Reducing the emission of particles from a diesel engine by adding an oxygenate to the fuel.

Particulate and high emissions of NO(x) are the main problems that are associated with diesel engines. Therefore, techniques and fuels that promote a reduction in these emissions currently are attracting great interest. In this paper, a mixture of acetal and regular diesel fuel has been tested in a heavy-duty diesel engine. The effect was a marked decrease in particle number and the estimated particle mass. A small reduction of the engine power was also observed; however, the net effect was nevertheless a reduction in the emission of CO2 per European stationary cycle. The emissions of HC, CO, NO(x), some aldehydes, and hydrocarbons were only slightly affected by the new fuel composition. An exception was the emission of acetaldehyde, which was almost quadrupled, probably reflecting the decomposition and oxidation of acetal to acetaldehyde.