Using a natural chlorite as catalyst in chemical recycling of waste plastics: Hydrolytic depolymerization of poly-[bisphenol A carbonate] promoted by clinochlore. (1st February 2021)

• Record Type: Journal Article
• Authors: Quaranta, Eugenio; Mesto, Ernesto; Lacalamita, Maria; Malitesta, Cosimino; Mazzotta, Elisabetta; Scelsi, Enrico; Schingaro, Emanuela
• Is Part Of: Waste management. Volume 120(2021)
• Page Start: 642
• Page End: 649
• Publication Date: 2021-02-01
• Subjects: ATR Attenuated Total Reflectance -- BPA bisphenol A -- 4-CP 4-cumylphenol -- FTIR Fourier Transform Infrared -- GC gas-chromatography -- GPC gel permeation chromatography -- ICSD Inorganic Crystal Structure Database -- micro-XRF micro X-ray Fluorescence spectrophotometry -- MW microwave -- NMR Nuclear Magnetic Resonance -- PC poly-(bisphenol A carbonate) -- THF tetrahydrofuran -- T-O-T tetrahedral-octahedral-tetrahedral -- UR repeating unit -- XPS X-ray Photoelectron Spectroscopy -- XRPD X-ray Powder Diffraction; Chlorite -- Clinochlore -- Hydrolysis -- Plastics chemical recycling -- Poly-[bisphenol A carbonate] -- Waste valorization; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2020.10.031
• Languages: English
• ISSNs: 0956-053X

Abstract

Graphical abstract: Highlights: Clinochlore catalyzes the hydrolytic depolymerization of poly-[bisphenol A carbonate]. Bisphenol A formation is high yield (up to 98%) and selective (~99%) Exposed brucite-like sheets of chlorite take active part in promoting PC hydrolysis. Abstract: The present study describes the first example of utilization of a natural clay mineral as catalyst in a process addressed to chemical valorization of poly-[bisphenol A carbonate] (PC; (1 )) wastes. A natural clinochlore was investigated for the first time as the catalyst of the hydrolysis reaction of 1, a potential route to chemical recycling of wastes of this polymeric material. At 473 K, in tetrahydrofuran (THF) as the solvent, the mineral promoted effectively the depolymerization (up to 99%, after 6 h) of 1 by H2 O and the selective (~99%) regeneration of the monomer bisphenol A (BPA, (2 )). Temperature, catalyst loading, reaction time, H2 O/PC weight ratio affected markedly the productivity of the process. The role of the catalyst was also focused: the experimental data showed that the exposed brucite-like sheets of clinochlore are involved in the hydrolysis reaction and take active part in promoting the depolymerization process.