A Review of the Effect of Petrol Composition on Unregulated Motor Vehicle Emissions with Particular Emphasis on Non-Catalyst Vehicles

Over the period covered by this review many changes have been made to fuel composition. A number of these changes have been made with the intention of improving the environment by altering exhaust emissions. On some occasions it appears that refiners may have removed one hazard only to create another. A typical example is the introduction of oxygenates at the expense of aromatics. Our review shows that this will reduce benzene and aromatic emissions but will increase aldehyde emissions. The use of catalytic converters minimises many of these fuel effects but in many countries the catalytic vehicle population is small and these fuel changes may have significant effects if the fuels are used in cars not fitted with exhaust treatment devices. Concern grows regarding vehicular emissions as the number of vehicles continues to rise. It becomes even more important that we understand the environmental effects that changing fuel compositions will have. Particularly indicted appears to be the increase in the use of...