Harvest of Cu NP anchored magnetic carbon materials from Fe/Cu preloaded biomass: their pyrolysis, characterization, and catalytic activity on aqueous reduction of 4-nitrophenol

Abstract

In the present study, a value-added Cu NP anchored magnetic carbon (Cu&Fe₃O₄-mC) material was obtained directly by fast pyrolysis of heavy metal polluted biomass (derived from a biosorption process using fir sawdust to remove Cu(II) from synthetic wastewater). The composition and structure of the Cu&Fe₃O₄-mC were characterized by various physicochemical techniques, which indicated that the Cu NPs were monodispersed on the mesoporous carbon support with an average particle size of 21.2 nm. The material shows favorable activity and separability on the catalytic reduction of 4-nitrophenol, and can be reused several times without a decrease in the catalytic activity. The maximum release concentration of Cu during the recycling process is 0.7 mg L⁻¹, which is below the limit of the Cu concentration in the surface water. This study would provide a green and sustainable pathway for simultaneous disposal of the biomass waste, removal of the heavy metal pollution, and pretreatment of 4-nitrophenol.