Nano-Fe(0)/mesoporous carbon supported on biochar for activating peroxydisulfate to remove polycyclic aromatics hydrocarbons

The nano-Fe(0)/mesoporous carbon supported on biochar (MCFe/BC) was synthesized by a co-assembly process followed with carbon thermal reduction method. The specific surface area of MCFe/BC was 582.0 m2/g. The highest removal efficiency of pyrene in sand can reach about 40% after 7 h duration on MCFe6.2/BC with 6.2 wt% of iron by the peroxydisulfate advanced oxidation process (PDS-AOP). The removal efficiency of pyrene by adsorption at pH values varied from 4 to 10 in 24 h is around 40%, which shows that adsorption is independent with the pH values, while PDS-AOP is pH dependent, which is more efficient in acidic and basic conditions. The graphitic structure and oxygen-containing groups of carbon materials are benefit for adsorption of PAH. The presence of Nano-Fe(0) is responsible for the activation of peroxydisulfate especially at acidic condition. Our results indicate the potential of PDS-AOP using zero valent iron/porous biochar composite as the activator in practical soil remediation.