Catalyst in the preparation of nitric acid|
Platinum is mainly used in the free metal form, as catalyst in hydrogenation reactions performed in organic chemistry. It is also used in the preparation of gasoline to increase its yield and in the purification of gases for catalytic oxidation. Metallic screens made of platinum-rhodium can be used to catalyze the ammonia oxidation in nitric oxide to prepare nitric acid. Pure platinum is used, in resistive thermometers and in thermo-couples, with a platinum-rhodium alloy. This alloy is used during the process of producting artificial silk and glass fibers. The alloy of platinum-iridium is used in jewelry, laboratory utensils, electrodes and electric contacts. Alloyed with palladium, platinum is used in dental prosthesis.