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In order to enhance the removal performance of graphitic carbon nitride (g-C3N4) on organic pollutant,a simultaneous process of adsorption and photocatalysis was achieved via the compounding of biochar and g-C3N4.In this study,g-C3N4 was obtained by a condensation reaction of melamine at 550℃.Then the g-C3N4/biochar composites were synthesized by ball milling biochar and g-C3N4 together,which was considered as a simple,economical,and green strategy.The characterization of resulting g-C3N4/biochar suggested that biochar and g-C3N4 achieved effective linkage.The adsorption and photocatalytic performance of the composites were evaluated with enrofloxacin (EFA) as a model pollutant.The result showed that all the g-C3N4/biochar composites displayed higher adsorption and photocatalytic performance to EFA than that of pure g-C3N4.The 50% g-C3N4/biochar performed best and removed 45.2% and 81.1% of EFA (10 mg/L) under darkness and light with a dosage of 1 mg/mL,while g-C3N4 were 19.0% and 27.3%,respectively.Besides,50% g-C3N4/biochar showed the highest total organic carbon (TOC) removal efficiency (65.9%).Radical trapping experiments suggested that superoxide radical (·O2-) and hole (h+) were the main active species in the photocatalytic process.After 4 cycles,the composite still exhibited activity for catalytic removal of EFA.