Chlorpyrifos (CPF), a persistent organophosphorus insecticide, threatens soil health and food safety. Most studies focus on CPF adsorption in aqueous systems, while soil applications face challenges such as low adsorption efficiency, poor stability, and difficult recovery of adsorbents. To address these limitations, we synthesized low-cost β-cyclodextrin-magnetic sodium alginate composite-modified biochar (β-CD@MSA-BC) and compared its performance with crude BC (OBC) and β-CD-modified BC (β-CD-BC) for CPF adsorption in soil. The composite demonstrated enhanced thermal stability and a high BET surface area (77.45 m 2 /g) with a tailored pore structure. β-CD@MSA-BC achieved a CPF adsorption rate of 95.10% and a maximum adsorption capacity of 31.71 mg/g, significantly outperforming OBC (59.71%, 20.84 mg/g) and β-CD-BC (80.64%, 28.82 mg/g). Key mechanisms included hydrophobic inclusion, hydrogen bonding, π-π interactions, and Fe 3 ⁺ coordination. The material also demonstrated excellent pH adaptability, efficient magnetic recovery (> 90%), and maintained > 80% adsorption after three regeneration cycles. This work provides an efficient, recoverable, and soil-compatible adsorbent for sustainable remediation of CPF-contaminated soils.
Xie et al. (Mon,) studied this question.