Work

Optimization of Biochar Adsorption Performance through Ball Milling and Nitrogen Doping: Mechanisms and Performance in Tetracycline Removal

Year: 2026

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide Antibiotic contamination in aquatic environments has become a critical environmental issue due to the persistence and ecological risks of tetracycline (TC). In this study, nitrogen-doped biochar (QN 7.5 BC) was synthesized via ammonia-assisted ball milling to serve as an efficient adsorbent. The process incorporated pyrrolic-N, graphitic-N, and pyridinic-N groups, enhancing the surface polarity and providing abundant active sites. QN 7.5 BC exhibited a high specific surface area of 206.88 m 2 /g and a total pore volume of 276 cm 3 /g. Batch adsorption experiments demonstrated a TC removal efficiency of 95.7%, which is more than twice that of pristine biochar. Spectroscopic analyses (FTIR, XPS, Raman) confirmed that nitrogen doping strengthened oxygen-containing functional groups (e.g., hydroxyl and carboxyl), promoted hydrogen bonding, π–π stacking, and electrostatic interactions, and improved structural stability, as reflected by a decrease in the Raman I D / I G ratio from 1.131 to 0.924. Even after TC adsorption, QN 7.5 BC maintained a good structural integrity. These findings highlight the synergistic effects of nitrogen doping and pore structure optimization in enhancing TC adsorption, thereby demonstrating the potential of QN 7.5 BC as a cost-effective and sustainable adsorbent for antibiotic wastewater treatment.

Source: ACS Omega

DOI: 10.1021/acsomega.5c07456