PURPOSE: Sulfur compound is incorporated into iron-titanium-oxygen based catalyst, providing a NOX reducing catalyst having a high strength and resistant to SOX poisoning.
CONSTITUTION: An iron-titanium-oxygen based catalyst contains a sulfur compound in a composition ratio of Ti:0.6 to 48, Fe:5 to 61, S:5 to 15 in wt%, where iron sulfate is a preferable sulfur compound. For example, slurry of metatitanic acid in 1500 g (contains 18 wt% of Ti) is mixed with 1027 g of water-containing iron oxide (α-FeOOH) and 153 g of sulfuric acid, mixed for 2 hours at 80 to 90°C. and dried at 120°C for 10 hours. The resultant powder is added with 1 wt% of aqueous CMC solution to be blended, granuled and dried. After adding 0.2 wT% of stearic acid, the rotary tablet machine is used to make molded product, which is fired at 500° C for 3 hours, providing a catalyst having a composition of Ti:Fe:S=27:28:5.
SUGIMOTO TETSUYA
KAWAHARA SATOMI
YOSHIGATA KENJI
