The Oxidation Rate of Diesel Particulate Which Contains Lead

Discussion: “Heat Transfer With Insulated Combustion Chamber Walls and Its Influence on the Performance of Diesel Engines” (Woschni, G., and Spindler, W., 1988, ASME J. Eng. Gas Turbines Power, 110, pp. 482–488)

“…The wall temperature above which no significant deposits exist is not known precisely. Reported values of the ignition temperature of soot particles [42,43] ranged from 620 to 870 K, although the ignition temperature could be lowered substantially with additives [42,44,45]. Nevertheless these results suggest the possibility that a decrease in the thickness of wall deposits with increasing wall temperature may be the cause of the measured increase in the transient surface heat flux during combustion with increasing wall temperature.…”

Acetylene soot reaction with NO in the presence of CO

“…The surface complexes, C f (O), formed in reaction (15) decompose to produce more reactive sites, C f . These carbon active sites may take part in the carbon-NO reaction, represented by reactions (1)- (5), and therefore increase the NO conversion compared with the case in which only NO was present. The newly formed active sites, sometimes called nascent sites, are reported to be even more reactive to NO than the ones formed in carbon-NO reaction [34].…”

“…In general, the value of NO reduction for a given carbon weight increases slightly as the initial concentration of CO rises. As has been mentioned before, there are two possible processes which can explain the increase in NO reduction by the presence of CO. One process is represented by reaction (6) that leads to the generation of new active carbon sites, C f , that take part in the acetylene soot-NO reaction, as represented by reactions (1)- (5). The other process is represented by reaction (7), although in this case it may not be considered the dominant process due to the absence of mineral impurities in the acetylene soot, which is corroborated by the low CO 2 concentrations obtained (lower than 100 ppmv).…”

“…Once it is formed and before leaving the combustion chamber, soot can interact with the surrounding gaseous atmosphere, especially with O 2 and NO. Several diesel soot oxidation studies can be found [4][5][6][7][8][9] in literature but not many for soot from hydrocarbon pyrolysis. Besides, the reaction between soot and NO can also contribute to reducing the emissions of both pollutants.…”

Aerosol nanoparticles synthesis and their application on monolithic reactors for catalytic soot oxidation and solar hydrogen production from water-splitting

“…However, this exponent exhibits a wide variation among the studies reviewed: most studies at low temperatures report the order of reaction in oxygen to be unity, while Neeft et al [135] found that the order of the reaction was 0.76-0.94 at temperatures around 500 o C and Petersen [185] found that the order was 0.5 at the same temperature. Also, again in [133] it was noted that Neeft and de Soete concluded that a shrinking core model applies in the oxidation of soot.…”