| 摘要 |
<p>PURPOSE:To efficiently deposit and recover ammonium metavanadate of high purity by mixing a petroleum combustion ash with water, heating the mixture, adding ammonia thereto to specific pH, supplying an oxidizing agent thereto to separate an insoluble-component and cooling the liquid part. CONSTITUTION:The combustion ash captured by a dust collector, etc., provided in an exhaust gas flue of a boiler, etc., using petroleum fuel is mixed with the water to prepare a slurry. The slurry is heated to >=70 deg.C and the ammonia is added to the slurry to adjust the pH to 7-9. The oxidizing agent such as air is supplied to such slurry, while the temp. in the above-mentioned stage is maintained, the insoluble-component is separated and the liquid part is cooled down to <=40 deg.C to allow the ammonium metavanadate to deposit. The high- purity ammonium metavanadate is economically and efficiently recovered in such short stage.</p> |
