Simultaneous elimination of vanadium(V) and sulfamethoxazole from livestock wastewater with nitrogen-impregnated biochar

A cross-linked chitosan-modified birch sawdust biochar (CS@BSBC) was prepared and applied for the simultaneous elimination of vanadium (Ⅴ) and sulfamethoxazole (SMX) from livestock wastewater. The adsorption capacity of V(V) reached 110 mg/g alone while this value was promoted to 150 mg/g for the simultaneous removal of SMX and V(V), and the adsorption effect is optimal at pH 3. The adsorption capacity of SMX reached about 30 mg/g alone, while the SMX's adsorption capacity droped to 25 mg/g for the simultaneous removal of SMX and V(V). The mechanism studies disclosed that redox reactions occur on the surface of CS@BSBC. As revealed by the XPS spectra, 63 % of V(V) was reduced to V(IV) concurrently pyrolic nitrogen and C−O terminals were oxidized to nitrogen oxide and CO. The treatment mechanism of CS@BSBC described above can provide a reference for the subsequent treatment of livestock wastewater with complex composition and high vanadium content.