In the early decades of the nineteenth century scientist Sir Humphry Davy stumbled upon the phenomenon of heterogeneous catalytic oxidation when working on the development of the first-ever miner’s safety lamp. By inserting a platinum wire near the ignited wick of the lamp, Davy found it would catalyse the continued oxidation of coal gas.
This important discovery was the precursor to the use of platinum as an industrial catalyst in a process that has been around for over one hundred years – and which remains vital today; the production of nitric acid.
Nitric acid is a major feedstock for fertiliser and during its manufacturing process, oxidation of ammonia gas with air occurs to form nitric oxide. In order to achieve a high conversion efficiency, this is carried out at pressure over a platinum-rhodium catalyst.
Today, new applications for platinum catalysts continue to be found. Tanaka, the leading Japanese precious metals business, has recently won a Technology Award from the Catalyst Manufacturers Association, Japan, in recognition of its involvement in the development of a ‘hydrophobic’ platinum-based catalyst that prevents moisture build-up and enables a catalytic reaction to be maintained, even at ambient temperatures.