Electron transfer-driven polymerization of phenolics via CuO-catalyzed peracetic acid for sustainable wastewater...

Peracetic acid (PAA)-based advanced oxidation processes (AOPs) have shown promise for organic pollutants removal but predominantly rely on conventional mineralization pathways. Herein, we propose a novel strategy for eliminating phenolic contaminants via polymerization using a heterogeneous CuO/PAA system, in which phenolic compounds are not decomposed but primarily transformed into recoverable solid-state organic polymers. Mechanistic investigations reveal that the catalytic system leverages electron transfer from phenolic contaminants to activated PAA (e.g., CuO@PAA complex), generating phenoxy radicals that undergo crosslinking via polymerization and coupling reactions. Consequently, at neutral pH and low PAA dosage (3.0 mM), complete removal of diverse phenolic compounds (1.0 mM), including phenol, halophenols, cresol and bisphenols, was achieved within 90 min, with 60.5-74.9 % of total organic carbon (TOC) converted into solid-state polymers. More importantly, the electron transfer-driven polymerization maintained efficient in complex matrices and authentic coking wastewater, eliminating 100 % of volatile phenolics (1750 ± 25 mg/L) while generating recoverable polymers (150 mg/L) and enhancing biodegradability (BOD₅/COD from 0.22 to 0.52). Through the design of a dual-zone reactor, the CuO/PAA-driven polymerization process demonstrated scalability with reduced environmental impact. This work provides a sustainable paradigm for phenolic wastewater remediation via PAA-activated polymerization, enabling simultaneous contaminant elimination and carbon resource recovery.