抄録
Emission standards for diesel engines have been tightened all over the world since diesel engine exhaust emissions contribute significantly to urban and global pollution. The use of fuel additive has been proposed as a cost-effective strategy for reducing pollutant emissions from diesel-powered engines. This paper introduces a possible mechanism of the catalytic reactions in the combination of platinum and cerium in diesel engine, and also shows an example of the actual use of a platinum-cerium bimetallic fuel additive for a diesel engine. Possible mechanism is suggested as follows; the soot oxidation occurs on Pt utilizing oxygen, and also occurs on Ce consuming nitrogen dioxide. A previous study showed that 54% of elemental carbon, 23% of organic carbon, and 34% of PM2.5 were reduced when 0.13 ppm Pt and 7.5ppm Ce of the additive were used. The investigation of long-term effect for the diesel emission characteristics associated with the use of the fuel additive and other pollution control technologies is needed for further study.