Pan Hu1,2, Yihe Zhang3, Leipeng Liu2, Xinke Wang2, Xinglong Luan2, Xi Ma4, Paul K Chu5, Jichao Zhou6, Pengda Zhao7. 1. School of Earth Sciences and Resources, China University of Geosciences, Beijing, 100083, People's Republic of China. 2. Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing, 100083, People's Republic of China. 3. Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing, 100083, People's Republic of China. zyh@cugb.edu.cn. 4. State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing, 100029, People's Republic of China. 5. Department of Physics and Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China. 6. Hunan University of Arts and Science, Changde, 415000, People's Republic of China. 7. School of Earth Sciences and Resources, China University of Geosciences, Beijing, 100083, People's Republic of China. pdzhao@cugb.edu.cn.
Abstract
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.
For soil and environmental remediation, biochar/struvite composites are prepared by the crystallization-adsorption method. The recovery rates of N, P, and n>an class="Chemical">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.
Entities:
Keywords:
Biochar/struvite composite; Functionalized biochar; Mineral fertilizer; Slow release
Authors: Ying Yao; Bin Gao; Mandu Inyang; Andrew R Zimmerman; Xinde Cao; Pratap Pullammanappallil; Liuyan Yang Journal: J Hazard Mater Date: 2011-03-29 Impact factor: 10.588