Currently, the most widely used SCR denitration catalyst is the vanadium pentoxide-tungsten trioxide-titanium dioxide base monolithic denitration catalyst, wherein the carrier is titanium oxide; the main active component is vanadium pentoxide; tungsten trioxide plays the roles of enhancing the acidity, expanding SCR denitration reaction temperature window, inhibiting anatase transfer into rutile, reducing the conversion of sulfur dioxide to sulfur trioxide, improving the ability of anti-poisoning of the catalyst.

 

In this paper, we will introduce the preparation of tungsten trioxide denitration catalyst which is taking titanium dioxide- aluminosilicate fiber paper as the composite carrier. The preparation steps are like bellows:

1. Select the silica-alumina fiber paper, industrial grade anatase type titanium oxide as raw material, the titanium dioxide slurry is first prepared (wherein 30% ammonia stabilized silica sol is added), then form to a cylindrical;

2. Dried at 100°C for 1 hour and calcined segment (respectively insulate at 100°C, 200 °C, 300°C, 500°C for 1 hour), to obtain a catalyst carrier;

3. Preparing the tungsten trioxide denitration catalyst by wet impregnation method, wherein the mass fractions of ammonium metavanadate, ammonium tungstate, ammonium molybdate are respectively 1% to 5%, 5% to 15% and 0% to 5%;

4. Drying the catalyst at 100°C for 1 hour and then segment calcined (respectively insulate at 100°C, 200 °C, 300°C, 500°C for 1 hour) to obtain tungsten trioxide SCR denitration catalyst.

 

Experiments have shown that the SCR denitration catalyst which takes titanium dioxide-aluminosilicate fiber paper as the composite carrier, the carrier and catalyst itself can maintain good porous structure in the condition of calcined at 500°C, while anatase titanium dioxide do not rutile; In addition, when the contents of active component-vanadium pentoxide, tungsten trioxide, molybdenum trioxide are respectively 3%, 7%, 4%, the denitration efficiency is up to 92%.