Gasoline automobile catalysis and its historical journey to cleaner air

Environmental regulations in effect since the seventies have been instrumental in promoting continuous progress in the treatment of automotive exhausts, leading to an effective reduction in the emissions of carbon monoxide, unburned non-methane hydrocarbons, oxides of nitrogen and total particulates matter. This review provides an abbreviated history of the technological advances in the area of automotive catalysis achieved over almost 40 years, primarily by catalyst companies in concert with automobile manufacturers throughout the world. While technological milestones are discussed, the importance of fuel economy in decreasing CO2 emissions is acknowledged, alongside the need of decreasing the use of precious metals and improving the overall electronic control of the exhaust system. The transportation industry is facing the growing desire for a quantum jump towards non-fossil fuel vehicles. Therefore, recent developments in the area of batteries and fuel cell vehicles will also be introduced. Catalysis has been crucial for the transportation sector, as it has enabled the treatment of automotive exhausts over the years in agreement with evolving environmental regulations. This review details the most important milestones in automotive catalysis, while looking at the future of the field.