Abstract:In recent years, nitrate nitrogen pollution has gradually become an important water pollution problem that domestic and foreign scholars pay attention to. In order to remove the nitrate nitrogen in the water, the sawdust is modified by chemical methods to obtain an economical and efficient biomass adsorbent. The adsorbent was characterized by scanning electron microscopy (SEM), Fourier infrared spectroscopy (FT-IR), and Zeta potential (Zeta). This study mainly analyzed the influences of adsorbent dosage, adsorption time, pH, and initial concentration of nitrate-nitrogen on the removal of nitrate-nitrogen. The regeneration of the material was carried out research. The results show that the removal rate of modified sawdust for nitrate nitrogen stabilizes at 96±0.2% when the adsorbent addition is 10 g/L, the adsorption time is 20 min, the pH is 7, and the initial concentration of nitrate-nitrogen is 20-60 mg/L, and the removal rate of nitrate nitrogen by modified sawdust after regeneration can reach 95%. The adsorption process conforms to the Freundlich isotherm model. It is concluded that the modified sawdust has a good ability to remove nitrate-nitrogen in wastewater.