Fabrication of Lead-based Metal-Organic Frameworks Using Recovered Lead for Solid-Phase Microextraction of p-Phenylenediamine Antioxidants.

The recycling of waste lead-acid batteries and the sensitive detection of trace p-phenylenediamine (PPD) antioxidants represent two pressing challenges in resource recovery and environmental safety. Herein, an integrated solution was proposed by synthesizing a novel lead-based metal-organic framework (WLP-Pb-MOF) from waste lead paste (WLP) as a sustainable metal source. The material served as a coating for a solid-phase microextraction (SPME) fiber. When coupled with gas chromatography-mass spectrometry, it enabled a highly sensitive method for determining three PPDs in water samples. The unique slit-shaped pore architecture and hydrophobic surface of WLP-Pb-MOF facilitated efficient enrichment through synergistic interactions, including size-sieving, hydrophobic partitioning, π-π stacking, and hydrogen bonding. This synergy resulted in extraction efficiencies significantly outperforming commercial SPME fibers. The method demonstrated good linearity from 5 to 2000 ng L-1, with detection limits of 0.29-1.60 ng L-1. In real water samples, the method achieved spiked recoveries of 91.3%-108.5%, with relative standard deviations below 8.78%. These results confirmed its accuracy and practical reliability. This work not only presents a viable strategy for the value-added recycling of waste lead but also provides a robust analytical platform for monitoring trace organic pollutants, effectively bridging sustainable resource recovery with advanced environmental monitoring.