A study on the Effects of DOC on the mineral salt components in particulate matter emitted from diesel engine

For revealing the impact of diesel oxidation catalyst (DOC) on the particulate emissions of diesel engine, an experimental study on the number concentration of exhaust particulate and the emission rate of mineral salt components in a diesel engine equipped with DOC is conducted by using ELPI, ICP-AES and IC. The results show that with DOC, the number of exhaust particulates reduces, but the emission rate of most mineral salt components increases, and they increase with the rise in load, in which the increase rate of crustal elements is greater than that of factitious elements. In most working conditions the emission rate of SO₄^2- increases and it increases with the rise in speed and load; and the mass fraction of SO₄^2- in particulate also increases, and it increases with the rise in load.