In article , The Natural
Philosopher wrote:
We need platinum to make low emission cars.

Not really - same amount of emissions, different gases. The irony is
that the car produces more CO2 with the catalyst than without.

The catalyst reduces nitrous oxides to oxygen and CO2; Oxidises CO to
CO2 and oxidises any left over hydrocarbons to water and CO2.

--
David Biggins
Cambridge, UK