One-step valorization of cellulose acetate plastic waste into 5-hydroxymethylfurfural

Cellulose acetate (CA) is a versatile biopolymer derivative widely used in consumer products such as cigarette filters, textiles, and plastics. The extensive use of CA-based products generates substantial plastic waste, which can persist in the environment for over a decade due to its low biodegradability, posing serious environmental challenges. Herein, we report a one-step conversion process that transforms CA plastic waste into 5-hydroxymethylfurfural (HMF) while simultaneously recovering acetic acid. By employing AlCl 3 as a catalyst in an acetone-water solvent system at 160°C for 50 min, CA exhibited a 53.7 % HMF yield, a threefold increase compared to untreated cellulose, while also achieving a 97.3 % theoretical yield of acetic acid. The HMF yield exceeded 50 % when cigarette filters or CA fabrics were used as substrates. Molecular dynamics simulations revealed that the acetyl groups in CA enhance its coordination with acetone molecules, reducing the probability of protonation at the C1 and C4 oxygen atoms of the CA monomer and thereby suppressing the formation of undesired byproducts. Furthermore, the in-situ regenerated acetic acid actively promotes the HMF production. This study establishes a viable pathway for upcycling CA waste while advancing sustainable management strategies for CA-based plastics, offering a promising solution to mitigate environmental impacts.