N-doped hollow spherical composite derived from coal gasification fine slag through spatial reconstruction for peroxymonosulfate activation

Using coal gasification fine slag (CGFS) as the raw material, the hollow spherical composite was successfully prepared by template-induced self-polymerization (TISP) method, achieving spatial separation and reconstruction of silicon-aluminum minerals and residual carbon. The composite featured enriched silicon-aluminum acid sites and the Fe-N structure with abundant carbon and nitrogen species, exhibiting excellent catalytic performance in the oxidation of phenol containing wastewater. The NCGFS-800/peroxymonosulfate (PMS) system could remove 99.7 % of bisphenol A (BPA) within 30 min, with a rate constant of 0.1932 min −1 and a mineralization efficiency of 78.4 %, which showed a good application potential in a wide pH range and coexistence of ionic. Specifically, the preparation process promoted the metal’s deconstruction and reorganization, formed more carbon defects in the structure, induced the formation of more high-value iron oxides in the system, and at the same time, pyridine nitrogen, graphitic nitrogen, and keto group (C=O) achieved ultrafast degradation effect by activating PMS to produce superoxide free radicals (O 2 – ·) and singlet oxygen ( 1 O 2 ). This work provides a feasible solution for the comprehensive utilization and high-value conversion of carbon ash from CGFS and provides a new idea for the design of efficient and stable porous nanoconfined.