iPDA-Assisted Design of Hierarchical Beta Zeolites for the Sustainable Upcycling of Polyethylene to Naphtha with Ultra-Low Pt Loading

The chemical upcycling of polyethylene (PE) into high-value naphtha is hindered by the inherent diffusion limitations of microporous zeolites and the destructive nature of conventional mesopore engineering. Herein, we utilize a transformative inner pore-directing agent (iPDA) strategy to fabricate hierarchical Beta zeolites that decouple mesopore formation from the loss of catalytic activity. By preadsorbing diethylamine (DEA) to shield intrinsic micropores during alkaline etching, we created a robust, interconnected mesoporous network (pore diameters >25 nm) while preserving critical Brønsted acid sites. When paired with an ultralow platinum loading (0.1 wt % Pt), this bifunctional catalyst achieves near-complete PE conversion (>99%) with an exceptional naphtha (C5–C12) selectivity exceeding 90% at 280 °C. This performance significantly outperforms conventional alkali-treated zeolites, which suffer from acidity depletion. Our findings demonstrate that strategic iPDA modification provides a scalable and efficient pathway for the precision design of catalysts capable of deconstructing macromolecular plastic waste into circular chemical feedstocks.