Abstract: The invention concerns particles which may include a catalytically active component, in the form of a three-dimensional ellipsoidal shape having three major axes at least two of which axes are of different lengths. Beds of such particles are useful for forming particle beds through which a fluid may flow.

Abstract: The invention concerns particles which may include a catalytically active component, in the form of a three-dimensional ellipsoidal shape having three major axes at least two of which axes are of different lengths. Beds of such particles are useful for forming particle beds through which a fluid may flow.

Abstract: A catalyst charge for ammonia oxidation, including the Andrussow process, comprises a first stage ammonia oxidation catalyst capable of oxidising 20 to 99% of designed ammonia throughput, to produce a first stage product gas comprising unreacted ammonia, oxygen and nitrogen oxides, and a second stage ammonia oxidation catalyst capable of completing the oxidation of unreacted ammonia. Low levels of nitrous oxide are produced an extended campaign lengths may be seen.

Abstract: An iridium alloy consists essentially of iridium and at least one of W and Zr, and optionally Rh. When present, W comprises between 0.01 and 5 wt % of the alloy; when present in combination with W, Zr comprises between 0.01 and 0.5 wt % of the alloy; when present alone or in combination with Rh only, Zr comprises between 0.01 and 0.09 wt % of the alloy; and when present, Rh comprises between 0.1 and 5 wt % of the alloy. The alloys may be modified by the addition of platinum and other platinum group metals and base metals. The alloys demonstrate enhanced physical and chemical properties and are suitable for use as electrode materials in spark plugs and other high temperature applications.