Purification catalyst for interior of polymer film production furnace and purification method for interior of polymer film production furnace

Abstract

A high durability catalyst for decomposing volatile organic compounds (VOCs) or sublimable organic substances, generated inside a polymer film production furnace, at a high conversion rate is provided. A method for purifying a gas inside a polymer film production furnace with the use of the catalyst is also provided. Provided are a purification catalyst for a gas inside a polymer film production furnace, which contains a mixed oxide composed of a manganese-based oxide containing manganese and potassium and having a cryptomelane structure, and copper oxide; and a method for purifying a gas inside a polymer film production furnace, comprising a step 1 of bringing hot air containing volatile and/or sublimable organic substances, generated during production of a polymer film by the polymer film production furnace, into contact with the catalyst provided inside or outside the furnace, at a temperature in the range of 200 to 350° C. to decompose the organic substances oxidatively, and a step 2 of refluxing all or a part of a resultant decomposition gas to the polymer film production furnace.

1 . A purification catalyst for a gas inside a polymer film production furnace,
 the purification catalyst containing a mixed oxide composed of   a manganese-based oxide containing manganese and potassium and having a cryptomelane structure, and   copper oxide.   
     
     
         2 . The purification catalyst according to  claim 1 , wherein a content of the copper oxide is 10 to 30% by weight as CuO based on the mixed oxide. 
     
     
         3 . The purification catalyst according to  claim 1  or  2 , wherein a content of the manganese is 65 to 85% by weight as MnO 2  based on the mixed oxide. 
     
     
         4 . The purification catalyst according to  claim 1 , wherein a content of the potassium is 0.1 to 10% by weight based on the mixed oxide. 
     
     
         5 . The purification catalyst according to  claim 1 , wherein a specific surface area (BET specific surface area) of the mixed oxide is 200 m 2 /g or more. 
     
     
         6 . The purification catalyst according to  claim 1 , wherein a specific surface area (BET specific surface area) of the mixed oxide after being heated for 1 hour at 500° C. is 85 m 2 /g or more. 
     
     
         7 . The purification catalyst according to  claim 1 , wherein the gas inside the polymer film production furnace contains volatile and/or sublimable organic substances generated during production of a polymer film. 
     
     
         8 . The purification catalyst according to  claim 1  supported on a catalyst support medium. 
     
     
         9 . A method for purifying a gas inside a polymer film production furnace, comprising:
 a step 1 of bringing hot air containing volatile and/or sublimable organic substances, generated during production of a polymer film by the polymer film production furnace, into contact with the catalyst according to  claim 1 , which is provided inside or outside the furnace, at a temperature in a range of 180 to 350° C. to decompose the organic substances oxidatively; and   a step 2 of refluxing all of or a part of a resultant decomposition gas to the polymer film production furnace.