Aldehyde, Ketone and Methane Emissions from Motor Vehicle Exhaust: A Critical Review

Abstract

Recent data indicate that, in many countries, mobile sources are responsible for the largest portion of emissions of aldehydes, ketones and certain other air toxic pollutants. These air toxic pollutants along with methane are either carcinogenic or pose significant human health threat. These pollutants also add to global warming in a substantial way. This paper gives an overview of their properties, basic chemistry and conditions of formation in internal combustion engines. Again worldwide many countries are promoting alternative fuels to tackle the crisis of traditional fuel. But the impact of this movement toward alternative fuels with respect to toxic emissions has not been well studied. Therefore, in this paper the analysis on the effects of engine operation and fuelling parameters is also reviewed with specific references in gasoline, diesel, natural gas, liquefied petroleum gas, ethanol blended petrol and Biodiesel fuelled engines. This is accompanied by the review of the studies of the performance of exhaust catalytic converters with respect to aldehydes, ketones and methane. Additionally, aldehydes, ketones and methane detection and measurement methods are summarized and analyzed from the view of their applicability to exhaust gas analysis.

Emission analysis of a Diesel Engine Operating in Diesel–Ethanol Dual-Fuel mode

“…This can be disregarded in this work since the 580 fuels do not contain nitrogen species in their composition. Table 1 [17,19,25,26,28,35,37,39]. Q7 800…”

Experimental investigations on direct injection diesel engine with ceramic coated combustion chamber with carbureted alcohols and crude jatropha oil

“…Aldehyde vapors effects on human health include irritation of eye, throat, nose, asthma, pulmonary function. Thresholds for sensory irritation determined by controlled exposure studies, are reported as 0.6-1.2 mg/m 3 [0.5-1.0 ppm] (formaldehyde) and 90 mg/m 3 [50 ppm] (acetaldehyde) [53]. These levels are substantially higher than the generally reported ambient air concentrations of these vapors.…”

“…These aldehydes are carcinogenic in nature and once they are inhaled, cause severe headache and vomiting sensation [53]. Aldehyde vapors effects on human health include irritation of eye, throat, nose, asthma, pulmonary function.…”

Emission analysis of a modern Tier 4 DI diesel engine fueled by biodiesel-diesel blends with a cold flow improver (Wintron Synergy) at multiple idling conditions

“…Due to higher viscosity of biodiesel and Wintron Synergy, poor spray characteristics may lead to longer ignition delay causing higher NO x emissions. Although the share of NO 2 in total NO x in spark-ignition engines is negligibly small, it could be as high as 10-30% in diesel engines [38]. NO formed in the flame zone can be rapidly converted to NO 2 with reactions such as;…”