Catalytic oxidation of ammonia

In a method for the catalytic oxidation of ammonia comprising passing a mixture of ammonia and air over a catalyst under ammonia oxidation conditions, the improvement wherein said catalyst comprises:

• a composition of limited porosity, with a specific surface area between 0.02 and 2m.sup.2 /g, wherein said composition consists essentially of 0.1-10% of an active material selected from the group consisting of the metals of the platinum group, a refractory oxide carrier comprising, in the composition, 10-60% magnesia, 0.2 to 10% silica and 5-50% zirconia, and at least one metal oxide of the group consisting of oxides of iron, nickel, cobalt, titanium, vanadium, bismuth and molybdenum, all combined by mixing said active material, said refractory oxide carrier and said metal oxide in powdered form, compressing at 1,000-10,000 bars pressure and sintering at 1,300.degree.C or higher.

In a method for the catalytic oxidation of ammonia in a fluidized bed comprising introducing a mixture of ammonia and air into a fluidized bed of catalyst under ammonia oxidation conditions, the improvement wherein said catalyst comprises:

• a composition of limited porosity, with a specific surface area between 0.02 and 2m.sup.2 /g, wherein said composition consists essentially of 0.1-10% of an active material selected from the group consisting of the metals of the platinum group, and a refractory oxide carrier comprising in the composition, 10-60% magnesia, 0.2 to 10% silica and 5-50% zirconia, all combined by mixing said active material and said carrier in powdered form, compressing at 1,000-10,000 bars pressure and sintering at 1,300.degree.C. or higher.

In a method for the catalytic oxidation of ammonia in a fluidized bed comprising introducing a mixture of ammonia and air into a fluidized bed of catalyst under ammonia oxidation conditions, the improvement wherein said catalyst comprises:

• a composition of limited porosity, with a specific surface area sintering 0.02 and 2m.sup.2 /g, wherein said composition consists essentially of 0.1-10% of an active material selected from the group consisting of the metals of the platinum group, a refractory oxide carrier comprising, in the composition, 10-60% magnesia, 0.2 to 10% silica and 5-50% zirconia, and at least one metal oxide of the group consisting of oxides of iron, nickel, cobalt, titanium, vanadium, bismuth and molybdenum, all combined by mixing said active material, said refractory oxide carrier and said metal oxide in powdered form, compressing at 1,000-10,000 bars pressure and sntering at 1,300.degree.C or higher.