During the process of extracting vanadium from vanadium slag by sodium roasting-water leaching method, silicon in the leaching solution will react with alkali to form sodium silicate and enter the solution, affecting the recovery rate and quality of the product. To address this issue, the selective precipitation of silicon in vanadium leachate by the magnesium salt method was studied. Thermodynamic equilibrium diagrams of the Mg-Si-V-H2O system were constructed to investigate the distribution characteristics of free ions within the pH range of 7~14. Additionally, the relationship between pH and precipitation saturation indices was established to evaluate the precipitation behaviors of MgSiO3 and Mg(VO3)2 under different pH conditions. The calculation results reveal that the solubility of MgSiO3 is relatively low, while that of Mg(VO3)2 is relatively high, which can achieve the selective precipitation of silicon in the vanadium leaching solution. The verification test results demonstrate that the pH of the solution has a significant influence on the precipitation rate of silicon in the vanadium leaching solution. When pH=10, the silicon precipitation rate can reache 86.3%, and the vanadium loss rate is only 3.2%, with a good effect.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |