| 摘要 |
A method for continuously preparing a metal oxides catalyst comprises the following steps: dissolving metal materials using nitric acid solution to produce a metal nitrate solution, and also to produce NOx and water vapor; hydrolyzing the metal nitrate solution by introducing pressurized superheated water vapor into the metal nitrate solution to obtain a slurry of the hydrates of metal oxides as well as acidic gas, the main components of the acidic gas are NO2, NO, O2 and water vapor; filtrating and drying the slurry to obtain the hydrates of metal oxides and/or metal oxides; and then utilizing the obtained hydrates of metal oxides and/or metal oxides as raw materials and preparing the metal oxides catalyst by the conventional method for preparing a catalyst. The NOx gas produced can be absorbed to produce nitric acid which can be reused. An apparatus used for preparing metal oxides comprises a metal salt solution preparation system, a metal salt solution hydrolysis system, a product preparation system and a nitric acid preparation and recycling use system. The method and the apparatus can achieve continuous production, enclosed circulation and zero release in the whole process and can reduce the cost of production. |
