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An efficient oxidation degradation is achieved together with full recovery of the degradation product via the selective cleavage of the C–C and C–O bonds in the hydroxyethyl ether unit, and the C–N bonds using the ammonium ceric nitrate system.

The high mechanical strength and thermal resistance of an epoxy (EP) thermoset make it ideal for wide applications in industries such as energy, aerospace, electronics, and construction but increase the difficulty in controllable and efficient recovery. Herein, acidic ion exchange resin-induced oxidative degradation of the EP thermoset was developed to obtain homogeneous oligomers at 85 °C in 4 h. The C–N bond is activated by free H+ of the ion exchange resin while the oxidation depth was dependent of acid groups of the ion exchange resin. There was no significant difference in the molecular weight or polydispersity index after complete degradation even when varying the degradation temperature and time. Even more, homogeneous degraded EP microspheres can be easily obtained by a water-induced phase separation method and it was a good candidate for wastewater treatment in the field of dye removal with a CV adsorption capacity of 270 mg/g and oil–water separation with a water flux of 57,325 L m–2 h–1 and a separation efficiency of 99.9%. This work overcomes the shortcomings of non-controllable degradation and the resultant complex products in traditional oxidative degradation systems of the EP thermoset. In addition, it provides a new insight into controllable recovery and value-added reutilization by taking advantages of both the waste EP and waste acidic ion exchange resins.

Biodegradable plastics are considered one of the solutions to solve the environmental pollution caused by plastic waste. However, on easy-to-collect occasions, recovery of biodegradable plastics is a preferable option rather than biodegradation, since it can fully utilize carbon resources and reduce carbon emissions. Herein, efficient and eco-friendly recycling of widely used biodegradable plastic, polybutylene adipate terephthalate (PBAT), was demonstrated by alkaline hydrolysis in the solution of ethanol and H 2 O. The degradation ratio of PBAT was achieved above 99% at 80 °C for 50 min. Diacid salts were self-precipitated out from the reaction solution, followed by acidification to obtain diacid monomers. The reaction solution after filtrating away the diacid salts can be recycled several times without sacrificing the degradation ratio of PBAT, while 1,4-butanediol monomer can be further recovered by the two-step mild distillation at 80 °C. The carbon emission of the whole recycling process was evaluated, and it was only half of that of the biodegradation. The work provides new insight into the recycling of biodegradable plastics.

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