MnOx/TiO2-NR catalyst contains optimum basic sites, which play a key role, along with surface hydroxyl species and Mn3+/Mn2+ species, in activating ethylene glycol and PET/its oligomers towards BHET formation. The excellent stability of the MnOx/TiO2-NR nanocatalyst, as confirmed by the hot-filtration test, good catalytic reusability up to four cycles, non-toxic nature, and the low cost of the MnOx/TiO2 materials indicate the practical feasibility of the developed catalytic protocol for the plastic recycling industry.
期刊介绍:
Nanoscale is a high-impact international journal, publishing high-quality research across nanoscience and nanotechnology. Nanoscale publishes a full mix of research articles on experimental and theoretical work, including reviews, communications, and full papers.Highly interdisciplinary, this journal appeals to scientists, researchers and professionals interested in nanoscience and nanotechnology, quantum materials and quantum technology, including the areas of physics, chemistry, biology, medicine, materials, energy/environment, information technology, detection science, healthcare and drug discovery, and electronics.