Work

Preparation of plane trees’ bark biochar/ZnAl-LDH and its adsorption performance for phosphate and recovery

Year: 2025

Type: article

Abstract: Biochar is an excellent adsorbent for organic pollutants, but the removal effect for inorganic phosphorus is not satisfactory. In order to improve its phosphorus removal effect, ZnAl-LDH modified plane trees’ bark biochar was presented in this paper. The plane trees’ bark biochar was prepared by chemical-activation method by utilizing K 2 CO 3 as the activation agent. And then, ZnAl-LDH modified biochar was prepared by in-situ co-precipitation method with ammonia as the precipitate agent. As the sample was as little as 10 mg, the adsorption ratio was about 93% for the 25 mL of 20 mg/L PO 4 3− . The saturated adsorption capacity for PO 4 3− was 103.1 mg/g, calculated by Langmuir equation, revealing the adsorption was mainly mono-molecular layer adsorption. The possible adsorption mechanism of phosphate mainly contained interlayer anion exchange, surface complexion and ligand exchange. Moreover, the absorbed sample were soaked in 5.5% Na 2 CO 3 solution for phosphate desorption, nearly 60% of the absorbed phosphate could be recovered and may reuse in the future.

Source: Scientific Reports

DOI: 10.1038/s41598-025-16876-8