Biochar/struvite composite as a novel potential material for slow release of N and P.
For soil and environmental remediation, biochar/struvite composites are prepared by the crystallization-adsorption method. The recovery rates of N, P, and Mg in the solution increase to 99.02%, 97.23%, and 95.22%, respectively, by forming 10% biochar/struvite composite. X-ray diffraction (XRD) patterns acquired from the 10% biochar/struvite composite show a crystalline structure of MgNH4PO4·6H2O (PDF no. 15-0762) and release of the main nutrient elements (N, P, Mg) from the 10% biochar/struvite composite increases significantly compared to struvite. The solubility of the biochar/struvite composite is the highest in 0.5 mol/L HCl, second in 20 g/L citric acid, and lowest in water. The power function equation describes more precisely the cumulative release of N, P, and Mg from the biochar/struvite composite in distilled water, whereas it follows the simple Elovich equation in 20 g/L critic acid and first-order kinetics equation in 0.5 mol/L HCl. Leaching experiments are performed on the biochar/struvite composite in soil, and the results indicate that the biochar/struvite composite has a longer cycle of release of nutrients than traditional chemical fertilizers and has large potential as a slow-release fertilizer.
['Hu|Pan|P|', 'Zhang|Yihe|Y|', 'Liu|Leipeng|L|', 'Wang|Xinke|X|', 'Luan|Xinglong|X|', 'Ma|Xi|X|', 'Chu|Paul K|PK|', 'Zhou|Jichao|J|', 'Zhao|Pengda|P|']
D000327:Adsorption D002606:Charcoal D052918:Environmental Restoration and Remediation D005308:Fertilizers D008956:Models, Chemical D009584:Nitrogen D010758:Phosphorus D012987:Soil D000069877:Struvite
Biochar/struvite composite Slow release Functionalized biochar Mineral fertilizer