Upcycling Polybutylene Succinate Waste to Succinic Acid via Paired Electrocatalytic using Thiol‐Engineered MOFs and a CO ₂ ‐Assisted Precipitation System

Abstract While electrocatalytic conversion of biodegradable Polybutylene succinate (PBS) plastic‐derived 1,4‐butanediol (BDO) into succinic acid (SA) offers an eco‐friendly recycling solution, current technologies face key limitations: lack of efficient catalysts, low Faradaic efficiencies (FE), and costly membrane/separations. These challenges hinder the practical implementation of this promising plastic‐to‐value chemical approach. Herein, a paired electrocatalytic strategy is reported for converting PBS waste into SA using thiol‐engineered Metal‐organic frameworks coupled with CO 2 ‐assisted precipitation. Specifically, a heterogeneous electrocatalyst where NiS clusters embedded in NiBDC nanosheets (NiBDC@NiS 0.68 ) is synthesized, achieving remarkable performance with 95.7% FE and 92.5% yield during BDO‐to‐SA conversion. Combined in situ techniques and theoretical calculations indicate that tailored local chemical heterogeneity within the catalyst enhances alcohol affinity, facilitates electron transfer, and optimizes reactant/intermediate adsorption. Additionally, a membrane‐free co‐electrolysis system is engineered to simultaneously oxidize PBS waste at the anode and reduce maleic acid at the cathode, yielding an unprecedented overall 183.8% FE for SA production. The integrated process concludes with CO 2 ‐assisted precipitation, yielding high‐purity SA while coproducing valuable NaHCO 3 . This work demonstrates that precise local environment modulation in catalyst design, combined with deliberate system integration, can enable sustainable plastic upcycling, delivering both environmental and economic benefits by efficiently converting PBS waste into valuable SA.