The evolution of catalytic converters

Smog problem

As early as the 1940s and 50s, air quality in many of the major cities in the world had deteriorated to such an extent that a solution needed to be found. A major contributor to this pollution was photochemical smog and low-level ozone caused by the pollutants emitted from motor vehicles. 

To combat this problem, in the mid-1970s, initially in California, vehicles were fitted with catalytic converters to remove the pollutants and so improve the air quality, despite some early resistance from the automotive industry. Slowly the uptake of the catalytic converter has spread around the world. 

More recently the increase in popularity of diesel vehicles, and introduction of legislation to cover a wider range of vehicle types, has led to new problems and further challenges are expected as we look to the future.