Use our handy guide to find out. From walking to work to carpooling, there are lots of ways you can reduce your impact. Discover your commuting style. Since most pollution from cars and trucks is due to the burning of fuel, you can reduce pollution from these sources by burning less fuel, burning fuel cleaner and burning cleaner fuel. The MPCA serves as an advisor and technical resource for a transportation planning in Minnesota to ensure the efforts support air quality improvements.
Transportation planning that reduces air pollution promotes:. For cars of 1. In particular it should be possible to satisfy the standards by simple lean-burn techniques, combined with an oxidation catalyst.
Lean-burn engines have been under development since the s. The diesel engine is a successful example of a true lean-burn engine. It was in recognition of the advantages of diesel engines in terms of fuel economy and lower levels of nitrogen oxide pollution that emissions engineers in the motor industry sought to produce petrol engines that would operate with air:fuel ratios as lean as those possible in a diesel engine. At air:fuel ratios greater than the production of nitrogen oxides is considerably reduced and better fuel economy is obtained.
However, emissions of hydrocarbons increase. There is, however, sufficient excess oxygen in the exhaust gas to enable those hydrocarbons to be removed simply by fitting an oxidation catalyst into the exhaust system. The challenge for the engineer is to maintain combustion and driveability at these lean air: fuel ratios. Heat losses from the engine are minimised by designing the combustion chamber with a minimum surface area: volume ratio.
Also, to ensure good combustion it is necessary to produce a high energy spark. The motor industry now has two alternative technologies to meet the new standards. Undoubtedly some car manufacturers will opt for this proven route, and particularly for cars greater than 2 litres the three-way catalyst using platinum promoted by rhodium will be the preferred choice.
For smaller cars, the choice is between the lean-burn engine, fitted with a palladium-promoted platinum oxidation catalyst and the three-way catalyst with an engine fuel management system controlled to ensure that the exhaust maintains the stoichiometry necessary for efficient operation of the three-way catalyst. Read more from this issue ». Enter your email address to receive our quarterly alerts.
Searles Johnson Matthey Chemicals Limited. West German Initiatives Consideration of exhaust emission standards for motor cars that could use platinum metal catalysts for their control started in Europe as long ago as July Harrison,, B. Cooper and A. Wilkins, Platinum Metals Rev. Diwell and B. Please click here to see any active alerts.
When shopping for a new car, look for fuel efficient vehicles with low greenhouse gas emissions. These cars can help the environment while potentially saving you money on fuel costs at the pump. Follow these tips:. Use the EPA's Fuel Economy and Environment Label to compare different vehicle models and find the most fuel efficient and environmentally friendly vehicle that meets your needs.
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