| 摘要 |
PROBLEM TO BE SOLVED: To suppress the decomposition of a filter element, the degradation of properties and coloration by disposing a filter contg. composite particles which are formed by combining and integrating a granular semiconductor photocatalyst and granular amorphous calcium phosphate and a light source which emits light including a specific wavelength. SOLUTION: A weak alkaline ammonium triacrylate is added to a calcium hydroxide suspension under stirring obtain a soln. mixture. While the soln. is kept stirred by using a convection type high-speed stirring machine, an aq. phosphoric acid soln. is dropped to the soln. to adjust its pH. A soln. prepd. by dispersing titanium oxide under stirring by using the convection type high- speed stirring machine is added to ion exchange water to obtain a slurry 3. This slurry 3 is then supplied to an atomizer 6 of a spray dryer 5 by a fixed delivery pump 4 and is subjected to granulating and drying by a spray granulating and drying method, by which semiconductor photocatalyst composite particles 7 are obtd. The filter contg. such composite particles and the light source which emits the light including the wavelength 400 nm are disposed in the air purifying system. |
