摘要
SBC induces EPS restructuring via polysaccharide depletion and protein redistribution. • SBC-induced EPS restructuring accompanied a 9.33% decrease in non-freezable water. • DFT suggested water-associated stabilization at a simplified SBC-EPS interface. • Coupled EPS-hydration-electrochemical interactions enhance electro-dewatering efficiency. Interfacial water confined within extracellular polymeric substances (EPS) constitutes an important barrier to sludge dewatering, while EPS-associated water has generally been regarded as a retained phase rather than an active participant in interfacial restructuring. To address this gap, the potential state-dependent role of water at sludge-derived biochar (SBC)-EPS interfaces and the influence on electro-dewatering were investigated. The non-freezable water fraction derived by differential scanning calorimetry (DSC) decreased from 36.80% to 27.47%, while the sludge surface free energy based on extended DLVO (XDLVO) theory declined from 39.44 to 25.58 mJ/m 2 , suggesting reduced water confinement and weakened interfacial thermodynamics. Concomitantly, EPS restructuring was induced by SBC conditioning, accompanied by altered protein content, rearranged protein secondary structures, and polysaccharide depletion. Additional stabilization of protein-like EPS adsorption on the prehydrated SBC surface was indicated by the composition-balanced density functional theory (DFT), with the adsorption energy decreasing from −0.994 to −1.349 eV (ΔΔ E water = −0.355 eV). Moreover, the current response increased by 116.50%, and sludge cake moisture decreased from 64.46% to 41.78%. These findings support a possible hydration-related interfacial contribution associated with SBC-induced EPS restructuring, together with complementary structural and conductive contributions to electro-dewatering. Download: Download high-res image (150KB) Download: Download full-size image
危险品化学品经营许可证（带存储）