METHOD FOR PRODUCTION OF CATALYTIC SCREENS

摘要

Catalytic screens for ammonia combustion with air oxygen in reactors normally used for this purpose are produced by applying a thin layer of a catalytically active metal onto another, catalytically inactive support material. As the carrier of the catalytically active metal micro-expanded metal made of a suitable type of steel, preferably stainless steel with a high content of nickel, heat-resistant steel and the most preferably of Kanthal or Megapyr is used. To achieve optimum efficiency of ammonia oxidation more individual catalytic screens produced according to invention are put on each other. The catalytic layer consists of platinum, rhodium and palladium applied preferably with the cold dynamic spray method, which ensures the required adhesion of catalytically active metals to the micro-expanded metal and excellent surface resistance. The cold dynamic spray method also enables changing the portions of individual active metals in the layer. The arrangement of catalytic screens with different ratios of the applied metals serves the purpose of increasing the efficiency, reducing the emissions of undesired compounds and reducing losses of platinum in the course of using the catalyst.