Acrylonitrile–butadiene–styrene (ABS) plastics, commonly found in electronics, automotive parts, and household items, continue to pose a substantial environmental challenge, with the majority still ending up in landfills or incinerators. Dissolution-based recycling methods have emerged as effective alternatives to conventional mechanical recycling, particularly for recovering high-quality fractions. This work explores the use of eutectic solvents (ESs) as renewable, low-impact alternatives for the selective dissolution and recovery of ABS components—specifically, the styrene–acrylonitrile (SAN) copolymer. A computational solvent screening of over 30,000 potential candidates was conducted using the Conductor-like Screening Model for Realistic Solvents (COSMO-RS), followed by experimental validation to assess the solubility of SAN in selected ESs. The solubility of SAN was assessed under mild conditions (60 °C, 1 h), and three ES systems were found to be effective, with recovery yields up to 70%. The recycled polymer and residues were characterized using Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) analyses. Notably, preliminary results suggest that effective dissolution is possible even at ambient temperature and pressure. These findings highlight the potential of ESs as sustainable and scalable solutions for the recovery of difficult-to-recycle polymeric waste such as ABS.
Author Contributions
V.d.P. contributed to the investigation, practical experimentation, data curation, validation, and writing—original draft, as well as writing—review and editing. P.S.S.L. contributed to practical experimentation, data curation, formal analysis, and writing— reviewing and editing. L.C. contributed to practical experimentation, data curation, formal analysis. F.H.B.S. contributed to the practical experimenting, data curation, formal analysis, as well as writing—review and editing. A.M.F. contributed to project conceptualization, supervision, validation, writing—original draft and writing—review and editing. A.F.S. contributed to project conceptualization, funding acquisition, supervision, validation, writing—original draft and writing—review and editing. All authors have read and agreed to the published version of the manuscript.
Funding
This work was developed within the scope of the project CICECO–Aveiro Institute of Materials, UID/50011 & LA/P/0006/2020 (DOI 10.54499/LA/P/0006/2020), financed by national funds through the FCT/MCTES (PIDDAC). The NMR spectrometers are part of the National NMR Network (PTNMR) and are partially supported by Infrastructure Project Nº 022161 (co-financed by FEDER through COMPETE 2020, POCI and PORL and FCT through PIDDAC). This research is also sponsored by FEDER funds through the program COMPETE—Programa Operacional Factores de Competitividade—and by national funds through the FCT under the project UID/EMS/00285/2020. A.M.F., F.H.B.S., and A.F.S. acknowledge FCT for the research contracts CEECIND/00361/2022, CEECIND/07209/2022, and CEECIND/02322/2020 under the Scientific Stimulus—Individual Call, respectively. V.P. and L.C. acknowledge the European Commission for the research grant under Horizon Europe ABSolEU—“Paving the way for an ABS recycling revOLution in the EU” (HORIZON-CL4-2021-RESILIENCE-01-Project: 101058636) HOP ON program.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
The data presented in this study are available on request from the corresponding author due to intellectual property and confidentiality agreements governing a Horizon Europe–funded European research consortium.
Conflicts of Interest
The authors declare no conflicts of interest.
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