| 摘要 |
PURPOSE:To obtain a catalyst having high activity for denitration and low activity for oxidation of SO2 at relatively low temp. range by forming a ternary oxide of Ti, W, and Si previously, and adding a V compd. thereto. CONSTITUTION:In a process for prepg. a denitration catalyst by reducing nitrogen oxides contained in waste gas in the presence of ammonia, a ternary oxide of Ti, W, and Si is previously formed, and a V compd. is added thereto. For example, silica sol and an aq. soln. of water-soluble tungsten salt are added to metatitanic acid; the mixture is kneaded and dried by evaporating water, and then calcined at 150-650 deg.C. Aq. soln. of a V compd. is added to the obtd. powdery ternary oxide (TiO2.WO2.SiO2); the mixture is kneaded and heated to evaporate water to prepare extrudable paste, which is extruded into an appropriate mold. The molded product is dried and calcined at 150-650 deg.C in the air. The obtd. catalyst has high denitration activity and low oxidation activity for SO2 at relatively low temp. range of 200-450 deg.C. |
