| 摘要 |
A process for decreasing the content of nitrogen oxides in flue gases. The process comprising contacting the flue gases with a catalyst. The catalyst contains at least one of the metals titanium, zirconium, vanadium, tungsten, molybdenum, or cerium in the form of one or more of their oxides combined with a silicate with a layer structure (layer silicate) comprising acid-activated kaolin. The crystalline layer structure of the acid-activated kaolin is essentially retained, while being not yet X-ray amorphous. The acid activation increases the BET surface area at least 15% and preferably at least 50% in terms of the BET surface area of the kaolin before acid activation. The atomic ratio of the silicon in the acid-activated kaolin to the metal in the oxide is from 0.2 and 50 and preferably from 0.4 to 25. |
