Resource utilization of copper slag for microelectrolysis material preparation for phenol degradation

Microelectrolysis (ME) is an efficient method for treating organic wastewater. The utilization of copper slag for high-performance microelectrolysis material preparation for pollutant degradation is meaningful for environmental conservation. Herein, a Fe-Cu-C microelectrolysis material (MEM) was prepared by carbothermal reduction with copper slag, copper powder and anthracite as the raw materials for phenol degradation in wastewater. The phase and structural transformations that occur in the reduction process of copper slag during MEM preparation were investigated via X-ray diffraction (XRD) and an electroprobe microanalyzer (EPMA). The prepared Fe-Cu-C MEMs were characterized by XRD, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The anchored structure of the iron droplets on the SiO2 bulk surface is beneficial for the microelectrolysis reaction as well as for the stability of the microstructure. The Fe-Cu-C MEM displayed wide pH and temperature application ranges for phenol degradation. Interestingly, 1O2 was found to play a critical role in phenol degradation in the ME system. Under the optimal conditions, the phenol degradation efficiency of Fe-Cu-C MEM reached 96.48% after 60 min, with chemical oxygen demand and total organic carbon removal rates of 82.65% and 67.34%, respectively. This research provides a feasible method for the production of Fe-Cu-C MEM and the degradation of phenol in wastewater.