Zinc(II) acetate Catalyzed Depolymerization of Poly(ethylene terephthalate)

Abstract

The depolymerization of plastic waste to valuable chemicals (waste‐to‐chemicals) can be a useful implement for a resource‐efficient economy. In this regard, the selective depolymerization of end‐of‐life poly(ethylene terephthalate) (PET) via zinc(II) acetate‐catalyzed methanolysis was investigated. As low molecular weight products dimethyl terephthalate and ethylene glycol were generated. With the support of microwave heating excellent yields and selectivities were realized and a selection of daily‐used PET goods were depolymerized. The obtained chemicals can be used for the (re)polymerization to new PET. Additionally, the generated dimethyl terephthalate was used as platform chemical for the synthesis of different molecules relevant for polymerization chemistry.

Expanding Plastics Recycling Technologies: Chemical Aspects, Technology Status and Challenges

“…Improved yields in this solvent mixture compared to pure methanol indicate that the rate of methanolysis strongly depends on PET solubility. Hofmann and coworkers 719 found that microwave irradiation facilitated the methanolysis of PET under even milder conditions using zinc acetate as a catalyst and CH2Cl2 as a cosolvent to improve solubility. In only 20 minutes at 160 °C, moderate to high yields of DMT were isolated from a variety of post-consumer PET sources, including a dish detergent bottle (46% yield), a soap dispenser with a label (70% yield), and a transparent food container (98% yield).…”

Recent advances in chemical recycling of polyethylene terephthalate waste into value added products for sustainable coating solutions – hopevs. hype

“…In another very recent study, Enthaler and co-workers reported depolymerization of end-oflife PET via zinc acetate-catalyzed methanolysis which produced a high dimethyl terephthalate yield of 98%. 87 However, the main drawback associated with methanolysis of PET is that, in addition to dimethyl terephthalate, the reaction products of methanolysis also contain glycols, alcohols, and phthalate derivatives. The separation and refinement of each product from others make methanolysis a rather costly process.…”

Degradasi Polietilen Tereftalat Dengan Radiasi Sinar Matahari Dan Metanolisis

“…Penelitian yang dilakukan melibatkan limbah PET yang diperoleh dari botol minuman bekas sebagai bahan dasar yang akan didaur ulang. Metode depolimerisasi yang digunakan adalah depolimerisasi secara kimiawi menggunakan pelarut benzil alkohol dengan katalis seng asetat sebagai garam logamnya (Hofmann et al, 2020) yang dimodifikasi dengan perlakuan awal berupa penjemuran botol bekas di bawah sinar matahari langsung dengan durasi waktu yang divariasikan sehingga akan diketahui pengaruh perlakuan tersebut terhadap proses degradasi PET. Karakterisasi dari hasil depolimerisasi tersebut diamati melalui perubahan titik leleh dan pengamatan gugus fungsi menggunakan FT-IR.…”

“…Degradasi PET secara metanolisisis (Hofmann et al, 2020) Sampel limbah PET ditimbang sebanyak 3 gram (g), kemudian dimasukkan ke dalam labu alas bulat 500 mL yang telah berisi 30 mL benzil alkohol dan katalis seng asetat yang divariasikan jumlahnya yaitu 0; 0,3; 0,6; dan 0,9 g untuk masing-masing sampel. Sampel direfluks selama 24 jam pada suhu 145-150 °C.…”