Degradation of thiocyanate by Fe/Cu/C microelectrolysis: Role of pre-magnetization and enhancement mechanism

Thiocyanate (SCN − ), a non-volatile inorganic pollutant, is commonly found in various types of industrial wastewater, which is resistant to hydrolysis and has the potential to be toxic to organisms. Premagnetized iron-copper-carbon ternary micro-electrolytic filler (pre-Fe/Cu/C) was prepared to degrade SCN − . Pre-Fe/Cu/C exhibited the most significant enhancement effect on SCN − removal when magnetized for 5 min with an intensity of 100 mT, and the SCN − removal rate was the highest at an initial pH of 3.0 and an aeration rate of 1.6 L/min. The electrochemical corrosion and electron transfer in the pre-Fe/Cu/C system were confirmed through SEM, XPS , FTIR , XRD , and electrochemical tests. This resulted in the formation of more corrosion products and multiple cycles of Fe 2+ /Fe 3+ and Cu 0 /Cu + /Cu 2+ . Additionally, density functional theory (DFT) calculations and electron paramagnetic resonance (EPR) were utilized to illustrate the oxygen adsorption properties of the materials and the participation of reactive oxygen species ( 1 O 2 , ·O 2 − , and ·OH) in SCN − removal. The degradation products of SCN − were identified as SO 4 2− , HCO 3 − , NH 4 + , and N 2 . This study introduced the use of permanent magnets for the first time to enhance Fe/Cu/C ternary micro-electrolytic fillers, offering a cost-effective, versatile, and stable approach that effectively effectively enhanced the degradation of SCN − .