The invention belongs to the technical field of development and application of
water treatment functional materials, and discloses a Fe3O4 / FeS composite modified
biochar material with good regeneration performance and preparation and application thereof, and the preparation method comprises the following steps: S1, material pretreatment, S2,
biochar preparation, and S3, FeS modified
biochar material preparation: sequentially adding FeSO4. 7H2O and biochar into a three-necked flask under the N2 protection condition, continuously stirring, carrying out suction
filtration, washing, and
drying to obtain the FeS modified biochar material. Slowly adding a Na2S solution, stirring at the rotating speed of 200rpm in the adding process, continuously stirring, and filtering, washing,
drying and sieving to obtain FeS-coated BC after the reaction is finished; and S4, preparing the Fe3O4 / FeS composite modified biochar material: sequentially adding FeCl3. 6H2O, FeSO4. 7H2O and
citric acid into a three-necked flask under the protection of N2, continuously stirring, slowly adding FeS (at) BC, uniformly stirring and mixing, carrying out constant-temperature water bath, dropwise adding NaOH to adjust the pH value to 10.5, carrying out secondary stirring, aging after the reaction is finished to obtain a black
composite material, washing, filtering, carrying out
vacuum drying, and sieving to obtain the Fe3O4 / FeS (at) BC. The method has the advantages and effects that the regeneration efficiency is high and stable, and the Mo (VI) adsorption efficiency is high.