A Sustained-Release Material for Removing Aniline from Groundwater Based on Waste Foamed Polystyrene as the Encapsulating Matrix

In this study, a novel slow-release material using recycled waste foamed polystyrene (WFPS) as the carrier was developed for the degradation of aniline-contaminated groundwater. Sodium persulfate (SPS) and zero-valent iron (ZVI) were embedded in WFPS, enabling the controlled and sustained release of reactive species. Systematic investigations were conducted to optimize the material’s composition and evaluate its performance under various conditions, including pH, initial aniline concentration, and the presence of common groundwater anions. The results revealed that the slow-release material effectively enhanced aniline degradation, achieving a maximum removal rate of 93.45% under flowing conditions. The degradation pathway was analyzed using GC-MS, identifying intermediates such as benzoquinone, hydroquinone, and dodecane, with eventual mineralization into CO2 and H2O. The material demonstrated robust performance, offering an efficient, cost-effective, and environmentally sustainable approach for in situ groundwater remediation.