Pedro Moura, Weiqing Zheng, Esun Selvam, Dionisios G Vlachos
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引用次数: 0
Abstract
Polyamides (PAs) are an important component of discarded textiles and food packaging. Chemical recycling can recover PA monomers, enabling repolymerization to produce virgin-grade PA. However, contemporary PA chemical recycling methods employ homogeneous catalysts that are hard to separate. Anatase TiO2 is reported as a catalyst for PA6 hydrolysis at 270 °C for 0.5 h, achieving a maximum ε-caprolactam (CL) yield of 81% (limited by thermodynamic equilibrium). The CL yield decreases upon catalyst reuse, due to loss of catalyst surface area induced by significant changes in catalyst crystallinity and texture. Pretreating the catalyst hydrothermally stabilizes it against morphological changes, yielding repeatable CL yields. Overall, this study discloses a heterogeneous catalyst capable of producing repeatable equilibrium CL yields via PA6 hydrolysis under industrially relevant reaction temperatures and times (<3 h, 250-330 °C).
期刊介绍:
ChemSusChem
Impact Factor (2016): 7.226
Scope:
Interdisciplinary journal
Focuses on research at the interface of chemistry and sustainability
Features the best research on sustainability and energy
Areas Covered:
Chemistry
Materials Science
Chemical Engineering
Biotechnology