Calculated Physicochemical Properties of Glycerol-Derived Solvents to Drive Plastic Waste Recycling

Abstract

Plastic waste has become a major environmental crisis, with the majority of plastic being produced ending up in open landfills and waterways every year. Solvent-based recycling approaches offer an effective means of recovering high-quality plastic materials from waste by the use of a solvent to selectively dissolve the plastic waste and recover specific polymers. In this work, we report on the properties of 9587 potential glycerol-based solvents that can be synthesized from biomass-derived glycerol. We predict the density and dipole moment using quantum mechanical calculations, while LogS, LogP, and melting point are predicted using machine learning that outperforms other prediction methods such as Hansen Solubility Parameters in Practice (HSPiP). Additionally, we analyze the ability of the solvents to dissolve common plastic materials [polyethylene (PE), poly(ethylene terephthalate) (PET), poly(ether sulfone) (PES), polypropylene (PP), polystyrene (PS), and poly(vinyl chloride) (PVC)] based on a comparison of their Hansen solubility parameters (HSPs). Our results show that functionalization of glycerol can significantly alter its properties, and based on the HSPs and melting point, we recommend selective solvents for PE, PET, and PVC, while for PES, PP, and PS, we suggest using a combination of solvents in a solvent/antisolvent setup for solvent-based plastic waste recycling. Finally, based on stricter solvent selection criteria, we also propose a strategy that may help reduce the costs of sorting waste plastic whereby the waste feedstock is first separated into polar and nonpolar fractions.

Characterizing Polyvinyl Chloride Interactions with Additives in Traditional and Bioderived Solvents

“…(b) Molecular structures of traditional and bioderived solvents. RED: relative energy difference describing the compatibility between PVC and solvent based on their solubility parameters, obtained from literature. , …”

“…We further examined the mixing thermodynamics and stress–strain profiles of PVC in both traditional and bioderived solvents (S10, S11, S12, S13 and S14) taken from studies by Soyemi et al and Chatterjee et al The system compositions at solvent mass concentrations of 10%, 50%, and 80% are detailed in Table .…”

“…The shift toward increased sustainability has highlighted the need for improved bioderived solvents for polymer processing. ,− Recently, Soyemi and Szilvási computationally screened a large library of 9587 different glycerol-based molecules as potential bioderived solvents for plastic waste upcycling (some of which have been experimentally synthesized). Biomass-derived glycerol is produced in large volumes as a side product of biodiesel production, and it is often treated as a waste, so there is a strong need to retain this carbon resource.…”

“…In this work, bioderived solvents having a wide range of RED values are investigated (to broadly sample the range of chemical structures studied in literature , ). Through detailed MD simulations, we predict the influence of these solvents on the structural and thermomechanical stability of PVC, comparing their effectiveness to traditional PVC solvents such as tetrahydrofuran (THF), which serve as performance benchmarks.…”

Heterogeneous Catalytic Peroxide Oxidation Inducing Surface Reactions Toward Flotation Extraction of Hazardous Poly(Vinyl Chloride) From Waste Plastics

“…Currently, global plastic production is 320 million metric tonnes and will double soon. , To date, 80% of produced plastics have been buried in the ground or abandoned in environments. Notably, the resulting recalcitrant plastics with sizes of less than 5 mm threaten surrounding environments and biohealth. ,, The proposition of physical recycling is recognized in plastic remediation, but the heterogeneity of plastics hampers recycling via deteriorating properties of recycled products due to the differentiated physical and chemical properties. − Therefore, separation is significant for plastic recycling. PVC, as the single largest chlorine source, has a higher separation priority than other plastics because ubiquitous chlorines can jeopardize recycling processes and environment safety by producing dioxins and dioxin-like compounds. , …”