Enhanced phosphate adsorption studies on several metal-modified aluminum sludge: preparation optimization, adsorption behavior, and mechanistic insight

• Published in: Environmental science and pollution research international 2023-04, Vol.30 (19), p.54628-54643
• Main Authors: Chen, Aixia, Guan, Juanjuan, Hu, Ruirui, Wei, Xiao, Zhang, Yixuan, Lv, Luxue, Wang, Xinyuan, Zhang, Lei, Ji, Luqian
• Format: Article
• Language: English
• Subjects: adsorbents; Adsorption; Aluminum; Aluminum - chemistry; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; coprecipitation; Earth and Environmental Science; Ecotoxicology; electrostatic interactions; Electrostatic properties; Environment; Environmental Chemistry; Environmental Health; Environmental science; Eutrophication; hydrogen; Hydrogen bonding; Hydroxyl groups; Kinetics; ligands; Metals; Optimization; Phosphate; Phosphates; phosphorus; Phosphorus - chemistry; Phosphorus removal; Research Article; Resource utilization; Sewage; Sludge; sorption isotherms; surface area; Surface chemistry; Waste Water Technology; Water Management; Water Pollutants, Chemical - analysis; Water Pollution Control; Zinc; Zirconium
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-023-26212-0

To solve the problems such as water eutrophication caused by excess phosphorus, the potential residual value of aluminum sludge was fully exploited and its phosphate adsorption capacity was further improved. In this study, twelve metal-modified aluminum sludge materials were prepared by co-precipitation method. Among them, Ce-WTR, La-WTR, Y-WTR, Zr-WTR, and Zn-WTR showed excellent adsorption capacity for phosphate. The adsorption performance of Ce-WTR on phosphate was twice that of the native sludge. The enhanced adsorption mechanism of metal modification on phosphate was investigated. The characterization results showed that the increase in specific surface area after metal modification was 9.64, 7.5, 7.29, 3, and 1.5 times, respectively. The adsorption of phosphate by WTR and Zn-WTR was in the accordance with Langmuir model, while the others were more following the Freundlich model ( R 2  > 0.991). The effects of dosage, pH, and anion on phosphate adsorption were investigated. The surface hydroxyl groups and metal (hydrogen) oxides played an important role in the adsorption process. The adsorption mechanism involves physical adsorption, electrostatic attraction, ligand exchange, and hydrogen bonding. This study provides new ideas for the resource utilization of aluminum sludge and theoretical support for preparing novel adsorbents for efficient phosphate removal. Graphical abstract